Red Hat Enterprise Linux 5 Security Technical Implementation Guide

Version

GEN000020

Vuln IDs

V-756

Rule IDs

SV-37350r2_rule

If the system does not require valid root authentication before it boots into single-user or maintenance mode, anyone who invokes single-user or maintenance mode is granted privileged access to all files on the system.System Administrator

Checks: C-36041r1_chk

Check if the system requires a password for entering single-user mode. # grep ':S:' /etc/inittab If /sbin/sulogin is not listed, this is a finding.

Fix: F-31285r2_fix

Edit /etc/inittab and set sulogin to run in single-user mode. Example line in /etc/inittab: ~:S:wait:/sbin/sulogin Note: The first field in the /etc/inittab line may be any sequence of 1-4 characters.

b

Direct logins must not be permitted to shared, default, application, or utility accounts.

IA-2 - Medium - CCI-000770 - V-760 - SV-37419r2_rule

RMF Control

IA-2

Severity

M

CCI

Version

GEN000280

Vuln IDs

V-760

Rule IDs

SV-37419r2_rule

Shared accounts (accounts where two or more people log in with the same user identification) do not provide identification and authentication. There is no way to provide for non-repudiation or individual accountability.trueSystem AdministratorInformation Assurance Officer

Checks: C-36102r2_chk

Use the last command to check for multiple accesses to an account from different workstations/IP addresses. # last -w If users log directly onto accounts, rather than using the switch user (su) command from their own named account to access them, this is a finding (such as logging directly on to oracle). Verify with the SA or the IAO on documentation for users/administrators to log into their own accounts first and then switch user (su) to the account to be shared has been maintained including requirements and procedures. If no such documentation exists, this is a finding.

Fix: F-31348r2_fix

Use the switch user (su) command from a named account login to access shared accounts. Document requirements and procedures for users/administrators to log into their own accounts first and then switch user (su) to the account to be shared.

b

All accounts on the system must have unique user or account names.

IA-2 - Medium - CCI-000764 - V-761 - SV-27063r1_rule

RMF Control

IA-2

Severity

M

CCI

CCI-000764

Version

GEN000300

Vuln IDs

V-761

Rule IDs

SV-27063r1_rule

A unique user name is the first part of the identification and authentication process. If user names are not unique, there can be no accountability on the system for auditing purposes. Multiple accounts sharing the same name could result in the denial of service to one or both of the accounts or unauthorized access to files or privileges.System AdministratorIAIA-1, IAIA-2

Checks: C-36103r1_chk

Check the system for duplicate account names. Example: # pwck -r If any duplicate account names are found, this is a finding.

Fix: F-31349r1_fix

Change user account names, or delete accounts, so each account has a unique name.

b

All accounts must be assigned unique User Identification Numbers (UIDs).

IA-2 - Medium - CCI-000764 - V-762 - SV-27068r1_rule

RMF Control

IA-2

Severity

M

CCI

CCI-000764

Version

GEN000320

Vuln IDs

V-762

Rule IDs

SV-27068r1_rule

Accounts sharing a UID have full access to each others' files. This has the same effect as sharing a login. There is no way to assure identification, authentication, and accountability because the system sees them as the same user. If the duplicate UID is 0, this gives potential intruders another privileged account to attack.System AdministratorIAIA-1, IAIA-2

Checks: C-36104r2_chk

Perform the following to ensure there are no duplicate UIDs: # cut -d: -f3 /etc/passwd | uniq -d If any duplicate UIDs are found, this is a finding.

Fix: F-31350r1_fix

Edit user accounts to provide unique UIDs for each account.

b

The Department of Defense (DoD) login banner must be displayed immediately prior to, or as part of, console login prompts.

AC-8 - Medium - CCI-000048 - V-763 - SV-37169r1_rule

RMF Control

AC-8

Severity

M

CCI

Version

GEN000400

Vuln IDs

V-763

Rule IDs

SV-37169r1_rule

Failure to display the logon banner prior to a logon attempt will negate legal proceedings resulting from unauthorized access to system resources.System AdministratorECWM-1

Checks: C-35874r1_chk

Access the system console and make a login attempt. Check for either of the following login banners based on the character limitations imposed by the system. An exact match is required. If one of these banners is not displayed, this is a finding. You are accessing a U.S. Government (USG) Information System (IS) that is provided for USG-authorized use only. By using this IS (which includes any device attached to this IS), you consent to the following conditions: -The USG routinely intercepts and monitors communications on this IS for purposes including, but not limited to, penetration testing, COMSEC monitoring, network operations and defense, personnel misconduct (PM), law enforcement (LE), and counterintelligence (CI) investigations. -At any time, the USG may inspect and seize data stored on this IS. -Communications using, or data stored on, this IS are not private, are subject to routine monitoring, interception, and search, and may be disclosed or used for any USG-authorized purpose. -This IS includes security measures (e.g., authentication and access controls) to protect USG interests- -not for your personal benefit or privacy. -Notwithstanding the above, using this IS does not constitute consent to PM, LE or CI investigative searching or monitoring of the content of privileged communications, or work product, related to personal representation or services by attorneys, psychotherapists, or clergy, and their assistants. Such communications and work product are private and confidential. See User Agreement for details. OR I've read & consent to terms in IS user agreem't.

Fix: F-31128r1_fix

Edit /etc/issue and add one of the DoD login banners (based on the character limitations imposed by the system). DoD Login Banners: You are accessing a U.S. Government (USG) Information System (IS) that is provided for USG-authorized use only. By using this IS (which includes any device attached to this IS), you consent to the following conditions: -The USG routinely intercepts and monitors communications on this IS for purposes including, but not limited to, penetration testing, COMSEC monitoring, network operations and defense, personnel misconduct (PM), law enforcement (LE), and counterintelligence (CI) investigations. -At any time, the USG may inspect and seize data stored on this IS. -Communications using, or data stored on, this IS are not private, are subject to routine monitoring, interception, and search, and may be disclosed or used for any USG-authorized purpose. -This IS includes security measures (e.g., authentication and access controls) to protect USG interests- -not for your personal benefit or privacy. -Notwithstanding the above, using this IS does not constitute consent to PM, LE or CI investigative searching or monitoring of the content of privileged communications, or work product, related to personal representation or services by attorneys, psychotherapists, or clergy, and their assistants. Such communications and work product are private and confidential. See User Agreement for details. OR I've read & consent to terms in IS user agreem't.

b

Successful and unsuccessful logins and logouts must be logged.

AU-2 - Medium - CCI-000126 - V-765 - SV-37178r1_rule

RMF Control

AU-2

Severity

M

CCI

Version

GEN000440

Vuln IDs

V-765

Rule IDs

SV-37178r1_rule

Monitoring and recording successful and unsuccessful logins assists in tracking unauthorized access to the system. Without this logging, the ability to track unauthorized activity to specific user accounts may be diminished.System AdministratorECAR-1, ECAR-2, ECAR-3

Checks: C-35882r1_chk

Determine if all logon attempts are being logged. Procedure: Verify successful logins are being logged: # last -R | more If the command does not return successful logins, this is a finding. Verify if unsuccessful logons are being logged: # lastb -R | more If the command does not return unsuccessful logins, this is a finding.

Fix: F-31137r1_fix

Make sure the collection files exist. Procedure: If there are no successful logins being returned from the "last" command, create /var/log/wtmp: # touch /var/log/wtmp If there are no unsuccessful logins being returned from the "lastb" command, create /var/log/btmp: # touch /var/log/btmp

b

The system must disable accounts after three consecutive unsuccessful login attempts.

AC-7 - Medium - CCI-000044 - V-766 - SV-37203r1_rule

RMF Control

AC-7

Severity

M

CCI

CCI-000044

Version

GEN000460

Vuln IDs

V-766

Rule IDs

SV-37203r1_rule

Disabling accounts after a limited number of unsuccessful login attempts improves protection against password guessing attacks.System AdministratorECLO-1, ECLO-2

Checks: C-35895r1_chk

Check the pam_tally configuration. # more /etc/pam.d/system-auth Confirm the following line is configured, before any "auth sufficient" lines: auth required pam_tally2.so deny=3 If no such line is found, this is a finding.

Fix: F-31153r1_fix

By default link /etc/pam.d/system-auth points to /etc/pam.d/system-auth-ac which is the file maintained by the authconfig utility. In order to add pam options other than those available via the utility create /etc/pam.d/system-auth-local with the options and including system-auth-ac. In order to set the account lockout to three failed attempts the content should be similar to: auth required pam_access.so auth required pam_tally2.so deny=3 auth include system-auth-ac account required pam_tally2.so account include system-auth-ac password include system-auth-ac session include system-auth-ac Once system-auth-local is written reset the /etc/pam.d/system-auth to point to system-auth-local. This is necessary because authconfig writes directly to system-auth-ac so any changes made by hand will be lost if authconfig is run.

b

The delay between login prompts following a failed login attempt must be at least 4 seconds.

AC-7 - Medium - CCI-002238 - V-768 - SV-37213r2_rule

RMF Control

AC-7

Severity

M

CCI

CCI-002238

Version

GEN000480

Vuln IDs

V-768

Rule IDs

SV-37213r2_rule

Enforcing a delay between successive failed login attempts increases protection against automated password guessing attacks.System Administrator

Checks: C-35903r2_chk

Check the value of the FAIL_DELAY variable and the ability to use it. Procedure: # grep FAIL_DELAY /etc/login.defs If the value does not exist, or is less than 4, this is a finding. Check for the use of pam_faildelay. # grep pam_faildelay /etc/pam.d/system-auth* If pam_faildelay.so module is not present, this is a finding. If pam_faildelay is present only in /etc/pam.d/system-auth-ac: ensure that /etc/pam.d/system-auth includes /etc/pam.d/system-auth-ac. #grep system-auth-ac /etc/pam.d/system-auth This should return: auth include system-auth-ac account include system-auth-ac password include system-auth-ac session include system-auth-ac /etc/pam.d/system-auth-ac should only be included by /etc/pam.d/system-auth. All other pam files should include /etc/pam.d/system-auth. If pam_faildelay is not defined in /etc/pam.d/system-auth either directly or through inclusion of system-auth-ac, this is a finding.

Fix: F-31161r1_fix

Add the pam_faildelay module and set the FAIL_DELAY variable. Procedure: Edit /etc/login.defs and set the value of the FAIL_DELAY variable to 4 or more. The default link /etc/pam.d/system-auth points to /etc/pam.d/system-auth-ac which is the file maintained by the authconfig utility. In order to add pam options other than those available via the utility create or modify /etc/pam.d/system-auth-local with the options and including system-auth-ac. For example: auth required pam_access.so auth optional pam_faildelay.so delay=4000000 auth include system-auth-ac account include system-auth-ac password include system-auth-ac session include system-auth-ac Once system-auth-local is written ensure the /etc/pam.d/system-auth points to system-auth-local. This is necessary because authconfig writes directly to system-auth-ac so any manual changes made will be lost if authconfig is run.

b

The root user must not own the logon session for an application requiring a continuous display.

AC-6 - Medium - CCI-000225 - V-769 - SV-37232r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN000520

Vuln IDs

V-769

Rule IDs

SV-37232r1_rule

If an application is providing a continuous display and is running with root privileges, unauthorized users could interrupt the process and gain root access to the system.System AdministratorPESL-1

Checks: C-35914r1_chk

If there is an application running on the system continuously in use (such as a network monitoring application), ask the SA what the name of the application is. Verify documentation exists for the requirement and justification of the application. If no documentation exists, this is a finding. Execute "ps -ef | more" to determine which user owns the process(es) associated with the application. If the owner is root, this is a finding.

Fix: F-31178r1_fix

Configure the system so the owner of a session requires a continuous screen display, such as a network management display, is not root. Ensure the display is also located in a secure, controlled access area. Document and justify this requirement and ensure the terminal and keyboard for the display (or workstation) are secure from all but authorized personnel by maintaining them in a secure area, in a locked cabinet where a swipe card, or other positive forms of identification, must be used to gain entry.

c

The system must not have accounts configured with blank or null passwords.

CM-6 - High - CCI-000366 - V-770 - SV-37259r1_rule

RMF Control

CM-6

Severity

H

CCI

Version

GEN000560

Vuln IDs

V-770

Rule IDs

SV-37259r1_rule

If an account is configured for password authentication but does not have an assigned password, it may be possible to log into the account without authentication. If the root user is configured without a password, the entire system may be compromised. For user accounts not using password authentication, the account must be configured with a password lock value instead of a blank or null value. System AdministratorIAIA-1, IAIA-2

Checks: C-35949r1_chk

Verify the system will not log in accounts with blank passwords. # grep nullok /etc/pam.d/system-auth /etc/pam.d/system-auth-ac If an entry for nullok is found, this is a finding on Linux.

Fix: F-31205r1_fix

Edit /etc/pam.d/system-auth and remove the "nullok" setting.

b

The root account must be the only account having a UID of 0.

CM-6 - Medium - CCI-000366 - V-773 - SV-37347r2_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN000880

Vuln IDs

V-773

Rule IDs

SV-37347r2_rule

If an account has a UID of 0, it has root authority. Multiple accounts with a UID of 0 afford more opportunity for potential intruders to guess a password for a privileged account. System Administrator

Checks: C-36039r2_chk

Check the system for duplicate UID 0 assignments by listing all accounts assigned UID 0. Procedure: # awk -F: '($3 == 0) { print $1 }' /etc/passwd If any accounts other than root are assigned UID 0, this is a finding.

Fix: F-31283r1_fix

Remove or change the UID of accounts other than root that have UID 0.

a

The root user's home directory must not be the root directory (/).

CM-6 - Low - CCI-000366 - V-774 - SV-37349r2_rule

RMF Control

CM-6

Severity

L

CCI

Version

GEN000900

Vuln IDs

V-774

Rule IDs

SV-37349r2_rule

Changing the root home directory to something other than / and assigning it a 0700 protection makes it more difficult for intruders to manipulate the system by reading the files root places in its default directory. It also gives root the same discretionary access control for root's home directory as for the other user home directories.System Administrator

Checks: C-36040r2_chk

Determine if root is assigned a home directory other than / by listing its home directory. Procedure: # awk -F: '($1 == "root") { print $6 }' /etc/passwd If the root user home directory is /, this is a finding.

Fix: F-31284r1_fix

The root home directory should be something other than / (such as /roothome). Procedure: # mkdir /rootdir # chown root /rootdir # chgrp root /rootdir # chmod 700 /rootdir # cp -r /.??* /rootdir/. Then, edit the passwd file and change the root home directory to /rootdir. The cp -r /.??* command copies all files and subdirectories of file names beginning with "." into the new root directory, which preserves the previous root environment. Ensure you are in the "/" directory when executing the "cp" command.

b

The root account's home directory (other than /) must have mode 0700.

AC-6 - Medium - CCI-000225 - V-775 - SV-37355r2_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN000920

Vuln IDs

V-775

Rule IDs

SV-37355r2_rule

Permissions greater than 0700 could allow unauthorized users access to the root home directory.System Administrator

Checks: C-36044r2_chk

Check the mode of the root home directory. Procedure: # find ~root -type d -prune -exec ls -ld {} \; If the mode of the directory is not equal to 0700, this is a finding. If the home directory is /, this check will be marked "Not Applicable".

Fix: F-31288r1_fix

The root home directory will have permissions of 0700. Do not change the protections of the / directory. Use the following command to change protections for the root home directory: # chmod 0700 /rootdir.

b

The root account's executable search path must be the vendor default and must contain only absolute paths.

CM-6 - Medium - CCI-000366 - V-776 - SV-37360r3_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN000940

Vuln IDs

V-776

Rule IDs

SV-37360r3_rule

The executable search path (typically the PATH environment variable) contains a list of directories for the shell to search to find executables. If this path includes the current working directory or other relative paths, executables in these directories may be executed instead of system commands. This variable is formatted as a colon-separated list of directories. If there is an empty entry, such as a leading or trailing colon or two consecutive colons, this is interpreted as the current working directory. Entries starting with a slash (/) are absolute paths.System Administrator

Checks: C-36049r4_chk

To view the root user's PATH, log in as the root user, and execute: # env | grep PATH This variable is formatted as a colon-separated list of directories. If there is an empty entry, such as a leading or trailing colon, or two consecutive colons, this is a finding. If an entry begins with a character other than a slash (/) or other than "$PATH", it is a relative path and this is a finding. If directories beyond those in the vendor's default root path or locally approved additional directories are present, this is a finding.

Fix: F-31293r3_fix

Edit the root user's local initialization files ~/.profile,~/.bashrc (assuming root shell is bash). Change any found PATH variable settings to the vendor's default path for the root user. Remove any empty path entries or references to relative paths.

b

The root account must not have world-writable directories in its executable search path.

CM-6 - Medium - CCI-000366 - V-777 - SV-37372r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN000960

Vuln IDs

V-777

Rule IDs

SV-37372r1_rule

If the root search path contains a world-writable directory, malicious software could be placed in the path by intruders and/or malicious users and inadvertently run by root with all of root's privileges. System AdministratorECCD-1, ECCD-2

Checks: C-36059r1_chk

Check for world-writable permissions on all directories in the root user's executable search path. Procedure: # ls -ld `echo $PATH | sed "s/:/ /g"` If any of the directories in the PATH variable are world-writable, this is a finding.

Fix: F-31304r1_fix

For each world-writable path in root's executable search path, do one of the following: 1. Remove the world-writable permission on the directory. Procedure: # chmod o-w <path> 2. Remove the world-writable directory from the executable search path. Procedure: Identify and edit the initialization file referencing the world-writable directory and remove it from the PATH variable.

b

The system must prevent the root account from directly logging in except from the system console.

IA-2 - Medium - CCI-000770 - V-778 - SV-37374r1_rule

RMF Control

IA-2

Severity

M

CCI

Version

GEN000980

Vuln IDs

V-778

Rule IDs

SV-37374r1_rule

Limiting the root account direct logins to only system consoles protects the root account from direct unauthorized access from a non-console device.System Administrator

Checks: C-36060r1_chk

Check /etc/securetty # more /etc/securetty If the file does not exist, or contains more than "console" or a single "tty" device this is a finding.

Fix: F-31305r1_fix

Create if needed and set the contents of /etc/securetty to a "console" or "tty" device. # echo console > /etc/securetty or # echo tty1 > /etc/securetty

b

GIDs reserved for system accounts must not be assigned to non-system groups.

CM-6 - Medium - CCI-000366 - V-780 - SV-37157r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN000360

Vuln IDs

V-780

Rule IDs

SV-37157r1_rule

Reserved GIDs are typically used by system software packages. If non-system groups have GIDs in this range, they may conflict with system software, possibly leading to the group having permissions to modify system files.System AdministratorECSC-1

Checks: C-35866r1_chk

Confirm all accounts with a GID of 499 and below are used by a system account. Procedure: List all the users with a GID of 0-499. # cut -d: -f 1,4 /etc/passwd|egrep ":[1-4][0-9]{2}$|:[0-9]{1,2}$" If a GID reserved for system accounts (0 - 499) is used by a non-system account, this is a finding.

Fix: F-31121r1_fix

Change the primary group GID numbers for non-system accounts with reserved primary group GIDs (those less or equal to 499).

a

All GIDs referenced in the /etc/passwd file must be defined in the /etc/group file.

CM-6 - Low - CCI-000366 - V-781 - SV-27072r1_rule

RMF Control

CM-6

Severity

L

CCI

Version

GEN000380

Vuln IDs

V-781

Rule IDs

SV-27072r1_rule

If a user is assigned the GID of a group not existing on the system, and a group with the GID is subsequently created, the user may have unintended rights to the group. System AdministratorECSC-1

Checks: C-27989r1_chk

Perform the following to ensure there are no GIDs referenced in /etc/passwd not defined in /etc/group: # pwck -r If GIDs referenced in /etc/passwd are not defined in /etc/group are returned, this is a finding.

Fix: F-935r3_fix

Add a group to the system for each GID referenced without a corresponding group.

b

The system must have a host-based intrusion detection tool installed.

SI-4 - Medium - CCI-001259 - V-782 - SV-37746r2_rule

RMF Control

SI-4

Severity

M

CCI

CCI-001259

Version

GEN006480

Vuln IDs

V-782

Rule IDs

SV-37746r2_rule

Without a host-based intrusion detection tool, there is no system-level defense when an intruder gains access to a system or network. Additionally, a host-based intrusion detection tool can provide methods to immediately lock out detected intrusion attempts.System Administrator

Checks: C-36942r2_chk

Ask the SA or IAO if a host-based intrusion detection application is loaded on the system. The preferred intrusion detection system is McAfee HBSS available through Cybercom. If another host-based intrusion detection application, such as SELinux, is used on the system, this is not a finding. Procedure: Examine the system to see if the Host Intrusion Prevention System (HIPS) is installed #rpm -qa | grep MFEhiplsm If the MFEhiplsm package is installed, HBSS is being used on the system. If another host-based intrusion detection system is loaded on the system # find / -name <daemon name> Where <daemon name> is the name of the primary application daemon to determine if the application is loaded on the system. Determine if the application is active on the system. Procedure: # ps -ef | grep <daemon name> If no host-based intrusion detection system is installed on the system, this is a finding.

Fix: F-32207r1_fix

Install a host-based intrusion detection tool.

b

System security patches and updates must be installed and up-to-date.

SI-2 - Medium - CCI-001227 - V-783 - SV-27059r2_rule

RMF Control

SI-2

Severity

M

CCI

CCI-001227

Version

GEN000120

Vuln IDs

V-783

Rule IDs

SV-27059r2_rule

Timely patching is critical for maintaining the operational availability, confidentiality, and integrity of information technology (IT) systems. However, failure to keep operating system and application software patched is a common mistake made by IT professionals. New patches are released daily, and it is often difficult for even experienced system administrators to keep abreast of all the new patches. When new weaknesses in an operating system exist, patches are usually made available by the vendor to resolve the problems. If the most recent security patches and updates are not installed, unauthorized users may take advantage of weaknesses present in the unpatched software. The lack of prompt attention to patching could result in a system compromise.System Administrator

Checks: C-27973r3_chk

Obtain the list of available package security updates from Red Hat. Check the available package security updates have been installed on the system. Use the "rpm" command to list the packages installed on the system. Example: # rpm -qa -last If updated packages are available and applicable to the system and have not been installed, this is a finding. One source for the list of Red Hat updates is available at https://access.redhat.com/security/updates/active/

Fix: F-31302r1_fix

Install the patches or updated packages available from the vendor.

b

System files and directories must not have uneven access permissions.

AC-6 - Medium - CCI-000225 - V-784 - SV-37159r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001140

Vuln IDs

V-784

Rule IDs

SV-37159r1_rule

Discretionary access control is undermined if users, other than a file owner, have greater access permissions to system files and directories than the owner.System AdministratorECCD-1, ECCD-2

Checks: C-35867r1_chk

Check system directories for uneven file permissions. Procedure: # ls -lL /etc /bin /usr/bin /usr/lbin /usr/usb /sbin /usr/sbin Uneven file permissions exist if the file owner has less permissions than the group or other user classes. If any of the files in the above listed directories contain uneven file permissions, this is a finding.

Fix: F-31122r1_fix

Change the mode of files with uneven permissions so owners do not have less permission than group or world users.

b

All files and directories must have a valid owner.

CM-6 - Medium - CCI-000366 - V-785 - SV-37161r2_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN001160

Vuln IDs

V-785

Rule IDs

SV-37161r2_rule

Un-owned files and directories may be unintentionally inherited if a user is assigned the same UID as the UID of the un-owned files.System Administrator

Checks: C-35868r2_chk

Check the system for files with no assigned owner. Procedure: # find / -ignore_readdir_race -nouser If any files have no assigned owner, this is a finding. Caution should be used when centralized authorization is used because valid files may appear as unowned due to communication issues.

Fix: F-31123r1_fix

All directories and files (executable and data) will have an identifiable owner and group name. Either trace files to an authorized user, change the file's owner to root, or delete them. Determine the legitimate owner of the files and use the chown command to set the owner and group to the correct value. If the legitimate owner cannot be determined, change the owner to root (but make sure none of the changed files remain executable because they could be Trojan horses or other malicious code). Examine the files to determine their origin and the reason for their lack of an owner/group.

b

All network services daemon files must have mode 0755 or less permissive.

AC-6 - Medium - CCI-000225 - V-786 - SV-37194r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001180

Vuln IDs

V-786

Rule IDs

SV-37194r1_rule

Restricting permission on daemons will protect them from unauthorized modification and possible system compromise.System AdministratorECLP-1

Checks: C-35891r1_chk

Check the mode of network services daemons. # find /usr/sbin -type f -perm +022 -exec stat -c %a:%n {} \; This will return the octal permissions and name of all files that are group or world writable. If any network services daemon listed is world or group writable (either or both of the 2 lowest order digits contain a 2, 3 or 6), this is a finding. Note: Network daemons not residing in these directories (such as httpd or sshd) must also be checked for the correct permissions.

Fix: F-31146r1_fix

Change the mode of the network services daemon. # chmod go-w <path>

b

System log files must have mode 0640 or less permissive.

SI-11 - Medium - CCI-001314 - V-787 - SV-37228r3_rule

RMF Control

SI-11

Severity

M

CCI

CCI-001314

Version

GEN001260

Vuln IDs

V-787

Rule IDs

SV-37228r3_rule

If the system log files are not protected, unauthorized users could change the logged data, eliminating its forensic value.System Administrator

Checks: C-35918r4_chk

Check the mode of log files. Procedure: # find /var/log /var/log/syslog /var/adm -type f -perm -640 \! -perm 640 With the exception of /var/log/wtmp, /var/log/Xorg.0.log, and /var/log/gdm/:0.log, if any of the log files have modes more permissive than 0640, this is a finding.

Fix: F-31175r1_fix

Change the mode of the system log file(s) to 0640 or less permissive. Procedure: # chmod 0640 /path/to/system-log-file Note: Do not confuse system log files with audit logs.

b

All skeleton files (typically those in /etc/skel) must have mode 0644 or less permissive.

AC-6 - Medium - CCI-000225 - V-788 - SV-37292r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001800

Vuln IDs

V-788

Rule IDs

SV-37292r1_rule

If the skeleton files are not protected, unauthorized personnel could change user startup parameters and possibly jeopardize user files. System AdministratorECLP-1

Checks: C-35988r1_chk

Check skeleton files permissions. # ls -alL /etc/skel If a skeleton file has a mode more permissive than 0644, this is a finding.

Fix: F-31240r1_fix

Change the mode of skeleton files with incorrect mode: # chmod 0644 <skeleton file>

b

NIS/NIS+/yp files must be owned by root, sys, or bin.

AC-6 - Medium - CCI-000225 - V-789 - SV-37267r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001320

Vuln IDs

V-789

Rule IDs

SV-37267r1_rule

NIS/NIS+/yp files are part of the system's identification and authentication processes and are critical to system security. Failure to give ownership of sensitive files or utilities to root or bin provides the designated owner and unauthorized users with the potential to access sensitive information or change the system configuration which could weaken the system's security posture.System AdministratorECLP-1

Checks: C-35953r1_chk

Perform the following to check NIS file ownership: # ls -la /var/yp/*; If the file ownership is not root, sys, or bin, this is a finding.

Fix: F-31213r1_fix

Change the ownership of NIS/NIS+/yp files to root, sys or bin. Procedure (example): # chown root <filename>

b

NIS/NIS+/yp files must be group-owned by root, sys, or bin.

AC-6 - Medium - CCI-000225 - V-790 - SV-41577r2_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001340

Vuln IDs

V-790

Rule IDs

SV-41577r2_rule

NIS/NIS+/yp files are part of the system's identification and authentication processes and are, therefore, critical to system security. Failure to give ownership of sensitive files or utilities to root or bin provides the designated owner and unauthorized users with the potential to access sensitive information or change the system configuration which could weaken the system's security posture.System Administrator

Checks: C-40079r2_chk

Perform the following to check NIS file group ownership: # ls -la /var/yp/* If the file group ownership is not root, sys, or bin, this is a finding.

Fix: F-35235r4_fix

Perform the following to change NIS file ownership. # chgrp root /var/yp/*

b

The NIS/NIS+/yp command files must have mode 0755 or less permissive.

AC-6 - Medium - CCI-000225 - V-791 - SV-37272r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001360

Vuln IDs

V-791

Rule IDs

SV-37272r1_rule

NIS/NIS+/yp files are part of the system's identification and authentication processes and are critical to system security. Unauthorized modification of these files could compromise these processes and the system.System AdministratorECLP-1

Checks: C-35964r3_chk

Perform the following to check NIS file permissions. # ls -la /var/yp/* If the file's mode is more permissive than 0755, this is a finding.

Fix: F-31220r1_fix

Change the mode of NIS/NIS+/yp command files to 0755 or less permissive. Procedure (example): # chmod 0755 <filename>

a

Manual page files must have mode 0644 or less permissive.

AC-6 - Low - CCI-000225 - V-792 - SV-37234r3_rule

RMF Control

AC-6

Severity

L

CCI

Version

GEN001280

Vuln IDs

V-792

Rule IDs

SV-37234r3_rule

If manual pages are compromised, misleading information could be inserted, causing actions to compromise the system.System Administrator

Checks: C-35923r3_chk

Check the mode of the manual page files. Procedure: # find /usr/share/man /usr/share/info /usr/share/infopage -type f -perm +022 -exec stat -c %a:%n {} \; |> more Note: This list only displays manual files with offending permissions. If any of the manual page files have a mode more permissive than 0644, this is a finding.

Fix: F-31181r2_fix

Change the mode of manual page files to 0644 or less permissive. Procedure (example): # chmod 0644 /path/to/manpage

b

Library files must have mode 0755 or less permissive.

CM-5 - Medium - CCI-001499 - V-793 - SV-37241r2_rule

RMF Control

CM-5

Severity

M

CCI

Version

GEN001300

Vuln IDs

V-793

Rule IDs

SV-37241r2_rule

Unauthorized access could destroy the integrity of the library files.System Administrator

Checks: C-35933r2_chk

Check the mode of library files. Procedure: # DIRS="/usr/lib /lib /usr/lib64 /lib64";for DIR in $DIRS;do find $DIR -type f -perm +022 -exec stat -c %a:%n {} \;;done This will return the octal permissions and name of all group or world writable files. If any file listed is world or group writable (either or both of the 2 lowest order digits contain a 2, 3 or 6), this is a finding.

Fix: F-31188r1_fix

Change the mode of library files to 0755 or less permissive. Procedure (example): # chmod go-w </path/to/library-file> Note: Library files should have an extension of ".a" or a ".so" extension, possibly followed by a version number.

b

All system command files must have mode 0755 or less permissive.

CM-5 - Medium - CCI-001499 - V-794 - SV-37205r2_rule

RMF Control

CM-5

Severity

M

CCI

Version

GEN001200

Vuln IDs

V-794

Rule IDs

SV-37205r2_rule

Restricting permissions will protect system command files from unauthorized modification. System command files include files present in directories used by the operating system for storing default system executables and files present in directories included in the system's default executable search paths.Elevate to Severity Code I if any file listed world-writable.System AdministratorECLP-1

Checks: C-35897r2_chk

Check the permissions for files in /etc, /bin, /usr/bin, /usr/lbin, /usr/usb, /sbin, and /usr/sbin. Procedure: # DIRS="/etc /bin /usr/bin /usr/lbin /usr/usb /sbin /usr/sbin";for DIR in $DIRS;do find $DIR -type f -perm +022 -exec stat -c %a:%n {} \;;done This will return the octal permissions and name of all group or world writable files. If any command file is listed and is world or group writable (either or both of the 2 lowest order digits contain a 2, 3 or 6), this is a finding. Note: Elevate to Severity Code I if any command file listed is world-writable.

Fix: F-31155r1_fix

Change the mode for system command files to 0755 or less permissive taking into account necessary GIUD and SUID bits. Procedure: # chmod go-w <filename>

b

All system files, programs, and directories must be owned by a system account.

CM-5 - Medium - CCI-001499 - V-795 - SV-37216r1_rule

RMF Control

CM-5

Severity

M

CCI

Version

GEN001220

Vuln IDs

V-795

Rule IDs

SV-37216r1_rule

Restricting permissions will protect the files from unauthorized modification.System AdministratorECLP-1

Checks: C-35906r1_chk

Check the ownership of system files, programs, and directories. Procedure: # ls -lLa /etc /bin /usr/bin /usr/lbin /usr/usb /sbin /usr/sbin If any of the system files, programs, or directories are not owned by a system account, this is a finding.

Fix: F-31164r1_fix

Change the owner of system files, programs, and directories to a system account. Procedure: # chown root /some/system/file (A different system user may be used in place of root.)

b

System files, programs, and directories must be group-owned by a system group.

CM-5 - Medium - CCI-001499 - V-796 - SV-37220r1_rule

RMF Control

CM-5

Severity

M

CCI

Version

GEN001240

Vuln IDs

V-796

Rule IDs

SV-37220r1_rule

Restricting permissions will protect the files from unauthorized modification.System AdministratorECLP-1

Checks: C-35909r1_chk

Check the group-ownership of system files, programs, and directories. Procedure: # ls -lLa /etc /bin /usr/bin /usr/lbin /usr/usb /sbin /usr/sbin If any system file, program, or directory is not owned by a system group, this is a finding.

Fix: F-31167r1_fix

Change the group-owner of system files to a system group. Procedure: # chgrp root /path/to/system/file (System groups other than root may be used.)

b

The /etc/shadow (or equivalent) file must be owned by root.

AC-6 - Medium - CCI-000225 - V-797 - SV-37361r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001400

Vuln IDs

V-797

Rule IDs

SV-37361r1_rule

The /etc/shadow file contains the list of local system accounts. It is vital to system security and must be protected from unauthorized modification. Failure to give ownership of sensitive files or utilities to root or bin provides the designated owner and unauthorized users with the potential to access sensitive information or change the system configuration which could weaken the system's security posture.System AdministratorECLP-1

Checks: C-36050r1_chk

Check the ownership of the /etc/shadow file. # ls -lL /etc/shadow If the /etc/shadow file is not owned by root, this is a finding.

Fix: F-31294r1_fix

Change the ownership of the /etc/shadow (or equivalent) file. # chown root /etc/shadow

b

The /etc/passwd file must have mode 0644 or less permissive.

AC-6 - Medium - CCI-000225 - V-798 - SV-37344r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001380

Vuln IDs

V-798

Rule IDs

SV-37344r1_rule

If the passwd file is writable by a group-owner or the world, the risk of passwd file compromise is increased. The passwd file contains the list of accounts on the system and associated information.System AdministratorECLP-1

Checks: C-36037r1_chk

Check the mode of the /etc/passwd file. Procedure: # ls -lL /etc/passwd If /etc/passwd has a mode more permissive than 0644, this is a finding.

Fix: F-31280r1_fix

Change the mode of the passwd file to 0644. Procedure: # chmod 0644 /etc/passwd

b

The /etc/shadow (or equivalent) file must have mode 0400.

AC-6 - Medium - CCI-000225 - V-800 - SV-37368r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001420

Vuln IDs

V-800

Rule IDs

SV-37368r1_rule

The /etc/shadow file contains the list of local system accounts. It is vital to system security and must be protected from unauthorized modification. The file also contains password hashes which must not be accessible to users other than root.System AdministratorECLP-1

Checks: C-36056r1_chk

Check the mode of the /etc/shadow file. # ls -lL /etc/shadow If the /etc/shadow file has a mode more permissive than 0400, this is a finding.

Fix: F-31300r1_fix

Change the mode of the /etc/shadow (or equivalent) file. # chmod 0400 /etc/shadow

b

The owner, group-owner, mode, ACL, and location of files with the setuid bit set must be documented using site-defined procedures.

CM-6 - Medium - CCI-000368 - V-801 - SV-37579r4_rule

RMF Control

CM-6

Severity

M

CCI

CCI-000368

Version

GEN002380

Vuln IDs

V-801

Rule IDs

SV-37579r4_rule

All files with the setuid bit set will allow anyone running these files to be temporarily assigned the UID of the file. While many system files depend on these attributes for proper operation, security problems can result if setuid is assigned to programs allowing reading and writing of files, or shell escapes. Only default vendor-supplied executables should have the setuid bit set.trueInformation Assurance OfficerSystem Administrator

Checks: C-36445r7_chk

Check for the presence of aide on the system: # rpm -qa | grep aide If aide is not installed, ask the SA what file integrity tool is being used to check the system. Check the global crontabs for the presence of an "aide" job to run at least weekly, if aide is installed. Otherwise, check for the presence of a cron job to run the alternate file integrity checking application. # grep aide /etc/cron*/* If a tool is being run, then the configuration file for the appropriate tool needs to be checked for selection lines /bin, /sbin, /lib, and /usr. If the file integrity tool is set to check setuid and setgid, this is not a finding. List all setuid files on the system. Procedure: # find / -perm -4000 -exec ls -l {} \; | more Note: Executing these commands may result in large listings of files; the output may be redirected to a file for easier analysis. Ask the SA or ISSO if files with the setuid bit set have been documented. Documentation must include the owner, group-owner, mode, ACL, and location of the files. If any undocumented file has its setuid bit set, this is a finding.

Fix: F-31615r1_fix

Document the files with the suid bit set or unset the suid bit on the executable.

b

The owner, group-owner, mode, ACL and location of files with the setgid bit set must be documented using site-defined procedures.

CM-6 - Medium - CCI-000368 - V-802 - SV-37628r3_rule

RMF Control

CM-6

Severity

M

CCI

CCI-000368

Version

GEN002440

Vuln IDs

V-802

Rule IDs

SV-37628r3_rule

All files with the setgid bit set will allow anyone running these files to be temporarily assigned the GID of the file. While many system files depend on these attributes for proper operation, security problems can result if setgid is assigned to programs allowing reading and writing of files, or shell escapes.trueSystem AdministratorInformation Assurance Officer

Checks: C-36826r4_chk

If STIGID GEN000220 is satisfied, this is not a finding. List all setgid files on the system. Procedure: # find / -perm -2000 -exec ls -l {} \; | more Note: Executing these commands may result in large listings of files; the output may be redirected to a file for easier analysis. Ask the SA or IAO if files with the setgid bit set have been documented. Documentation must include owner, group-owner, mode, ACL, and location. If any undocumented file has its setgid bit set, this is a finding. If a tool is being run then the configuration file for the appropriate tool needs to be checked for selection lines /bin, /sbin, /lib, and /usr. If a file integrity tool is set to check setuid and setgid, this is not a finding.

Fix: F-31664r1_fix

Document the files with the sgid bit set or unset the sgid bit on the executable.

b

The system must be checked weekly for unauthorized setuid files as well as unauthorized modification to authorized setuid files.

CM-3 - Medium - CCI-000318 - V-803 - SV-37592r4_rule

RMF Control

CM-3

Severity

M

CCI

CCI-000318

Version

GEN002400

Vuln IDs

V-803

Rule IDs

SV-37592r4_rule

Files with the setuid bit set will allow anyone running these files to be temporarily assigned the UID of the file. While many system files depend on these attributes for proper operation, security problems can result if setuid is assigned to programs allowing reading and writing of files, or shell escapes.System Administrator

Checks: C-36666r5_chk

Ask the SA for the weekly automated or manual process used to generate a list of setuid files on the system and compare it with the prior list. If no such process is in place, this is a finding. If a file integrity tool is configured to monitor setuid files weekly, this is not a finding. Review the process. If the process does not identify and report changes in setuid files, this is a finding. NOTE: The frequency may be increased to daily, if necessary, in accordance with the contingency plan.

Fix: F-31627r4_fix

Establish a weekly automated or manual process to generate a list of suid files on the system and compare it with the prior list. To create a list of suid files: # find / -perm -4000 > suid-file-list NOTE: The frequency may be increased to daily, if necessary, in accordance with the contingency plan.

b

The system must be checked weekly for unauthorized setgid files as well as unauthorized modification to authorized setgid files.

CM-3 - Medium - CCI-000318 - V-804 - SV-37635r4_rule

RMF Control

CM-3

Severity

M

CCI

CCI-000318

Version

GEN002460

Vuln IDs

V-804

Rule IDs

SV-37635r4_rule

Files with the setgid bit set will allow anyone running these files to be temporarily assigned the group id of the file. While many system files depend on these attributes for proper operation, security problems can result if setgid is assigned to programs allowing reading and writing of files, or shell escapes.System Administrator

Checks: C-36833r6_chk

Ask the SA if a weekly automated or manual process is used to generate a list of setgid files on the system and compare it with the prior list. If no such process is in place, this is a finding. If a file integrity tool is configured to monitor setgid files weekly, this is not a finding. NOTE: The frequency may be increased to daily, if necessary, in accordance with the contingency plan.

Fix: F-31671r5_fix

Establish a weekly automated or manual process to generate a list of setgid files on the system and compare it with the prior list. To create a list of setgid files: # find / -perm -2000 > setgid-file-list NOTE: The frequency may be increased to daily, if necessary, in accordance with the contingency plan.

b

Removable media, remote file systems, and any file system not containing approved setuid files must be mounted with the "nosuid" option.

AC-6 - Medium - CCI-000225 - V-805 - SV-37607r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN002420

Vuln IDs

V-805

Rule IDs

SV-37607r1_rule

The "nosuid" mount option causes the system to not execute setuid files with owner privileges. This option must be used for mounting any file system not containing approved setuid files. Executing setuid files from untrusted file systems, or file systems not containing approved setuid files, increases the opportunity for unprivileged users to attain unauthorized administrative access.System AdministratorECLP-1

Checks: C-36773r2_chk

Check /etc/mtab and verify the "nosuid" mount option is used on file systems mounted from removable media, network shares, or any other file system not containing approved setuid or setgid files. If any of these files systems do not mount with the "nosuid" option, it is a finding.

Fix: F-31642r1_fix

Edit /etc/fstab and add the "nosuid" mount option to all file systems mounted from removable media or network shares, and any file system not containing approved setuid or setgid files.

a

The sticky bit must be set on all public directories.

CM-6 - Low - CCI-000366 - V-806 - SV-37647r1_rule

RMF Control

CM-6

Severity

L

CCI

Version

GEN002500

Vuln IDs

V-806

Rule IDs

SV-37647r1_rule

Failing to set the sticky bit on the public directories allows unauthorized users to delete files in the directory structure. The only authorized public directories are those temporary directories supplied with the system or those designed to be temporary file repositories. The setting is normally reserved for directories used by the system and by users for temporary file storage, (e.g., /tmp), and for directories requiring global read/write access.System AdministratorECCD-1, ECCD-2

Checks: C-36843r1_chk

Check all world-writable directories have the sticky bit set. Procedure: # find / -type d -perm -002 ! -perm -1000 > wwlist If the sticky bit is not set on a world-writable directory, this is a finding.

Fix: F-31680r1_fix

Set the sticky bit on all public directories. Procedure: # chmod 1777 /tmp (Replace /tmp with the public directory missing the sticky bit, if necessary.)

b

All public directories must be owned by root or an application account.

AC-6 - Medium - CCI-000225 - V-807 - SV-37888r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN002520

Vuln IDs

V-807

Rule IDs

SV-37888r1_rule

If a public directory has the sticky bit set and is not owned by a privileged UID, unauthorized users may be able to modify files created by others. The only authorized public directories are those temporary directories supplied with the system or those designed to be temporary file repositories. The setting is normally reserved for directories used by the system and by users for temporary file storage, (e.g., /tmp), and for directories requiring global read/write access.System AdministratorECLP-1

Checks: C-37114r1_chk

Check the ownership of all public directories. Procedure: # find / -type d -perm -1002 -exec ls -ld {} \; If any public directory is not owned by root or an application user, this is a finding.

Fix: F-32382r1_fix

Change the owner of public directories to root or an application account. Procedure: # chown root /tmp (Replace root with an application user and/or /tmp with another public directory as necessary.)

b

The system and user default umask must be 077.

CM-6 - Medium - CCI-000366 - V-808 - SV-37898r2_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN002560

Vuln IDs

V-808

Rule IDs

SV-37898r2_rule

The umask controls the default access mode assigned to newly created files. An umask of 077 limits new files to mode 700 or less permissive. Although umask can be represented as a 4-digit number, the first digit representing special access modes is typically ignored or required to be 0. This requirement applies to the globally configured system defaults and the user defaults for each account on the system.trueIf the default umask is 000 or does not restrict the world-writable permission, this becomes a CAT I finding.System AdministratorECCD-1, ECCD-2

Checks: C-37124r2_chk

NOTE: The following commands must be run in the BASH shell. Check global initialization files for the configured umask value. Procedure: # grep umask /etc/* Check local initialization files for the configured umask value. Procedure: # cut -d: -f6 /etc/passwd |xargs -n1 -IDIR find DIR -name ".*" -type f -maxdepth 1 -exec grep umask {} \; If the system and user default umask is not 077, this a finding. Note: If the default umask is 000 or allows for the creation of world-writable files this becomes a Severity Code I finding.

Fix: F-32392r1_fix

Edit local and global initialization files that contain "umask" and change them to use 077 instead of the current value.

b

Default system accounts must be disabled or removed.

IA-5 - Medium - CCI-000178 - V-810 - SV-37903r1_rule

RMF Control

IA-5

Severity

M

CCI

CCI-000178

Version

GEN002640

Vuln IDs

V-810

Rule IDs

SV-37903r1_rule

Vendor accounts and software may contain backdoors allowing unauthorized access to the system. These backdoors are common knowledge and present a threat to system security if the account is not disabled.System AdministratorIAAC-1

Checks: C-37129r2_chk

Determine if default system accounts (such as those for sys, bin, uucp, nuucp, daemon, smtp) have been disabled. # cat /etc/shadow If an account's password field (which is the second field in the /etc/shadow file) is "*", "*LK*", or is prefixed with a '!', the account is locked or disabled. If there are any unlocked default system accounts this is a finding.

Fix: F-32397r1_fix

Lock the default system account(s). # passwd -l <user>

b

Auditing must be implemented.

AU-12 - Medium - CCI-000169 - V-811 - SV-27270r1_rule

RMF Control

AU-12

Severity

M

CCI

CCI-000169

Version

GEN002660

Vuln IDs

V-811

Rule IDs

SV-27270r1_rule

Without auditing, individual system accesses cannot be tracked and malicious activity cannot be detected and traced back to an individual account.System AdministratorECAR-1, ECAR-2, ECAR-3

Checks: C-28350r1_chk

Determine if auditing is enabled. # ps -ef |grep auditd If the auditd process is not found, this is a finding.

Fix: F-24516r1_fix

Start the auditd service and set it to start on boot. # service auditd start ; chkconfig auditd on

b

System audit logs must be owned by root.

AU-9 - Medium - CCI-000162 - V-812 - SV-37912r1_rule

RMF Control

AU-9

Severity

M

CCI

CCI-000162

Version

GEN002680

Vuln IDs

V-812

Rule IDs

SV-37912r1_rule

Failure to give ownership of system audit log files to root provides the designated owner and unauthorized users with the potential to access sensitive information.System AdministratorECTP-1

Checks: C-37138r1_chk

Perform the following to determine the location of audit logs and then check the ownership. Procedure: # grep "^log_file" /etc/audit/auditd.conf|sed s/^[^\/]*//|xargs stat -c %U:%n If any audit log file is not owned by root, this is a finding.

Fix: F-966r2_fix

Change the ownership of the audit log file(s). Procedure: # chown root <audit log file>

b

System audit logs must have mode 0640 or less permissive.

AU-9 - Medium - CCI-000163 - V-813 - SV-37916r1_rule

RMF Control

AU-9

Severity

M

CCI

CCI-000163

Version

GEN002700

Vuln IDs

V-813

Rule IDs

SV-37916r1_rule

If a user can write to the audit logs, audit trails can be modified or destroyed and system intrusion may not be detected. System audit logs are those files generated from the audit system and do not include activity, error, or other log files created by application software.System AdministratorECTP-1

Checks: C-37142r1_chk

Perform the following to determine the location of audit logs and then check the mode of the files. Procedure: # grep "^log_file" /etc/audit/auditd.conf|sed s/^[^\/]*//|xargs stat -c %a:%n If any audit log file has a mode more permissive than 0640, this is a finding.

Fix: F-967r2_fix

Change the mode of the audit log directories/files. # chmod 0750 <audit directory> # chmod 0640 <audit file>

b

The audit system must be configured to audit failed attempts to access files and programs.

AU-2 - Medium - CCI-000126 - V-814 - SV-38645r1_rule

RMF Control

AU-2

Severity

M

CCI

Version

GEN002720

Vuln IDs

V-814

Rule IDs

SV-38645r1_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System AdministratorECAR-1, ECAR-2, ECAR-3

Checks: C-37782r2_chk

Verify auditd is configured to audit failed file access attempts. There must be an audit rule for each of the access syscalls logging all failed accesses (-F success=0) or there must both an "-F exit=-EPERM" and "-F exit=-EACCES" for each access syscall. Procedure: # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -e "-S creat" | grep -e "-F success=0" # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -e "-S creat" | grep -e "-F exit=-EPERM" # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -e "-S creat" | grep -e "-F exit=-EACCES" If an "-S creat" audit rule with "-F success" does not exist and no separate rules containing "-F exit=-EPERM" and "-F exit=-EACCES" for "creat" exist, then this is a finding.

Fix: F-33035r2_fix

Edit the audit.rules file and add the following line(s) to enable auditing of failed attempts to access files and programs: either: -a exit,always -F arch=<ARCH> -S creat -F success=0 or both: -a exit,always -F arch=<ARCH> -S creat -F exit=-EPERM -a exit,always -F arch=<ARCH> -S creat -F exit=-EACCES Restart the auditd service. # service auditd restart

b

The audit system must be configured to audit files and programs deleted by the user.

AU-2 - Medium - CCI-000126 - V-815 - SV-42185r3_rule

RMF Control

AU-2

Severity

M

CCI

Version

GEN002740

Vuln IDs

V-815

Rule IDs

SV-42185r3_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System Administrator

Checks: C-45161r1_chk

Check the system audit configuration to determine if file and directory deletions are audited. # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -i "unlink" If no results are returned, or the results do not contain "-S unlink", this is a finding.

Fix: F-24531r2_fix

Edit the audit.rules file and add the following line to enable auditing of deletions: -a exit,always -F arch=<ARCH> -S unlink Restart the auditd service. # service auditd restart

b

The audit system must be configured to audit login, logout, and session initiation.

AU-2 - Medium - CCI-000126 - V-818 - SV-37944r1_rule

RMF Control

AU-2

Severity

M

CCI

Version

GEN002800

Vuln IDs

V-818

Rule IDs

SV-37944r1_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System AdministratorECAR-1, ECAR-2, ECAR-3

Checks: C-37225r1_chk

The message types that are always recorded to /var/log/audit/audit.log include LOGIN,USER_LOGIN,USER_START,USER_END among others and do not need to be added to audit_rules. The log files /var/log/faillog and /var/log/lastlog must be protected from tampering of the login records. Procedure: #egrep "faillog|lastlog" /etc/audit/audit.rules|grep "-p (wa|aw)" If both /var/log/faillog and /var/log/lastlog entries do not exist, this is a finding.

Fix: F-32435r1_fix

Ensure logins Procedure: Modify /etc/audit/audit.rules to contain: -w /var/log/faillog -p wa -w /var/log/lastlog -p wa

b

The audit system must be configured to audit all discretionary access control permission modifications.

AU-2 - Medium - CCI-000126 - V-819 - SV-48488r1_rule

RMF Control

AU-2

Severity

M

CCI

Version

GEN002820

Vuln IDs

V-819

Rule IDs

SV-48488r1_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise. System Administrator

Checks: C-45145r1_chk

Check the system's audit configuration. Procedure: # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -i " chmod " If "-S chmod" is not in the result, this is a finding

Fix: F-24555r1_fix

The "-F arch=<ARCH>" restriction is required on dual-architecture systems (such as x86_64). On dual-architecture systems, two separate rules must exist - one for each architecture supported. Use the generic architectures "b32" and "b64" for specifying these rules. On single architecture systems, the "-F arch=<ARCH>" restriction may be omitted, but if present must match either the architecture of the system or its corresponding generic architecture. The architecture of the system may be determined by running "uname -m". See the auditctl(8) manpage for additional details. Any restrictions (such as with "-F") beyond those provided in the example rules are not in strict compliance with this requirement, and are a finding unless justified and documented appropriately. The use of audit keys consistent with the provided example is encouraged to provide for uniform audit logs, however omitting the audit key or using an alternate audit key is not a finding. Procedure: Edit the audit.rules file and add the following lines to enable auditing of discretionary access control permissions modifications. -a exit,always -F arch=<ARCH> -S chmod Restart the auditd service. # service auditd restart

b

The inetd.conf file, xinetd.conf file, and the xinetd.d directory must be owned by root or bin.

AC-6 - Medium - CCI-000225 - V-821 - SV-37406r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003720

Vuln IDs

V-821

Rule IDs

SV-37406r1_rule

Failure to give ownership of sensitive files or utilities to root provides the designated owner and unauthorized users with the potential to access sensitive information or change the system configuration possibly weakening the system's security posture.System AdministratorECLP-1

Checks: C-36089r1_chk

Check the owner of the xinetd configuration files. Procedure: # ls -lL /etc/xinetd.conf # ls -laL /etc/xinetd.d This is a finding if any of the above files or directories are not owned by root or bin.

Fix: F-31336r1_fix

Change the owner of the xinetd configuration files. # chown root /etc/xinetd.conf /etc/xinetd.d/*

b

The xinetd configuration files must have mode 0640 or less permissive.

AC-6 - Medium - CCI-000225 - V-822 - SV-37408r2_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003740

Vuln IDs

V-822

Rule IDs

SV-37408r2_rule

The Internet service daemon configuration files must be protected as malicious modification could cause Denial of Service or increase the attack surface of the system.System Administrator

Checks: C-36091r3_chk

Check the mode of the xinetd configuration files. Procedure: # ls -lL /etc/xinetd.conf # ls -lL /etc/xinetd.d If the mode of the file(s) is more permissive than 0640, this is a finding.

Fix: F-31338r3_fix

Change the mode of the xinetd configuration files. # chmod 0640 /etc/xinetd.conf /etc/xinetd.d/*

b

The services file must be owned by root or bin.

AC-6 - Medium - CCI-000225 - V-823 - SV-37424r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003760

Vuln IDs

V-823

Rule IDs

SV-37424r1_rule

Failure to give ownership of sensitive files or utilities to root or bin provides the designated owner and unauthorized users with the potential to access sensitive information or change the system configuration possibly weakening the system's security posture.System AdministratorECLP-1

Checks: C-36105r1_chk

Check the ownership of the services file. Procedure: # ls -lL /etc/services If the services file is not owned by root or bin, this is a finding.

Fix: F-31351r1_fix

Change the ownership of the services file to root or bin. Procedure: # chown root /etc/services

b

The services file must have mode 0644 or less permissive.

AC-6 - Medium - CCI-000225 - V-824 - SV-37426r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003780

Vuln IDs

V-824

Rule IDs

SV-37426r1_rule

The services file is critical to the proper operation of network services and must be protected from unauthorized modification. Unauthorized modification could result in the failure of network services.System AdministratorECLP-1

Checks: C-36107r1_chk

Check the mode of the services file. Procedure: # ls -lL /etc/services If the services file has a mode more permissive than 0644, this is a finding

Fix: F-31353r1_fix

Change the mode of the services file to 0644 or less permissive. Procedure: # chmod 0644 /etc/services

a

Global initialization files must contain the "mesg -n" or "mesg n" commands.

CM-6 - Low - CCI-000366 - V-825 - SV-37289r1_rule

RMF Control

CM-6

Severity

L

CCI

Version

GEN001780

Vuln IDs

V-825

Rule IDs

SV-37289r1_rule

If the "mesg -n" or "mesg n" command is not placed into the system profile, messaging can be used to cause a Denial of Service attack.System AdministratorECSC-1

Checks: C-35983r1_chk

Check global initialization files for the presence of "mesg -n" or "mesg n". Procedure: # grep "mesg" etc/bashrc /etc/csh.cshrc /etc/csh.login /etc/csh.logout /etc/environment /etc/ksh.kshrc /etc/profile /etc/suid_profile /etc/profile.d/* If no global initialization files contain "mesg -n" or "mesg n", this is a finding.

Fix: F-31237r1_fix

Edit /etc/profile or another global initialization script, and add the "mesg -n" command.

b

The hosts.lpd file (or equivalent) must not contain a + character.

CM-6 - Medium - CCI-000366 - V-827 - SV-37447r2_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN003900

Vuln IDs

V-827

Rule IDs

SV-37447r2_rule

Having the '+' character in the hosts.lpd (or equivalent) file allows all hosts to use local system print resources.System Administrator

Checks: C-36119r2_chk

RHEL uses "cups" print service. Verify remote host access is limited. Procedure: # grep -i Listen /etc/cups/cupsd.conf The /etc/cups/cupsd.conf file must not contain a Listen *:<port> or equivalent line. If the network address of the "Listen" line is unrestricted, this is a finding. # grep -i "Allow From" /etc/cups/cupsd.conf The "Allow From" line within the "<Location />" element should limit access to the printers to @LOCAL and specific hosts. If the "Allow From" line contains "All" this is a finding

Fix: F-31365r1_fix

Configure cups to use only the localhost or specified remote hosts. Procedure: Modify the /etc/cups/cupsd.conf file to "Listen" only to the local machine or a known set of hosts (i.e., Listen localhost:631). Modify the /etc/cups/cupsd.conf file "<Location />" element to "Deny From All" and "Allow from 127.0.0.1" or allowed host addresses. Restart cups: # service cups restart

b

The hosts.lpd (or equivalent) file must be owned by root, bin, sys, or lp.

AC-6 - Medium - CCI-000225 - V-828 - SV-37448r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003920

Vuln IDs

V-828

Rule IDs

SV-37448r1_rule

Failure to give ownership of the hosts.lpd file to root, bin, sys, or lp provides the designated owner, and possible unauthorized users, with the potential to modify the hosts.lpd file. Unauthorized modifications could disrupt access to local printers from authorized remote hosts or permit unauthorized remote access to local printers.System AdministratorECLP-1

Checks: C-36120r1_chk

Check the ownership of the print service configuration file. Procedure: # ls -lL /etc/cups/printers.conf; If no print service configuration file is found, this is not applicable. If the owner of the file is not root, this is a finding

Fix: F-31366r3_fix

Change the owner of the /etc/cups/printers.conf to root. Procedure: # chown root /etc/cups/printers.conf

b

The hosts.lpd (or equivalent) must have mode 0644 or less permissive.

AC-6 - Medium - CCI-000225 - V-829 - SV-37461r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003940

Vuln IDs

V-829

Rule IDs

SV-37461r1_rule

Excessive permissions on the hosts.lpd (or equivalent) file may permit unauthorized modification. Unauthorized modifications could disrupt access to local printers from authorized remote hosts or permit unauthorized remote access to local printers.System AdministratorECLP-1

Checks: C-36127r1_chk

Check the mode of the print service configuration file. Procedure: # ls -lL /etc/cups/printers.conf If no print service configuration file is found, this is not applicable. If the mode of the print service configuration file is more permissive than 0664, this is a finding.

Fix: F-31371r1_fix

Change the mode of the /etc/cups/printers.conf file to 0664 or less permissive. Procedure: # chmod 0664 /etc/cups/printers.conf

b

The alias file must be owned by root.

AC-6 - Medium - CCI-000225 - V-831 - SV-37472r2_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN004360

Vuln IDs

V-831

Rule IDs

SV-37472r2_rule

If the alias file is not owned by root, an unauthorized user may modify the file adding aliases to run malicious code or redirect e-mail.System Administrator

Checks: C-36137r2_chk

If the "sendmail" and "postfix" packages are not installed, this is not applicable. Check the ownership of the alias files. Procedure: for sendmail: # ls -lL /etc/aliases # ls -lL /etc/aliases.db If all the files are not owned by root, this is a finding. for postfix: Verify the location of the alias file. # postconf alias maps This will return the location of the "aliases" file, by default "/etc/postfix/aliases" # ls -lL <postfix aliases file> # ls -lL <postfix aliases.db file> If all the files are not owned by root, this is a finding.

Fix: F-31384r1_fix

Change the owner of the /etc/aliases file to root. Procedure: for sendmail: # chown root /etc/aliases # chown root /etc/aliases.db for postfix # chown root /etc/postfix/aliases # chown root /etc/postfix/aliases.db

b

The alias file must have mode 0644 or less permissive.

AC-6 - Medium - CCI-000225 - V-832 - SV-37475r3_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN004380

Vuln IDs

V-832

Rule IDs

SV-37475r3_rule

Excessive permissions on the aliases file may permit unauthorized modification. If the alias file is modified by an unauthorized user, they may modify the file to run malicious code or redirect e-mail.System Administrator

Checks: C-36141r3_chk

If the "sendmail" and "postfix" packages are not installed, this is not applicable. Check the permissions of the alias file. Procedure: for sendmail: # ls -lL /etc/aliases /etc/aliases.db If an alias file has a mode more permissive than 0644, this is a finding. for postfix: Verify the location of the alias file. # postconf alias_maps This will return the location of the "aliases" file, by default "/etc/postfix/aliases". # ls -lL <postfix aliases file> <postfix aliases.db file> If an alias file has a mode more permissive than 0644, this is a finding.

Fix: F-31387r2_fix

Change the mode of the alias files as needed to function. No higher than 0644. Procedure: for sendmail: # chmod 0644 /etc/aliases /etc/aliases.db for postfix (assuming the default postfix directory): # chmod 0644 /etc/postfix/aliases /etc/postfix/aliases.db

c

Files executed through a mail aliases file must be owned by root and must reside within a directory owned and writable only by root.

AC-6 - High - CCI-000225 - V-833 - SV-37491r1_rule

RMF Control

AC-6

Severity

H

CCI

Version

GEN004400

Vuln IDs

V-833

Rule IDs

SV-37491r1_rule

If a file executed through a mail aliases file is not owned and writable only by root, it may be subject to unauthorized modification. Unauthorized modification of files executed through aliases may allow unauthorized users to attain root privileges.System AdministratorECLP-1

Checks: C-36149r1_chk

Verify the ownership of files referenced within the sendmail aliases file. Procedure: # more /etc/aliases Examine the aliases file for any utilized directories or paths. # ls -lL <directory or file path> Check the owner for any paths referenced. Check if the file or parent directory is owned by root. If not, this is a finding.

Fix: F-31398r1_fix

Edit the /etc/aliases file (alternatively, /usr/lib/sendmail.cf). Locate the entries executing a program. They will appear similar to the following line: Aliasname: : /usr/local/bin/ls (or some other program name) Ensure root owns the programs and the directory(ies) they reside in by using the chown command to change owner to root. Procedure: # chown root <file or directory name>

b

Files executed through a mail aliases file must have mode 0755 or less permissive.

AC-6 - Medium - CCI-000225 - V-834 - SV-37494r2_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN004420

Vuln IDs

V-834

Rule IDs

SV-37494r2_rule

If a file executed through a mail aliases file has permissions greater than 0755, it can be modified by an unauthorized user and may contain malicious code or instructions potentially compromising the system.System Administrator

Checks: C-36152r4_chk

If the "sendmail" package is not installed, this is not applicable. Examine the contents of the /etc/aliases file. Procedure: # more /etc/aliases Examine the aliases file for any referenced programs, which are specified with the pipe (|) symbol. # ls -lL <file referenced from aliases> Check the permissions for any paths referenced. If any file referenced from the aliases file has a mode more permissive than 0755, this is a finding.

Fix: F-31403r2_fix

Use the chmod command to change the access permissions for files executed from the alias file. For example: # chmod 0755 filename

a

Sendmail logging must not be set to less than nine in the sendmail.cf file.

CM-6 - Low - CCI-000366 - V-835 - SV-37497r2_rule

RMF Control

CM-6

Severity

L

CCI

Version

GEN004440

Vuln IDs

V-835

Rule IDs

SV-37497r2_rule

If Sendmail is not configured to log at level 9, system logs may not contain the information necessary for tracking unauthorized use of the sendmail service.System Administrator

Checks: C-36154r3_chk

If the "sendmail" package is not installed, this is not applicable. Check if sendmail logging is set to level nine: Procedure: for sendmail: # grep "O L" /etc/mail/sendmail.cf OR # grep LogLevel /etc/mail/sendmail.cf If logging is set to less than nine, this is a finding. for Postfix: This rule is not applicable to postfix which does not use "log levels" in the same fashion as sendmail.

Fix: F-31405r2_fix

Edit the sendmail.cf file, locate the "O L" or "LogLevel" entry and change it to 9.

b

The system syslog service must log informational and more severe SMTP service messages.

AU-2 - Medium - CCI-000126 - V-836 - SV-37500r3_rule

RMF Control

AU-2

Severity

M

CCI

Version

GEN004460

Vuln IDs

V-836

Rule IDs

SV-37500r3_rule

If informational and more severe SMTP service messages are not logged, malicious activity on the system may go unnoticed.System Administrator

Checks: C-36156r2_chk

Check the syslog configuration file for mail.crit logging configuration. Depending on what system is used for log processing either /etc/syslog.conf or /etc/rsyslog.conf will be the logging configuration file. Procedure: # grep "mail\." /etc/syslog.conf Or: #grep "mail\." /etc/syslog.conf If syslog is not configured to log critical sendmail messages ("mail.crit" or "mail.*"), this is a finding.

Fix: F-31407r4_fix

Edit the syslog.conf or rsyslog.conf file and add a configuration line specifying an appropriate destination for "mail.crit" or "mail.*" syslog messages.

b

The SMTP service log file must be owned by root.

AC-6 - Medium - CCI-000225 - V-837 - SV-37501r3_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN004480

Vuln IDs

V-837

Rule IDs

SV-37501r3_rule

If the SMTP service log file is not owned by root, then unauthorized personnel may modify or delete the file to hide a system compromise.System Administrator

Checks: C-36158r4_chk

Locate any mail log files by checking the syslog configuration file. Procedure: The check procedure is the same for both sendmail and Postfix. Identify any log files configured for the "mail" service (excluding mail.none) at any severity level and check the ownership. Depending on what system is used for log processing, either /etc/syslog.conf or /etc/rsyslog.conf will be the logging configuration file. For syslog: # egrep "mail\.[^n][^/]*" /etc/syslog.conf|sed 's/^[^/]*//'|xargs ls -lL For rsyslog: # egrep "mail\.[^n][^/]*" /etc/rsyslog.conf|sed 's/^[^/]*//'|xargs ls -lL If any mail log file is not owned by root, this is a finding.

Fix: F-31408r1_fix

Change the ownership of the sendmail log file. Procedure: The fix procedure is the same for both sendmail and Postfix. # chown root <sendmail log file>

b

The SMTP service log file must have mode 0644 or less permissive.

AC-6 - Medium - CCI-000225 - V-838 - SV-37502r3_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN004500

Vuln IDs

V-838

Rule IDs

SV-37502r3_rule

If the SMTP service log file is more permissive than 0644, unauthorized users may be allowed to change the log file.System Administrator

Checks: C-36159r4_chk

Check the mode of the SMTP service log file. Procedure: The check procedure is the same for both sendmail and Postfix. Identify any log files configured for the "mail" service (excluding mail.none) at any severity level and check the permissions. Depending on what system is used for log processing, either /etc/syslog.conf or /etc/rsyslog.conf will be the logging configuration file. For syslog: # egrep "mail\.[^n][^/]*" /etc/syslog.conf|sed 's/^[^/]*//'|xargs ls -lL For rsyslog: # egrep "mail\.[^n][^/]*" /etc/rsyslog.conf|sed 's/^[^/]*//'|xargs ls -lL If the log file permissions are greater than 0644, this is a finding.

Fix: F-31410r1_fix

Change the mode of the SMTP service log file. Procedure: The fix procedure is the same for both sendmail and Postfix. # chmod 0644 <sendmail log file>

b

The ftpusers file must exist.

AC-6 - Medium - CCI-000225 - V-840 - SV-51983r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN004880

Vuln IDs

V-840

Rule IDs

SV-51983r1_rule

The ftpusers file contains a list of accounts not allowed to use FTP to transfer files. If this file does not exist, then unauthorized accounts can utilize FTP.System Administrator

Checks: C-36189r1_chk

Check for the existence of the ftpusers file. Procedure: For gssftp: # ls -l /etc/ftpusers For vsftp: # ls -l /etc/vsftpd.ftpusers or # ls -l /etc/vsftpd/ftpusers If the appropriate ftpusers file for the running FTP service does not exist, this is a finding.

Fix: F-45028r1_fix

Create an ftpusers file appropriate for the running FTP service. For gssftp: Create an /etc/ftpusers file containing a list of accounts not authorized for FTP. For vsftp: Create an /etc/vsftpd.ftpusers or /etc/vsftpd/ftpusers (as appropriate) file containing a list of accounts not authorized for FTP.

b

The ftpusers file must contain account names not allowed to use FTP.

AC-6 - Medium - CCI-000225 - V-841 - SV-52091r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN004900

Vuln IDs

V-841

Rule IDs

SV-52091r1_rule

The ftpusers file contains a list of accounts not allowed to use FTP to transfer files. If the file does not contain the names of all accounts not authorized to use FTP, then unauthorized use of FTP may take place.System Administrator

Checks: C-36191r1_chk

Check the contents of the ftpusers file. For gssftp: # more /etc/ftpusers For vsftp: # more /etc/vsftpd.ftpusers /etc/vfsftpd/ftpusers If the system has accounts not allowed to use FTP and not listed in the ftpusers file, this is a finding.

Fix: F-45121r1_fix

For gssftp: Add accounts not allowed to use FTP to the /etc/ftpusers file. For vsftp: Add accounts not allowed to use FTP to the /etc/vsftpd.ftpusers or /etc/vsftpd/ftpusers file (as appropriate).

b

The ftpusers file must be owned by root.

AC-6 - Medium - CCI-000225 - V-842 - SV-37537r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN004920

Vuln IDs

V-842

Rule IDs

SV-37537r1_rule

If the file ftpusers is not owned by root, an unauthorized user may modify the file to allow unauthorized accounts to use FTP.System AdministratorECLP-1

Checks: C-36195r1_chk

Check the ownership of the ftpusers file. Procedure: For gssftp: # ls -l /etc/ftpusers For vsftp: # ls -l /etc/vsftpd.ftpusers /etc/vsftpd/ftpusers If the ftpusers file is not owned by root, this is a finding

Fix: F-31452r1_fix

Change the owner of the ftpusers file to root. For gssftp: # chown root /etc/ftpusers For vsftp: # chown root /etc/vsftpd.ftpusers /etc/vsftpd/ftpusers

b

The ftpusers file must have mode 0640 or less permissive.

AC-6 - Medium - CCI-000225 - V-843 - SV-37542r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN004940

Vuln IDs

V-843

Rule IDs

SV-37542r1_rule

Excessive permissions on the ftpusers file could permit unauthorized modification. Unauthorized modification could result in Denial of Service to authorized FTP users or permit unauthorized users to access the FTP service.System AdministratorECLP-1

Checks: C-36199r1_chk

Check the permissions of the ftpusers file. Procedure: For gssftp: # ls -l /etc/ftpusers For vsftp: # ls -l /etc/vsftpd.ftpusers /etc/vsftpd/ftpusers If the ftpusers file has a mode more permissive than 0640, this is a finding.

Fix: F-31457r1_fix

Change the mode of the ftpusers file to 0640. Procedure: For gssftp: # chmod 0640 /etc/ftpusers For vsftp: # chmod 0640 /etc/vsftpd.ftpusers /etc/vsftpd/ftpusers

a

The FTP daemon must be configured for logging or verbose mode.

AU-3 - Low - CCI-000130 - V-845 - SV-37547r1_rule

RMF Control

AU-3

Severity

L

CCI

CCI-000130

Version

GEN004980

Vuln IDs

V-845

Rule IDs

SV-37547r1_rule

The -l option allows basic logging of connections. The verbose (on HP) and the debug (on Solaris) allow logging of what files the ftp session transferred. This extra logging makes it possible to easily track which files are being transferred onto or from a system. If they are not configured, the only option for tracking is the audit files. The audit files are much harder to read. If auditing is not properly configured, then there would be no record at all of the file transfer transactions.System AdministratorECAR-1, ECAR-2, ECAR-3

Checks: C-36202r2_chk

Find if logging is applied to the ftp daemon. The procedure depends on the implementation of ftpd used by the system. Procedures: For vsftpd: If vsftpd is started by xinetd: #grep vsftpd /etc/xinetd.d/* This will indicate the xinetd.d startup file #grep server_args <vsftpd xinetd.d startup file> This will indicate the vsftpd config file used when starting through xinetd. If the line is missing then "/etc/vsftpd/vsftpd.conf", the default config file, is used. #grep xferlog_enable <vsftpd config file> If "xferlog_enable" is missing or is not set to "yes", this is a finding. If vsftp is not started by xinetd: #grep xferlog_enable /etc/vsftpd/vsftpd.conf If "xferlog_enable" is missing or is not set to "yes", this is a finding. For gssftp: Find if the -l option will be applied when xinetd starts gssftp # grep server_args /etc/xinetd.d/gssftp If the line is missing or does not contain at least one -l, this is a finding.

Fix: F-31461r1_fix

Enable logging by changing ftpd startup or config files. Procedure: The procedure depends on the implementation of ftpd used by the system. For vsftpd: Ensure the server settings in "/etc/vsftpd.conf" (or other configuration file specified by the vaftpd xinetd.d startup file) contains: xferlog_enable = yes For gssftp: If the "disable" server setting is missing or set to "no" in "/etc/xinetd.d/gssftp" then ensure the server settings in "/etc/xinetd.d/gssftp" contains: server_args = -l The -l option may be added up to three times. Each -l will provide increasing verbosity on the log. Refer to the main page for ftpd for more information. For both if started using xinetd: If the "disable" server setting is missing or set to "no" in the /etc/xinetd.d startup file then ensure the server settings contains: log_on_success += DURATION USERID This will log the startup and shutdown of the daemon. log_on_failure += HOST USERID

b

Anonymous FTP must not be active on the system unless authorized.

AC-22 - Medium - CCI-001475 - V-846 - SV-37526r1_rule

RMF Control

AC-22

Severity

M

CCI

CCI-001475

Version

GEN004820

Vuln IDs

V-846

Rule IDs

SV-37526r1_rule

Due to the numerous vulnerabilities inherent in anonymous FTP, it is not recommended. If anonymous FTP must be used on a system, the requirement must be authorized and approved in the system accreditation package.trueSystem AdministratorInformation Assurance OfficerECSC-1

Checks: C-36185r1_chk

Attempt to log into this host with a user name of anonymous and a password of guest (also try the password of guest@mail.com). If the logon is successful and the use of anonymous ftp has not been documented and approved by the IAO, this is a finding. Procedure: # ftp localhost Name: anonymous 530 Guest login not allowed on this machine.

Fix: F-31440r1_fix

Configure the FTP service to not permit anonymous logins.

c

The TFTP daemon must operate in "secure mode" which provides access only to a single directory on the host file system.

CM-6 - High - CCI-000366 - V-847 - SV-37560r1_rule

RMF Control

CM-6

Severity

H

CCI

Version

GEN005080

Vuln IDs

V-847

Rule IDs

SV-37560r1_rule

Secure mode limits TFTP requests to a specific directory. If TFTP is not running in secure mode, it may be able to write to any file or directory and may seriously impair system integrity, confidentiality, and availability.System AdministratorECSC-1

Checks: C-36211r1_chk

# grep server_args /etc/xinetd.d/tftp If the "-s" parameter is not specified, this is a finding.

Fix: F-31470r1_fix

Edit /etc/xinetd.d/tftp file and specify the "-s" parameter in server_args.

c

The TFTP daemon must have mode 0755 or less permissive.

AC-6 - High - CCI-000225 - V-848 - SV-37564r1_rule

RMF Control

AC-6

Severity

H

CCI

Version

GEN005100

Vuln IDs

V-848

Rule IDs

SV-37564r1_rule

If TFTP runs with the setuid or setgid bit set, it may be able to write to any file or directory and may seriously impair system integrity, confidentiality, and availability.System AdministratorECPA-1

Checks: C-36213r1_chk

Check the mode of the TFTP daemon. Procedure: # grep "server " /etc/xinetd.d/tftp # ls -lL <in.tftpd binary> If the mode of the file is more permissive than 0755, this is a finding.

Fix: F-31473r1_fix

Change the mode of the TFTP daemon. Procedure: # chmod 0755 <in.tftpd binary>

b

The TFTP daemon must be configured to vendor specifications, including a dedicated TFTP user account, a non-login shell such as /bin/false, and a home directory owned by the TFTP user.

AC-6 - Medium - CCI-000225 - V-849 - SV-37674r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN005120

Vuln IDs

V-849

Rule IDs

SV-37674r1_rule

If TFTP has a valid shell, it increases the likelihood someone could log on to the TFTP account and compromise the system.System AdministratorECSC-1

Checks: C-36862r1_chk

Check the /etc/passwd file to determine if TFTP is configured properly. Procedure: Check if TFTP if used. # grep disable /etc/xinetd.d/tftp If the file does not exist or the returned line indicates "yes", then this is not a finding. Otherwise, if the returned line indicates "no" then TFTP is enabled and must use a dedicated "tftp" user. # grep user /etc/xinetd.d/tftp If the returned line indicates a user other than the dedicated "tftp" user, this is a finding. # grep tftp /etc/passwd If a "tftp" user account does not exist and TFTP is active, this is a finding. Check the user shell for the "tftp" user. If it is not /bin/false or equivalent, this is a finding. Check the home directory assigned to the "tftp" user. If no home directory is set, or the directory specified is not dedicated to the use of the TFTP service, this is a finding.

Fix: F-31798r1_fix

Configure TFTP to use a dedicated "tftp" user. Procedure: Create a dedicated "tftp" user account if none exists. Assign a non-login shell to the "tftp" user account, such as /bin/false. Assign a home directory to the "tftp" user account. Edit /etc/xinetd.d/tftp to have "tftp" as the value of the "user" parameter.

b

Any X Windows host must write .Xauthority files.

CM-2 - Medium - CCI-000297 - V-850 - SV-37678r3_rule

RMF Control

CM-2

Severity

M

CCI

CCI-000297

Version

GEN005160

Vuln IDs

V-850

Rule IDs

SV-37678r3_rule

.Xauthority files ensure the user is authorized to access specific X Windows host. If .Xauthority files are not used, it may be possible to obtain unauthorized access to the X Windows host.System Administrator

Checks: C-36865r5_chk

Check for .Xauthority or .xauth files being utilized by looking for such files in the home directory of a user. Procedure: # find / -name '.xauth*' | more If no .xauth files are found in a user's home directory, ensure that Xwindows is not active on the system by performing the command: # ps -ef | grep X If Xwindows is not running, this rule is not applicable. If the .Xauthority or .xauth (followed by apparently random characters) files do not exist, ask the SA if the user is using Xwindows. If the user is utilizing Xwindows and none of these files exist, this is a finding.

Fix: F-31811r2_fix

Ensure the X Windows host is configured to write .Xauthority files into user home directories. Edit the Xaccess file. Ensure the line writing the .Xauthority file is uncommented.

b

The Network Information System (NIS) protocol must not be used.

AC-17 - Medium - CCI-001435 - V-867 - SV-37742r1_rule

RMF Control

AC-17

Severity

M

CCI

CCI-001435

Version

GEN006400

Vuln IDs

V-867

Rule IDs

SV-37742r1_rule

Due to numerous security vulnerabilities existing within NIS, it must not be used. Possible alternative directory services are NIS+ and LDAP.System AdministratorInformation Assurance OfficerECSC-1

Checks: C-36937r2_chk

Perform the following to determine if NIS is active on the system: # ps -ef | grep ypbind If NIS is found active on the system, this is a finding.

Fix: F-32202r1_fix

Disable the use of NIS/NIS+. Use as a replacement Kerberos or LDAP.

a

All interactive users must be assigned a home directory in the /etc/passwd file.

AC-6 - Low - CCI-000225 - V-899 - SV-37375r1_rule

RMF Control

AC-6

Severity

L

CCI

Version

GEN001440

Vuln IDs

V-899

Rule IDs

SV-37375r1_rule

If users do not have a valid home directory, there is no place for the storage and control of files they own.System AdministratorECSC-1

Checks: C-36062r1_chk

Use pwck to verify home directory assignments are present. # pwck If any user is not assigned a home directory, this is a finding.

Fix: F-31306r1_fix

Assign a home directory to any user without one.

a

All interactive user home directories defined in the /etc/passwd file must exist.

AC-6 - Low - CCI-000225 - V-900 - SV-37379r1_rule

RMF Control

AC-6

Severity

L

CCI

Version

GEN001460

Vuln IDs

V-900

Rule IDs

SV-37379r1_rule

If a user has a home directory defined that does not exist, the user may be given the / directory, by default, as the current working directory upon logon. This could create a Denial of Service because the user would not be able to perform useful tasks in this location.System AdministratorECSC-1

Checks: C-36066r1_chk

Use pwck to verify assigned home directories exist. # pwck If any user's assigned home directory does not exist, this is a finding.

Fix: F-31310r1_fix

If a user has no home directory, determine why. If possible, delete accounts without a home directory. If the account is valid, then create the home directory using the appropriate system administration utility or manually. For instance: mkdir directoryname; copy the skeleton files into the directory; chown accountname for the new directory and the skeleton files. Document all changes.

b

All user home directories must have mode 0750 or less permissive.

AC-6 - Medium - CCI-000225 - V-901 - SV-37154r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001480

Vuln IDs

V-901

Rule IDs

SV-37154r1_rule

Excessive permissions on home directories allow unauthorized access to user files.System AdministratorECLP-1

Checks: C-37524r1_chk

Check the home directory mode of each user in /etc/passwd. Procedure: # cut -d: -f6 /etc/passwd|sort|uniq|xargs -n1 ls -ld If a user home directory's mode is more permissive than 0750, this is a finding. Note: Application directories are allowed and may need 0755 permissions (or greater) for correct operation.

Fix: F-32772r1_fix

Change the mode of user home directories to 0750 or less permissive. Procedure (example): # chmod 0750 <home directory> Note: Application directories are allowed and may need 0755 permissions (or greater) for correct operation.

b

All interactive user home directories must be owned by their respective users.

AC-6 - Medium - CCI-000225 - V-902 - SV-37163r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001500

Vuln IDs

V-902

Rule IDs

SV-37163r1_rule

If users do not own their home directories, unauthorized users could access user files.System AdministratorECLP-1

Checks: C-37526r1_chk

Check the ownership of each user home directory listed in the /etc/passwd file. Procedure: # cut -d : -f 6 /etc/passwd | xargs -n1 ls -ld If any user home directory is not owned by the assigned user, this is a finding.

Fix: F-1056r2_fix

Change the owner of a user's home directory to its assigned user. Procedure: # chown <user> <home directory>

b

All interactive user home directories must be group-owned by the home directory owner's primary group.

AC-6 - Medium - CCI-000225 - V-903 - SV-37168r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001520

Vuln IDs

V-903

Rule IDs

SV-37168r1_rule

If the Group Identifier (GID) of the home directory is not the same as the GID of the user, this would allow unauthorized access to files.System AdministratorECLP-1

Checks: C-37527r2_chk

Check the group ownership for each user in the /etc/passwd file. Procedure: # cut -d : -f 6 /etc/passwd | xargs -n1 ls -ld If any user home directory is not group-owned by the assigned user's primary group, this is a finding. Home directories for application accounts requiring different group ownership must be documented using site-defined procedures.

Fix: F-32773r1_fix

Change the group-owner for user home directories to the primary group of the assigned user. Procedure: Find the primary group of the user (GID) which is the fourth field of the user entry in /etc/passwd. # chgrp <GID> <user home directory> Document all changes.

b

All local initialization files must be owned by the home directorys user or root.

AC-6 - Medium - CCI-000225 - V-904 - SV-37430r3_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001860

Vuln IDs

V-904

Rule IDs

SV-37430r3_rule

Local initialization files are used to configure the user's shell environment upon login. Malicious modification of these files could compromise accounts upon logon.System Administrator

Checks: C-35939r3_chk

NOTE: The following commands must be run in the BASH shell. Check the ownership of local initialization files. Procedure: # ls -al /<usershomedirectory>/.login # ls -al /<usershomedirectory>/.cshrc # ls -al /<usershomedirectory>/.logout # ls -al /<usershomedirectory>/.profile # ls -al /<usershomedirectory>/.bash_profile # ls -al /<usershomedirectory>/.bashrc # ls -al /<usershomedirectory>/.bash_logout # ls -al /<usershomedirectory>/.env # ls -al /<usershomedirectory>/.dtprofile # ls -al /<usershomedirectory>/.dispatch # ls -al /<usershomedirectory>/.emacs # ls -al /<usershomedirectory>/.exrc # find /<usershomedirectory>/.dt ! -fstype nfs ! -user <username> -exec ls -ld {} \; If local initialization files are not owned by the home directory's user, this is a finding.

Fix: F-31196r2_fix

Change the ownership of the startup and login files in the user's directory to the user or root, as appropriate. Examine each user's home directory and verify all filenames beginning with "." are owned by the owner of the directory or root. If they are not, use the chown command to change the owner to the user and research the reasons why the owners were not assigned as required. Procedure: # chown username .filename Document all changes.

b

All local initialization files must have mode 0740 or less permissive.

AC-6 - Medium - CCI-000225 - V-905 - SV-37431r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001880

Vuln IDs

V-905

Rule IDs

SV-37431r1_rule

Local initialization files are used to configure the user's shell environment upon login. Malicious modification of these files could compromise accounts upon logon.System AdministratorECLP-1

Checks: C-36108r1_chk

Check the modes of local initialization files. Procedure: # ls -al /<usershomedirectory>/.bashrc # ls -al /<usershomedirectory>/.bash_login # ls -al /<usershomedirectory>/.bash_logout # ls -al /<usershomedirectory>/.bash_profile # ls -al /<usershomedirectory>/.cshrc # ls -al /<usershomedirectory>/.kshrc # ls -al /<usershomedirectory>/.login # ls -al /<usershomedirectory>/.logout # ls -al /<usershomedirectory>/.profile # ls -al /<usershomedirectory>/.tcshrc # ls -al /<usershomedirectory>/.env # ls -al /<usershomedirectory>/.dtprofile (permissions should be 0755) # ls -al /<usershomedirectory>/.dispatch # ls -al /<usershomedirectory>/.emacs # ls -al /<usershomedirectory>/.exrc # find /<usershomedirectory>/.dt ! -fstype nfs $ -perm -0002 -o -perm -0020 $ -exec ls -ld {} \; (permissions not to be more permissive than 0755) If local initialization files are more permissive than 0740 or the .dt directory is more permissive than 0755 or the .dtprofile file is more permissive than 0755, this is a finding.

Fix: F-31202r1_fix

Ensure user startup files have permissions of 0740 or more restrictive. Examine each user's home directory and verify all file names beginning with "." have access permissions of 0740 or more restrictive. If they do not, use the chmod command to correct the vulnerability. Procedure: # chmod 0740 .filename Note: The period is part of the file name and is required.

b

All run control scripts must have mode 0755 or less permissive.

AC-6 - Medium - CCI-000225 - V-906 - SV-37192r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001580

Vuln IDs

V-906

Rule IDs

SV-37192r1_rule

If the startup files are writable by other users, they could modify the startup files to insert malicious commands into the startup files.System AdministratorECLP-1

Checks: C-37531r1_chk

Check run control script modes. # cd /etc # ls -lL rc* # cd /etc/init.d # ls -l If any run control script has a mode more permissive than 0755, this is a finding.

Fix: F-32777r1_fix

Ensure all system startup files have mode 0755 or less permissive. Examine the "rc" files, and all files in the rc1.d (rc2.d, and so on) directories, and in the /etc/init.d directory to ensure they are not world-writable. If they are world-writable, use the chmod command to correct the vulnerability and research why they are world-writable. Procedure: # chmod 755 <startup file>

b

Run control scripts' executable search paths must contain only absolute paths.

CM-6 - Medium - CCI-000366 - V-907 - SV-37202r3_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN001600

Vuln IDs

V-907

Rule IDs

SV-37202r3_rule

The executable search path (typically the PATH environment variable) contains a list of directories for the shell to search to find executables. If this path includes the current working directory or other relative paths, executables in these directories may be executed instead of system commands. This variable is formatted as a colon-separated list of directories. If there is an empty entry, such as a leading or trailing colon, or two consecutive colons, this is interpreted as the current working directory. Paths starting with a slash (/) are absolute paths.System Administrator

Checks: C-37533r5_chk

Verify run control scripts' library search paths. # grep -r '\bPATH\b' /etc/rc* /etc/init.d This variable is formatted as a colon-separated list of directories. If there is an empty entry, such as a leading or trailing colon, or two consecutive colons, this is a finding. If an entry begins with a character other than a slash (/) or other than "$PATH", it is a relative path, and this is a finding.

Fix: F-32779r2_fix

Edit the run control script and remove the relative path entry from the executable search path variable.

c

Run control scripts must not execute world-writable programs or scripts.

AC-6 - High - CCI-000225 - V-910 - SV-38154r2_rule

RMF Control

AC-6

Severity

H

CCI

Version

GEN001640

Vuln IDs

V-910

Rule IDs

SV-38154r2_rule

World-writable files could be modified accidentally or maliciously to compromise system integrity.System Administrator

Checks: C-402r9_chk

Check the permissions on the files or scripts executed from system startup scripts to see if they are world-writable. Create a list of all potential run command level scripts. # ls -l /etc/init.d/* | tr '\011' ' ' | tr -s ' ' | cut -f 9,9 -d " " OR # ls -l /sbin/init.d/* | tr '\011' ' ' | tr -s ' ' | cut -f 9,9 -d " " Create a list of world writeable files. # find / -perm -002 -type f >> worldWriteableFileList Determine if any of the world writeable files in worldWriteableFileList are called from the run command level scripts. Note: Depending upon the number of scripts vs world writeable files, it may be easier to inspect the scripts manually. # more `ls -l /etc/init.d/* | tr '\011' ' ' | tr -s ' ' | cut -f 9,9 -d " "` OR # more `ls -l /sbin/init.d/* | tr '\011' ' ' | tr -s ' ' | cut -f 9,9 -d " "` If any system startup script executes any file or script that is world-writable, this is a finding.

Fix: F-1064r2_fix

Remove the world-writable permission from programs or scripts executed by run control scripts. Procedure: # chmod o-w <program or script executed from run control script>

b

There must be no .netrc files on the system.

IA-5 - Medium - CCI-000196 - V-913 - SV-37436r1_rule

RMF Control

IA-5

Severity

M

CCI

CCI-000196

Version

GEN002000

Vuln IDs

V-913

Rule IDs

SV-37436r1_rule

Unencrypted passwords for remote FTP servers may be stored in .netrc files. Policy requires passwords be encrypted in storage and not used in access scripts.System AdministratorIAIA-1, IAIA-2

Checks: C-36051r1_chk

Check the system for the existence of any .netrc files. Procedure: # find / -name .netrc If any .netrc file exists, this is a finding.

Fix: F-31295r1_fix

Remove the .netrc file(s). Procedure: # find / -name .netrc # rm <.netrc file>

a

All files and directories contained in interactive user home directories must be owned by the home directory's owner.

AC-6 - Low - CCI-000225 - V-914 - SV-37175r1_rule

RMF Control

AC-6

Severity

L

CCI

Version

GEN001540

Vuln IDs

V-914

Rule IDs

SV-37175r1_rule

If users do not own the files in their directories, unauthorized users may be able to access them. Additionally, if files are not owned by the user, this could be an indication of system compromise.trueSystem AdministratorInformation Assurance OfficerECCD-1, ECCD-2

Checks: C-37528r1_chk

For each user in the /etc/passwd file, check for the presence of files and directories within the user's home directory not owned by the home directory owner. Procedure: # find /<usershomedirectory> ! -fstype nfs ! -user <username> ! $ -name .bashrc -o -name .bash_login -o -name .bash_logout -o -name .bash_profile -o -name .cshrc -o -name .kshrc -o -name .login -o -name .logout -o -name .profile -o -name .tcshrc -o -name .env -o -name .dtprofile -o -name .dispatch -o -name .emacs -o -name .exrc $ -exec ls -ld {} \; If user home directories contain files or directories not owned by the home directory owner, this is a finding.

Fix: F-32774r1_fix

Change the ownership of files and directories in user home directories to the owner of the home directory. Procedure: # chown accountowner filename

a

All files and directories contained in user home directories must have mode 0750 or less permissive.

AC-6 - Low - CCI-000225 - V-915 - SV-37183r1_rule

RMF Control

AC-6

Severity

L

CCI

Version

GEN001560

Vuln IDs

V-915

Rule IDs

SV-37183r1_rule

Excessive permissions allow unauthorized access to user files. trueInformation Assurance OfficerSystem AdministratorECLP-1

Checks: C-37529r1_chk

For each user in the /etc/passwd file, check for files and directories with a mode more permissive than 0750. Procedure: # find /<usershomedirectory> ! -fstype nfs ! $ -name .bashrc -o -name .bash_login -o -name .bash_logout -o -name .bash_profile -o -name .cshrc -o -name .kshrc -o -name .login -o -name .logout -o -name .profile -o -name .tcshrc -o -name .env -o -name .dtprofile -o -name .dispatch -o -name .emacs -o -name .exrc $ $ -perm -0001 -o -perm -0002 -o -perm -0004 -o -perm -0020 -o -perm -2000 -o -perm -4000 $ -exec ls -ld {} \; If user home directories contain files or directories more permissive than 0750, this is a finding.

Fix: F-32775r1_fix

Change the mode of files and directories within user home directories to 0750. Procedure: # chmod 0750 filename Document all changes.

b

The /etc/shells (or equivalent) file must exist.

CM-6 - Medium - CCI-000366 - V-916 - SV-37390r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN002120

Vuln IDs

V-916

Rule IDs

SV-37390r1_rule

The shells file (or equivalent) lists approved default shells. It helps provide layered defense to the security approach by ensuring users cannot change their default shell to an unauthorized unsecure shell.System AdministratorECSC-1

Checks: C-36077r1_chk

Verify /etc/shells exists. # ls -l /etc/shells If the file does not exist, this is a finding.

Fix: F-31321r1_fix

Create a /etc/shells file containing a list of valid system shells. Consult vendor documentation for an appropriate list of system shells. Procedure: # echo "/bin/bash" >> /etc/shells # echo "/bin/csh" >> /etc/shells (Repeat as necessary for other shells.)

b

All shells referenced in /etc/passwd must be listed in the /etc/shells file, except any shells specified for the purpose of preventing logins.

CM-6 - Medium - CCI-000366 - V-917 - SV-37393r2_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN002140

Vuln IDs

V-917

Rule IDs

SV-37393r2_rule

The shells file lists approved default shells. It helps provide layered defense to the security approach by ensuring users cannot change their default shell to an unauthorized unsecure shell.System Administrator

Checks: C-36080r3_chk

Confirm the login shells referenced in the /etc/passwd file are listed in the /etc/shells file. Procedure: Determine which shells are permitted for use by users: # more /etc/shells Note: /usr/bin/false, /bin/false, /dev/null, /sbin/nologin, /bin/sync, /sbin/halt, /sbin/shutdown, (and equivalents) cannot be placed in the /etc/shells file. Determine which shells are being used: # more /etc/passwd (optionally shells found in /etc/passwd can be grepped for in /etc/shells) If any shells are found that are not in /etc/shells, or if false shells are found in /etc/shells, then this is a finding.

Fix: F-31324r3_fix

Use the "chsh" utility or edit the /etc/passwd file and correct the error by changing the default shell of the account in error to an acceptable shell name contained in the /etc/shells file. Example: # chsh -s /bin/bash testuser

b

Accounts must be locked upon 35 days of inactivity.

AC-2 - Medium - CCI-000017 - V-918 - SV-37314r2_rule

RMF Control

AC-2

Severity

M

CCI

CCI-000017

Version

GEN000760

Vuln IDs

V-918

Rule IDs

SV-37314r2_rule

On some systems, accounts with disabled passwords still allow access using rcp, remsh, or rlogin through equivalent remote hosts. All that is required is the remote host name and the user name match an entry in a hosts.equiv file and have a .rhosts file in the user directory. Using a shell called /bin/false or /dev/null (or an equivalent) will add a layered defense. Non-interactive accounts on the system, such as application accounts, may be documented exceptions.trueSystem AdministratorIAAC-1

Checks: C-36007r4_chk

Indications of inactive accounts are those that have no entries in the "last" log. Check the date in the "last" log to verify it is within the last 35 days or the maximum numbers of days set by the site if more restrictive. If an inactive account is not disabled via an entry in the password field in the /etc/passwd or /etc/shadow (or equivalent), check the /etc/passwd file to check if the account has a valid shell. The passwd command can also be used to list a status for an account. For example, the following may be used to provide status information on each local account: NOTE: The following must be done in the BASH shell. # cut -d: -f1 /etc/passwd | xargs -n1 passwd -S If an inactive account is found not disabled, this is a finding.

Fix: F-31259r2_fix

All inactive accounts will have /sbin/nologin (or an equivalent), as the default shell in the /etc/passwd file and have the password disabled. Examine the user accounts using the "last" command. Note the date of last login for each account. If any (other than system and application accounts) exceed 35 days or the maximum number of days set by the site, not to exceed 35 days, then disable the accounts using system-config-users tool. Alternately place a shell field of /sbin/nologin /bin/false or /dev/null in the passwd file entry for the account.

b

All shell files must be owned by root or bin.

AC-6 - Medium - CCI-000225 - V-921 - SV-37396r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN002200

Vuln IDs

V-921

Rule IDs

SV-37396r1_rule

If shell files are owned by users other than root or bin, they could be modified by intruders or malicious users to perform unauthorized actions.System AdministratorECLP-1

Checks: C-36081r1_chk

Check the ownership of the system shells. # cat /etc/shells | xargs -n1 ls -l If any shell is not owned by root or bin, this is a finding.

Fix: F-31328r1_fix

Change the ownership of the shell with incorrect ownership. # chown root <shell>

c

All shell files must have mode 0755 or less permissive.

AC-6 - High - CCI-000225 - V-922 - SV-37403r1_rule

RMF Control

AC-6

Severity

H

CCI

Version

GEN002220

Vuln IDs

V-922

Rule IDs

SV-37403r1_rule

Shells with world/group write permissions give the ability to maliciously modify the shell to obtain unauthorized access.System AdministratorECLP-1

Checks: C-36087r1_chk

If /etc/shells exists, check the group ownership of each shell referenced. # cat /etc/shells | xargs -n1 ls -l Otherwise, check any shells found on the system. # find / -name "*sh" | xargs -n1 ls -l If a shell has a mode more permissive than 0755, this is a finding.

Fix: F-31334r1_fix

Change the mode of the shell. # chmod 0755 <shell>

a

The system must be checked for extraneous device files at least weekly.

CM-3 - Low - CCI-000318 - V-923 - SV-37543r3_rule

RMF Control

CM-3

Severity

L

CCI

CCI-000318

Version

GEN002260

Vuln IDs

V-923

Rule IDs

SV-37543r3_rule

If an unauthorized device is allowed to exist on the system, there is the possibility the system may perform unauthorized operations.System AdministratorInformation Assurance Officer

Checks: C-36198r4_chk

Determine if there are any device files outside of /dev: # find / -type b -o -type c |more Check for the presence of an aide on the system: # rpm -qa | grep aide If aide is not installed, ask the SA what file integrity tool is being used to check the system. Check the global crontabs for the presence of an "aide" job to run at least weekly, if aide is installed. Otherwise, check for the presence of a cron job to run the alternate file integrity checking application. # grep aide /etc/cron*/* If a tool is being run, then the configuration file for the appropriate tool needs to be checked for selection lines for /dev and any other directories/subdirectories that contain device files. Review the process to determine if the system is checked for extraneous device files on a weekly basis. If no weekly automated or manual process is in place, this is a finding. If the process is not identifying extraneous device files, this is a finding.

Fix: F-31458r2_fix

Establish a weekly automated or manual process to create a list of device files on the system and determine if any files have been added, moved, or deleted since the last list was generated. A list of device files can be generated with this command: # find / -type b -o -type c > device-file-list

b

Device files and directories must only be writable by users with a system account or as configured by the vendor.

AC-6 - Medium - CCI-000225 - V-924 - SV-37553r3_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN002280

Vuln IDs

V-924

Rule IDs

SV-37553r3_rule

System device files in writable directories could be modified, removed, or used by an unprivileged user to control system hardware.System Administrator

Checks: C-36204r3_chk

Find all world-writable device files existing anywhere on the system. Procedure: # find / -perm -2 -a $ -type b -o -type c $ > devicelist Check the permissions on the directories above subdirectories containing device files. If any of the device files or their parent directories are world-writable, excepting device files specifically intended to be world-writable such as /dev/null, this is a finding. These world-writable files on installation are intended to be world-writable: /dev/full /dev/null /selinux/null /dev/ptmx /dev/random /dev/tty /dev/vsock /dev/zero /dev/log

Fix: F-31464r1_fix

Remove the world-writable permission from the device file(s). Procedure: # chmod o-w <device file> Document all changes.

b

Device files used for backup must only be readable and/or writable by root or the backup user.

AC-6 - Medium - CCI-000225 - V-925 - SV-37558r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN002300

Vuln IDs

V-925

Rule IDs

SV-37558r1_rule

System backups could be accidentally or maliciously overwritten and destroy the ability to recover the system if a compromise should occur. Unauthorized users could also copy system files.trueInformation Assurance OfficerSystem AdministratorECCD-1, ECCD-2

Checks: C-36209r4_chk

Check the system for world-writable device files. Procedure: # find / -perm -2 -a $ -type b -o -type c $ -exec ls -ld {} \; Ask the SA to identify any device files used for backup purposes. If any device file(s) used for backup are writable by users other than root or the designated backup user, this is a finding.

Fix: F-31469r1_fix

Use the chmod command to remove the world-writable bit from the backup device files. Procedure: # chmod o-w <back device filename> Document all changes.

b

The Network File System (NFS) export configuration file must be owned by root.

AC-6 - Medium - CCI-000225 - V-928 - SV-37936r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN005740

Vuln IDs

V-928

Rule IDs

SV-37936r1_rule

Failure to give ownership of the NFS export configuration file to root provides the designated owner and possible unauthorized users with the potential to change system configuration which could weaken the system's security posture.System AdministratorECLP-1

Checks: C-37200r1_chk

Check the owner of the exports file. Example: # ls -lL /etc/exports If the export configuration file is not owned by root, this is a finding.

Fix: F-32428r1_fix

Change the owner of the exports file to root. Example: # chown root /etc/exports

a

The Network File System (NFS) export configuration file must have mode 0644 or less permissive.

AC-6 - Low - CCI-000225 - V-929 - SV-37943r1_rule

RMF Control

AC-6

Severity

L

CCI

Version

GEN005760

Vuln IDs

V-929

Rule IDs

SV-37943r1_rule

Excessive permissions on the NFS export configuration file could allow unauthorized modification of the file, which could result in Denial of Service to authorized NFS exports and the creation of additional unauthorized exports.System AdministratorECCD-1, ECCD-2, ECLP-1

Checks: C-37223r1_chk

# ls -lL /etc/exports If the file has a mode more permissive than 0644, this is a finding.

Fix: F-32434r1_fix

# chmod 0644 /etc/exports

b

All Network File System (NFS) exported system files and system directories must be owned by root.

AC-6 - Medium - CCI-000225 - V-931 - SV-37849r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN005800

Vuln IDs

V-931

Rule IDs

SV-37849r1_rule

Failure to give ownership of sensitive files or directories to root provides the designated owner and possible unauthorized users with the potential to access sensitive information or change system configuration which could weaken the system's security posture.System Administrator

Checks: C-37045r1_chk

Check for NFS exported file systems. Procedure: # cat /etc/exports For each file system displayed, check the ownership. # ls -lLa <exported file system path> If the files and directories are not owned by root, this is a finding.

Fix: F-32313r1_fix

Change the ownership of exported file systems not owned by root. Procedure: # chown root <path>

b

The Network File System (NFS) anonymous UID and GID must be configured to values without permissions.

AC-14 - Medium - CCI-000062 - V-932 - SV-37854r1_rule

RMF Control

AC-14

Severity

M

CCI

CCI-000062

Version

GEN005820

Vuln IDs

V-932

Rule IDs

SV-37854r1_rule

When an NFS server is configured to deny remote root access, a selected UID and GID are used to handle requests from the remote root user. The UID and GID should be chosen from the system to provide the appropriate level of non-privileged access.System AdministratorECSC-1

Checks: C-37049r1_chk

Check if the 'anonuid' and 'anongid' options are set correctly for exported file systems. List exported filesystems: # exportfs -v Each of the exported file systems should include an entry for the 'anonuid=' and 'anongid=' options set to "-1" or an equivalent (60001, 65534, or 65535). If appropriate values for 'anonuid' or 'anongid' are not set, this is a finding.

Fix: F-32316r1_fix

Edit "/etc/exports" and set the "anonuid=-1" and "anongid=-1" options for exports lacking it. Re-export the filesystems.

b

The Network File System (NFS) server must be configured to restrict file system access to local hosts.

CM-6 - Medium - CCI-000366 - V-933 - SV-37857r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN005840

Vuln IDs

V-933

Rule IDs

SV-37857r1_rule

The NFS access option limits user access to the specified level. This assists in protecting exported file systems. If access is not restricted, unauthorized hosts may be able to access the system's NFS exports.System AdministratorECSC-1

Checks: C-37061r1_chk

Check the permissions on exported NFS file systems. Procedure: # exportfs -v If the exported file systems do not contain the 'rw' or 'ro' options specifying a list of hosts or networks, this is a finding.

Fix: F-32328r1_fix

Edit /etc/exports and add ro and/or rw options (as appropriate) specifying a list of hosts or networks which are permitted access. Re-export the file systems.

b

The Network File System (NFS) server must not allow remote root access.

AC-6 - Medium - CCI-000225 - V-935 - SV-37859r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN005880

Vuln IDs

V-935

Rule IDs

SV-37859r1_rule

If the NFS server allows root access to local file systems from remote hosts, this access could be used to compromise the system.Information Assurance ManagerInformation Assurance OfficerSystem AdministratorEBRP-1

Checks: C-37065r1_chk

List the exports. # cat /etc/exports If any export contains "no_root_squash" or does not contain "root_squash" or "all_squash", this is a finding.

Fix: F-32333r1_fix

Edit the "/etc/exports" file and add "root_squash" (or "all_squash") and remove "no_root_squash".

b

The "nosuid" option must be enabled on all Network File System (NFS) client mounts.

AC-6 - Medium - CCI-000225 - V-936 - SV-37860r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN005900

Vuln IDs

V-936

Rule IDs

SV-37860r1_rule

Enabling the nosuid mount option prevents the system from granting owner or group-owner privileges to programs with the suid or sgid bit set. If the system does not restrict this access, users with unprivileged access to the local system may be able to acquire privileged access by executing suid or sgid files located on the mounted NFS file system.Information Assurance OfficerSystem AdministratorInformation Assurance ManagerECPA-1

Checks: C-37069r1_chk

Check the system for NFS mounts not using the "nosuid" option. Procedure: # mount -v | grep " type nfs " | egrep -v "nosuid" If the mounted file systems do not have the "nosuid" option, this is a finding.

Fix: F-32336r1_fix

Edit "/etc/fstab" and add the "nosuid" option for all NFS file systems. Remount the NFS file systems to make the change take effect.

b

The system must use an access control program.

CM-6 - Medium - CCI-000366 - V-940 - SV-37756r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN006580

Vuln IDs

V-940

Rule IDs

SV-37756r1_rule

Access control programs (such as TCP_WRAPPERS) provide the ability to enhance system security posture.System AdministratorEBRU-1

Checks: C-36953r1_chk

The tcp_wrappers package is provided with the RHEL distribution. Other access control programs may be available but will need to be checked manually. Determine if tcp_wrappers is installed. # rpm -qa | grep tcp_wrappers If no package is listed, this is a finding.

Fix: F-32218r1_fix

Install and configure the tcp_wrappers package.

b

The system's access control program must log each system access attempt.

AU-2 - Medium - CCI-000126 - V-941 - SV-37757r3_rule

RMF Control

AU-2

Severity

M

CCI

Version

GEN006600

Vuln IDs

V-941

Rule IDs

SV-37757r3_rule

If access attempts are not logged, then multiple attempts to log on to the system by an unauthorized user may go undetected.System Administrator

Checks: C-36954r3_chk

The tcp_wrappers package is provided with the RHEL distribution. Other access control programs may be available but will need to be checked manually. Depending on what system is used for log processing either /etc/syslog.conf or /etc/rsyslog.conf will be the logging configuration file. Normally, tcpd logs to the mail facility in "/etc/syslog.conf" or “/etc/rsyslog.conf”. Determine if syslog or rsyslog is configured to log events by tcpd. Procedure: # grep -E “(\*.info|\*.debug|authpriv.info|authpriv.debug|authpriv.\*)” /etc/syslog.conf | grep –v ‘#’ Or: # grep -E “(\*.info|\*.debug|authpriv.info|authpriv.debug|authpriv.\*)” /etc/rsyslog.conf | grep –v ‘#’ If no entries exist, this is a finding. If there are no “authpriv.info”, “authpriv.debug”, “authpriv.*” or “*.info” or “*.debug” not followed by “authpriv.none”, this is a finding. If an alternate access control program is used and it does not provide logging of access attempts, this is a finding.

Fix: F-32219r1_fix

Configure the access restriction program to log every access attempt. Ensure the implementation instructions for tcp_wrappers are followed so system access attempts are recorded to the system log files. If an alternate application is used, it must support this function.

b

Access to the cron utility must be controlled using the cron.allow and/or cron.deny file(s).

AC-6 - Medium - CCI-000225 - V-974 - SV-27320r2_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN002960

Vuln IDs

V-974

Rule IDs

SV-27320r2_rule

The cron facility allows users to execute recurring jobs on a regular and unattended basis. The cron.allow file designates accounts allowed to enter and execute jobs using the cron facility. If the cron.allow file is not present, users listed in the cron.deny file are not allowed to use the cron facility. Improper configuration of cron may open the facility up for abuse by system intruders and malicious users.System Administrator

Checks: C-28457r2_chk

This check is not applicable if only the root user is permitted to use cron. Check for the existence of the cron.allow and cron.deny files. # ls -lL /etc/cron.allow # ls -lL /etc/cron.deny If neither file exists, this is a finding.

Fix: F-24560r2_fix

Create /etc/cron.allow and/or /etc/cron.deny with appropriate content and reboot the system to ensure no lingering cron jobs are processed.

b

The cron.allow file must have mode 0600 or less permissive.

AC-6 - Medium - CCI-000225 - V-975 - SV-27326r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN002980

Vuln IDs

V-975

Rule IDs

SV-27326r1_rule

A readable and/or writable cron.allow file by users other than root could allow potential intruders and malicious users to use the file contents to help discern information, such as who is allowed to execute cron programs, which could be harmful to overall system and network security.System AdministratorECLP-1

Checks: C-28462r1_chk

Check mode of the cron.allow file. Procedure: # ls -lL /etc/cron.allow If the file has a mode more permissive than 0600, this is a finding.

Fix: F-24566r1_fix

Change the mode of the cron.allow file to 0600. Procedure: # chmod 0600 /etc/cron.allow

b

Cron must not execute group-writable or world-writable programs.

AC-6 - Medium - CCI-000225 - V-976 - SV-37384r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003000

Vuln IDs

V-976

Rule IDs

SV-37384r1_rule

If cron executes group-writable or world-writable programs, there is a possibility that unauthorized users could manipulate the programs with malicious intent. This could compromise system and network security.System AdministratorDCSL-1

Checks: C-36071r1_chk

List all cronjobs on the system. Procedure: # ls /var/spool/cron # ls /etc/cron.d /etc/crontab /etc/cron.daily /etc/cron.hourly /etc/cron.monthly /etc/cron.weekly or # ls /etc/cron*|grep -v deny If cron jobs exist under any of the above directories, use the following command to search for programs executed by cron: # more <cron job file> Perform a long listing of each program file found in the cron file to determine if the file is group-writable or world-writable. # ls -la <cron program file> If cron executes group-writable or world-writable files, this is a finding.

Fix: F-31315r1_fix

Remove the world-writable and group-writable permissions from the cron program file(s) identified. # chmod go-w <cron program file>

b

Cron must not execute programs in, or subordinate to, world-writable directories.

AC-6 - Medium - CCI-000225 - V-977 - SV-37388r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003020

Vuln IDs

V-977

Rule IDs

SV-37388r1_rule

If cron programs are located in or subordinate to world-writable directories, they become vulnerable to removal and replacement by malicious users or system intruders.System AdministratorDCSL-1

Checks: C-36074r1_chk

List all cronjobs on the system. Procedure: # ls /var/spool/cron # ls /etc/cron.d /etc/crontab /etc/cron.daily /etc/cron.hourly /etc/cron.monthly /etc/cron.weekly or # ls /etc/cron*|grep -v deny If cron jobs exist under any of the above directories, use the following command to search for programs executed by at: # more <cron job file> Perform a long listing of each directory containing program files found in the cron file to determine if the directory is world-writable. # ls -ld <cron program directory> If cron executes programs in world-writable directories, this is a finding.

Fix: F-31318r1_fix

Remove the world-writable permission from the cron program directories identified. Procedure: # chmod o-w <cron program directory>

b

Crontab files must have mode 0600 or less permissive, and files in cron script directories must have mode 0700 or less permissive.

AC-6 - Medium - CCI-000225 - V-978 - SV-37466r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003080

Vuln IDs

V-978

Rule IDs

SV-37466r1_rule

To protect the integrity of scheduled system jobs and prevent malicious modification to these jobs, crontab files must be secured.System AdministratorECLP-1

Checks: C-36132r1_chk

Check the mode of the crontab files. # ls -lL /var/spool/cron/ # ls -lL /etc/cron.d/ # ls -lL /etc/crontab If any crontab file has a mode more permissive than 0600, this is a finding.

Fix: F-31377r1_fix

Change the mode of the crontab files. # chmod 0600 /var/spool/cron/* /etc/cron.d/* /etc/crontab

b

Cron and crontab directories must have mode 0755 or less permissive.

AC-6 - Medium - CCI-000225 - V-979 - SV-37470r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003100

Vuln IDs

V-979

Rule IDs

SV-37470r1_rule

To protect the integrity of scheduled system jobs and to prevent malicious modification to these jobs, crontab files must be secured.System AdministratorECLP-1

Checks: C-36136r1_chk

Check the mode of the crontab directories. Procedure: # ls -ld /var/spool/cron # ls -ld /etc/cron.d /etc/crontab /etc/cron.daily /etc/cron.hourly /etc/cron.monthly /etc/cron.weekly or # ls -ld /etc/cron*|grep -v deny If the mode of any of the crontab directories is more permissive than 0755, this is a finding.

Fix: F-31381r1_fix

Change the mode of the crontab directories. # chmod 0755 <crontab directory>

b

Cron and crontab directories must be owned by root or bin.

AC-6 - Medium - CCI-000225 - V-980 - SV-37474r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003120

Vuln IDs

V-980

Rule IDs

SV-37474r1_rule

Incorrect ownership of the cron or crontab directories could permit unauthorized users the ability to alter cron jobs and run automated jobs as privileged users. Failure to give ownership of cron or crontab directories to root or to bin provides the designated owner and unauthorized users with the potential to access sensitive information or change the system configuration which could weaken the system's security posture.System AdministratorECLP-1

Checks: C-36140r1_chk

Check the owner of the crontab directories. Procedure: # ls -ld /var/spool/cron # ls -ld /etc/cron.d /etc/crontab /etc/cron.daily /etc/cron.hourly /etc/cron.monthly /etc/cron.weekly or # ls -ld /etc/cron*|grep -v deny If the owner of any of the crontab directories is not root or bin, this is a finding.

Fix: F-31386r1_fix

Change the mode of the crontab directories. # chown root <crontab directory>

b

Cron and crontab directories must be group-owned by root, sys, bin or cron.

AC-6 - Medium - CCI-000225 - V-981 - SV-37476r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003140

Vuln IDs

V-981

Rule IDs

SV-37476r1_rule

To protect the integrity of scheduled system jobs and to prevent malicious modification to these jobs, crontab files must be secured. Failure to give group-ownership of cron or crontab directories to a system group provides the designated group and unauthorized users with the potential to access sensitive information or change the system configuration which could weaken the system's security posture.System AdministratorECLP-1

Checks: C-36142r1_chk

Check the group owner of cron and crontab directories. Procedure: # ls -ld /var/spool/cron # ls -ld /etc/cron.d /etc/crontab /etc/cron.daily /etc/cron.hourly /etc/cron.monthly /etc/cron.weekly or # ls -ld /etc/cron*|grep -v deny If a directory is not group-owned by root, sys, bin, or cron, this is a finding.

Fix: F-31388r1_fix

Change the group owner of cron and crontab directories. # chgrp root <crontab directory>

b

Cron logging must be implemented.

AU-2 - Medium - CCI-000126 - V-982 - SV-27352r2_rule

RMF Control

AU-2

Severity

M

CCI

Version

GEN003160

Vuln IDs

V-982

Rule IDs

SV-27352r2_rule

Cron logging can be used to trace the successful or unsuccessful execution of cron jobs. It can also be used to spot intrusions into the use of the cron facility by unauthorized and malicious users. System Administrator

Checks: C-28494r2_chk

Depending on what system is used for log processing either /etc/syslog.conf or /etc/rsyslog.conf will be the logging configuration file. # grep cron /etc/syslog.conf Or: # grep cron /etc/rsyslog.conf If cron logging is not configured, this is a finding. Check the configured cron log file found in the cron entry of /etc/syslog.conf or /etc/rsyslog.conf (normally /var/log/cron). # ls -lL /var/log/cron If this file does not exist, or is older than the last cron job, this is a finding.

Fix: F-31389r2_fix

Edit /etc/syslog.conf or /etc/rsyslog.conf and setup cron logging

b

The cronlog file must have mode 0600 or less permissive.

AC-6 - Medium - CCI-000225 - V-983 - SV-27357r2_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003180

Vuln IDs

V-983

Rule IDs

SV-27357r2_rule

Cron logs contain reports of scheduled system activities and must be protected from unauthorized access or manipulation. System Administrator

Checks: C-28501r2_chk

Check the mode of the cron log file. Procedure: Depending on what system is used for log processing either /etc/syslog.conf or /etc/rsyslog.conf will be the logging configuration file. Check the configured cron log file found in the cron entry in /etc/syslog.conf or /etc/rsyslog.conf (normally /var/log/cron). # grep cron /etc/syslog.conf Or: # grep cron /etc/rsyslog.conf # ls -lL /var/log/cron If the mode is more permissive than 0600, this is a finding.

Fix: F-24602r1_fix

Change the mode of the cron log file. # chmod 0600 /var/log/cron

b

Access to the "at" utility must be controlled via the at.allow and/or at.deny file(s).

AC-6 - Medium - CCI-000225 - V-984 - SV-37512r2_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003280

Vuln IDs

V-984

Rule IDs

SV-37512r2_rule

The "at" facility selectively allows users to execute jobs at deferred times. It is usually used for one-time jobs. The at.allow file selectively allows access to the "at" facility. If there is no at.allow file, there is no ready documentation of who is allowed to submit "at" jobs.System Administrator

Checks: C-36168r2_chk

If the "at" package is not installed, this is not applicable. Check for the existence of at.allow and at.deny files. # ls -lL /etc/at.allow # ls -lL /etc/at.deny If neither file exists, this is a finding.

Fix: F-31419r1_fix

Create at.allow and/or at.deny files containing appropriate lists of users to be allowed or denied access to the "at" daemon.

b

The at.deny file must not be empty if it exists.

AC-6 - Medium - CCI-000225 - V-985 - SV-37516r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003300

Vuln IDs

V-985

Rule IDs

SV-37516r1_rule

On some systems, if there is no at.allow file and there is an empty at.deny file, then the system assumes everyone has permission to use the "at" facility. This could create an insecure setting in the case of malicious users or system intruders.trueInformation Assurance OfficerSystem AdministratorECLP-1

Checks: C-36175r1_chk

# more /etc/at.deny If the at.deny file exists and is empty, this is a finding.

Fix: F-31426r1_fix

Add appropriate users to the at.deny file, or remove the empty at.deny file if an at.allow file exists.

b

Default system accounts (with the exception of root) must not be listed in the at.allow file or must be included in the at.deny file if the at.allow file does not exist.

AC-6 - Medium - CCI-000225 - V-986 - SV-37517r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003320

Vuln IDs

V-986

Rule IDs

SV-37517r1_rule

Default accounts, such as bin, sys, adm, uucp, daemon, and others, should never have access to the "at" facility. This would create a possible vulnerability open to intruders or malicious users.System AdministratorECPA-1

Checks: C-36177r1_chk

# more /etc/at.allow If default accounts (such as bin, sys, adm, and others) are listed in the at.allow file, this is a finding.

Fix: F-31427r1_fix

Remove the default accounts (such as bin, sys, adm, and others, traditionally UID less than 500) from the at.allow file.

b

The at.allow file must have mode 0600 or less permissive.

AC-6 - Medium - CCI-000225 - V-987 - SV-37518r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003340

Vuln IDs

V-987

Rule IDs

SV-37518r1_rule

Permissions more permissive than 0600 (read, write and execute for the owner) may allow unauthorized or malicious access to the at.allow and/or at.deny files.System AdministratorECLP-1

Checks: C-36178r1_chk

Check the mode of the at.allow file. # ls -lL /etc/at.allow If the at.allow file has a mode more permissive than 0600, this is a finding.

Fix: F-31428r1_fix

Change the mode of the at.allow file. # chmod 0600 /etc/at.allow

b

The "at" daemon must not execute group-writable or world-writable programs.

AC-6 - Medium - CCI-000225 - V-988 - SV-37519r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003360

Vuln IDs

V-988

Rule IDs

SV-37519r1_rule

If the "at" facility executes world-writable or group-writable programs, it is possible for the programs to be accidentally or maliciously changed or replaced without the owner's intent or knowledge. This would cause a system security breach.System AdministratorDCSL-1

Checks: C-36179r1_chk

List the "at" jobs on the system. Procedure: # ls -la /var/spool/at For each "at" job file, determine which programs are executed. Procedure: # more <at job file> Check the each program executed by "at" for group- or world-writable permissions. Procedure: # ls -la <at program file> If "at" executes group or world-writable programs, this is a finding.

Fix: F-31429r1_fix

Remove group-write and world-write permissions from files executed by at jobs. Procedure: # chmod go-w <file>

b

The "at" daemon must not execute programs in, or subordinate to, world-writable directories.

AC-6 - Medium - CCI-000225 - V-989 - SV-37520r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003380

Vuln IDs

V-989

Rule IDs

SV-37520r1_rule

If "at" programs are located in, or subordinate, to world-writable directories, they become vulnerable to removal and replacement by malicious users or system intruders.System AdministratorDCSL-1

Checks: C-36180r1_chk

List any "at" jobs on the system. Procedure: # ls /var/spool/at For each "at" job, determine which programs are executed by "at." Procedure: # more <at job file> Check the directory containing each program executed by "at" for world-writable permissions. Procedure: # ls -la <at program file directory> If "at" executes programs in world-writable directories, this is a finding.

Fix: F-31432r1_fix

Remove the world-writable permission from directories containing programs executed by "at". Procedure: # chmod o-w <at program directory>

c

SNMP communities, users, and passphrases must be changed from the default.

IA-5 - High - CCI-000178 - V-993 - SV-37689r1_rule

RMF Control

IA-5

Severity

H

CCI

CCI-000178

Version

GEN005300

Vuln IDs

V-993

Rule IDs

SV-37689r1_rule

Whether active or not, default SNMP passwords, users, and passphrases must be changed to maintain security. If the service is running with the default authenticators, then anyone can gather data about the system and the network and use the information to potentially compromise the integrity of the system or network(s).System AdministratorIAAC-1

Checks: C-36883r1_chk

Check the SNMP configuration for default passwords. Procedure: Examine the default install location /etc/snmp/snmpd.conf or: # find / -name snmpd.conf # more <snmpd.conf file> Identify any community names or user password configuration. If any community name or password is set to a default value such as "public", "private", "snmp-trap", or "password", or any value which does not meet DISA password requirements, this is a finding.

Fix: F-31908r1_fix

Change the default passwords. To change them, locate the file snmpd.conf. Edit the file. Locate the line system-group-read-community which has a default password of "public" and make the password something more secure and less guessable. Do the same for the lines reading system-group-write-community, read-community, write-community, trap and trap-community. Read the information in the file carefully. The trap is defining who to send traps to, for instance, by default. It is not a password, but the name of a host.

b

The snmpd.conf file must have mode 0600 or less permissive.

AC-6 - Medium - CCI-000225 - V-994 - SV-37696r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN005320

Vuln IDs

V-994

Rule IDs

SV-37696r1_rule

The snmpd.conf file contains authenticators and must be protected from unauthorized access and modification.System AdministratorECLP-1

Checks: C-36892r1_chk

Check the mode of the SNMP daemon configuration file. Procedure: Examine the default install location /etc/snmp/snmpd.conf or: # find / -name snmpd.conf # ls -lL <snmpd.conf file> If the snmpd.conf file has a mode more permissive than 0600, this is a finding.

Fix: F-31997r1_fix

Change the mode of the SNMP daemon configuration file to 0600. Procedure: # chmod 0600 <snmpd.conf>

b

Management Information Base (MIB) files must have mode 0640 or less permissive.

AC-6 - Medium - CCI-000225 - V-995 - SV-37698r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN005340

Vuln IDs

V-995

Rule IDs

SV-37698r1_rule

The ability to read the MIB file could impart special knowledge to an intruder or malicious user about the ability to extract compromising information about the system or network.System AdministratorECLP-1

Checks: C-36893r1_chk

Check the modes for all Management Information Base (MIB) files on the system. Procedure: # find / -name *.mib # ls -lL <mib file> Any file returned with a mode 0640 or less permissive is a finding.

Fix: F-32000r1_fix

Change the mode of MIB files to 0640. Procedure: # chmod 0640 <mib file>

b

Public directories must be the only world-writable directories and world-writable files must be located only in public directories.

CM-6 - Medium - CCI-000366 - V-1010 - SV-37645r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN002480

Vuln IDs

V-1010

Rule IDs

SV-37645r1_rule

World-writable files and directories make it easy for a malicious user to place potentially compromising files on the system. The only authorized public directories are those temporary directories supplied with the system or those designed to be temporary file repositories. The setting is normally reserved for directories used by the system and by users for temporary file storage, (e.g., /tmp), and for directories requiring global read/write access.System AdministratorECSC-1

Checks: C-36841r1_chk

Check the system for world-writable files. Procedure: # find / -perm -2 -a $ -type d -o -type f $ -exec ls -ld {} \; If any world-writable files are located, except those required for system operation such as /tmp and /dev/null, this is a finding.

Fix: F-31679r1_fix

Remove or change the mode for any world-writable file on the system not required to be world-writable. Procedure: # chmod o-w <file> Document all changes

a

Inetd or xinetd logging/tracing must be enabled.

AU-3 - Low - CCI-000134 - V-1011 - SV-37439r1_rule

RMF Control

AU-3

Severity

L

CCI

CCI-000134

Version

GEN003800

Vuln IDs

V-1011

Rule IDs

SV-37439r1_rule

Inetd or xinetd logging and tracing allows the system administrators to observe the IP addresses connecting to their machines and what network services are being sought. This provides valuable information when trying to find the source of malicious users and potential malicious users.System AdministratorECSC-1

Checks: C-36111r1_chk

The /etc/xinetd.conf file and each file in the /etc/xinetd.d directory file should be examined for the following: Procedure: log_type = SYSLOG authpriv log_on_success = HOST PID USERID EXIT log_on_failure = HOST USERID If xinetd is running and logging is not enabled, this is a finding.

Fix: F-31357r1_fix

Edit each file in the /etc/xinetd.d directory and the /etc/xinetd.conf file to contain: log_type = SYSLOG authpriv log_on_success = HOST PID USERID EXIT log_on_failure = HOST USERID The /etc/xinetd.conf file contains default values that will hold true for all services unless individually modified in the service's xinetd.d file. To make the new settings effective, restart the xinetd service: # service xinetd restart

c

The system must be configured to only boot from the system boot device.

CM-6 - High - CCI-000366 - V-1013 - SV-37986r1_rule

RMF Control

CM-6

Severity

H

CCI

Version

GEN008600

Vuln IDs

V-1013

Rule IDs

SV-37986r1_rule

The ability to boot from removable media is the same as being able to boot into single user, or maintenance, mode without a password. This ability could allow a malicious user to boot the system and perform changes with the potential to compromise or damage the system. It could also allow the system to be used for malicious purposes by a malicious anonymous user.System AdministratorECSC-1

Checks: C-37289r1_chk

Determine if the system is configured to boot from devices other than the system startup media. If so, this is a finding.

Fix: F-32526r1_fix

Configure the system to only boot from system startup media. Procedure: On systems with a BIOS or system controller use the BIOS interface at startup to remove all but the proper boot device from the boot device list.

b

The X server must have the correct options enabled.

CM-6 - Medium - CCI-000366 - V-1021 - SV-37207r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN000000-LNX00360

Vuln IDs

V-1021

Rule IDs

SV-37207r1_rule

Without the correct options enabled, the Xwindows system would be less secure and there would be no screen timeout.System Administrator

Checks: C-35896r1_chk

Verify the options of the running Xwindows server are correct. Procedure: Get the running xserver information # ps -ef |grep X If the response contains /usr/bin/Xorg:0 /usr/bin/Xorg:0 -br -audit 0 -auth /var/gdm/:0.Xauth -nolisten tcp vt7 this is indicative of Xorg starting through gdm. This is the default on RHEL. Examine the Xorg line: If the "-auth" option is missing this would be a finding. If the "-audit" option is missing or not set to 4, this is a finding. If the "-s" option is missing or greater than 15, this is a finding. If the response to the grep contains X:0 /usr/bin/X:0 this indicates the X server was started with the xinit command with no associated .xserverrc in the home directory of the user. No options are selected by default. This is a finding. Otherwise if there are options on the X:0 line: If the "-auth" option is missing this is a finding If the "-audit" option is missing or not set to 4, this is a finding. If the "-s" option is missing or greater than 15, this is a finding.

Fix: F-31154r1_fix

Enable the following options: -audit (at level 4), -auth and -s with 15 minutes as the timeout value. Procedure for gdm: Edit /etc/gdm/custom.conf and add the following: [server-Standard] name=Standard server command=/usr/bin/Xorg -br -audit 4 -s 15 chooser=false handled=true flexible=true priority=0 Procedure for xinit: Edit or create a .xserverrc file in the users home directory containing the startup script for xinit. This script must have an exec line with at least these options: exec /usr/bin/X -audit 4 -s 15 -auth <Xauth file> & The <Xauth file> is created using the "xauth" command and is customarily located in the users home directory with the name ".Xauthority".

b

An X server must have none of the following options enabled: -ac, -core (except for debugging purposes), or -nolock.

CM-6 - Medium - CCI-000366 - V-1022 - SV-37217r2_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN000000-LNX00380

Vuln IDs

V-1022

Rule IDs

SV-37217r2_rule

These options will detract from the security of the Xwindows system.System Administrator

Checks: C-35904r2_chk

If the "xorg-x11-server-Xorg" package is not installed, this is not applicable. Verify the options of the running Xwindows server are correct. Procedure: Get the running xserver information # ps -ef |grep X If the response contains /usr/bin/Xorg:0 /usr/bin/Xorg:0 -br -audit 0 -auth /var/gdm/:0.Xauth -nolisten tcp vt7 this is indicative of Xorg starting through gdm. This is the default window manager on RHEL. If the "-ac" option is found, this is a finding. If the "-core" option is found, this is a finding. If the "-nolock" option is found, this is a finding. If the response to the grep contains X:0 /usr/bin/X:0 Examine the X:0 line: If the "-ac" option is found, this is a finding. If the "-core" option is found, this is a finding. If the "-nolock" option is found, this is a finding.

Fix: F-31162r1_fix

Disable the unwanted options: Procedure: For gdm: Remove the -ac, -core and -nolock options by creating a "command" entry in the /etc/gdm/custom.conf file with the options removed. For Xwindows started by xinit: Create or modify the .xserverrc script in the users home directory to remove the -ac, -core and -nolock options from the exec /usr/bin/X command.

b

The system must not run an Internet Network News (INN) server.

CM-7 - Medium - CCI-000381 - V-1023 - SV-37899r1_rule

RMF Control

CM-7

Severity

M

CCI

CCI-000381

Version

GEN006240

Vuln IDs

V-1023

Rule IDs

SV-37899r1_rule

INN servers access Usenet newsfeeds and store newsgroup articles. INN servers use the Network News Transfer Protocol (NNTP) to transfer information from the Usenet to the server and from the server to authorized remote hosts. If this function is necessary to support a valid mission requirement, its use must be authorized and approved in the system accreditation package.System AdministratorInformation Assurance OfficerECSC-1

Checks: C-37125r1_chk

# ps -ef | egrep "innd|nntpd" If an Internet Network News server is running, this is a finding.

Fix: F-32393r1_fix

Disable the INN server.

b

The /etc/access.conf file must be owned by root.

AC-6 - Medium - CCI-000225 - V-1025 - SV-37224r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN000000-LNX00400

Vuln IDs

V-1025

Rule IDs

SV-37224r1_rule

The /etc/access.conf file contains entries restricting access from the system console by authorized System Administrators. If the file is owned by a user other than root, it could compromise the system.System AdministratorECLP-1

Checks: C-35912r1_chk

Check access configuration ownership: # ls -lL /etc/security/access.conf If this file exists and is not owned by root, this is a finding.

Fix: F-31171r1_fix

Follow the correct configuration parameters for access configuration file. Use the chown command to configure it properly. (for example: # chown root /etc/security/access.conf ).

b

The Samba Web Administration Tool (SWAT) must be restricted to the local host or require SSL.

AC-17 - Medium - CCI-001436 - V-1026 - SV-37870r1_rule

RMF Control

AC-17

Severity

M

CCI

Version

GEN006080

Vuln IDs

V-1026

Rule IDs

SV-37870r1_rule

SWAT is a tool used to configure Samba. It modifies Samba configuration, which can impact system security, and must be protected from unauthorized access. SWAT authentication may involve the root password, which must be protected by encryption when traversing the network. Restricting access to the local host allows for the use of SSH TCP forwarding, if configured, or administration by a web browser on the local system.System AdministratorEBRP-1

Checks: C-37085r3_chk

SWAT is a tool for configuring Samba and should only be found on a system with a requirement for Samba. If SWAT is used, it must be utilized with SSL to ensure a secure connection between the client and the server. Procedure: # grep -H "bin/swat" /etc/xinetd.d/*|cut -d: -f1 |xargs grep "only_from" If the value of the "only_from" line in the "xinetd.d" file which starts "/usr/sbin/swat" is not "localhost" or the equivalent, this is a finding.

Fix: F-32357r2_fix

Disable SWAT or require SWAT is only accessed via SSH. Procedure: If SWAT is not needed for operation of the system remove the SWAT package: # rpm -qa|grep swat Remove "samba-swat" or "samba3x-swat" depending on which one is installed # rpm --erase samba-swat or # rpm --erase samba3x-swat If SWAT is required but not at all times disable it when it is not needed. Modify the /etc/xinetd.d file for "swat" to contain a "disable = yes" line. To access using SSH: Follow vendor configuration documentation to create an stunnel for SWAT.

b

The /etc/smb.conf file must be owned by root.

AC-6 - Medium - CCI-000225 - V-1027 - SV-37871r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN006100

Vuln IDs

V-1027

Rule IDs

SV-37871r1_rule

The /etc/smb.conf file allows access to other machines on the network and grants permissions to certain users. If it is owned by another user, the file may be maliciously modified and the Samba configuration could be compromised.System AdministratorECLP-1

Checks: C-37087r1_chk

Check the ownership of the /etc/samba/smb.conf file. Procedure: # ls -l /etc/samba/smb.conf If an smb.conf file is not owned by root, this is a finding.

Fix: F-32360r1_fix

Change the ownership of the smb.conf file. Procedure: # chown root smb.conf

b

The /etc/smb.conf file must have mode 0644 or less permissive.

AC-6 - Medium - CCI-000225 - V-1028 - SV-37875r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN006140

Vuln IDs

V-1028

Rule IDs

SV-37875r1_rule

If the "smb.conf" file has excessive permissions, the file may be maliciously modified and the Samba configuration could be compromised.System AdministratorECLP-1

Checks: C-37094r1_chk

Check the mode of the smb.conf file. Procedure: # ls -lL /etc/samba/smb.conf If the "smb.conf" has a mode more permissive than 0644, this is a finding.

Fix: F-32370r1_fix

Change the mode of the smb.conf file to 0644 or less permissive. Procedure: # chmod 0644 smb.conf.

b

The /etc/smbpasswd file must be owned by root.

AC-6 - Medium - CCI-000225 - V-1029 - SV-37879r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN006160

Vuln IDs

V-1029

Rule IDs

SV-37879r1_rule

If the "smbpasswd" file is not owned by root, it may be maliciously accessed or modified, potentially resulting in the compromise of Samba accounts.System AdministratorECLP-1

Checks: C-37105r1_chk

Check the ownership of the "smbpasswd" file. # ls -l /etc/samba/passdb.tdb /etc/samba/secrets.tdb If the "smbpasswd" file is not owned by root, this is a finding.

Fix: F-32373r1_fix

Use the chown command to configure the files maintained by smbpasswd. For instance: # chown root /etc/samba/passdb.tdb /etc/samba/secrets.tdb

b

The smb.conf file must use the "hosts" option to restrict access to Samba.

AC-6 - Medium - CCI-000225 - V-1030 - SV-37887r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN006220

Vuln IDs

V-1030

Rule IDs

SV-37887r1_rule

Samba increases the attack surface of the system and must be restricted to communicate only with systems requiring access.System AdministratorECSC-1

Checks: C-37113r1_chk

Examine the "smb.conf" file. # more /etc/samba/smb.conf If the "hosts" option is not present to restrict access to a list of authorized hosts and networks, this is a finding.

Fix: F-32381r1_fix

Edit the "/etc/samba/smb.conf" file and set the "hosts" option to permit only authorized hosts to access Samba.

b

Users must not be able to change passwords more than once every 24 hours.

IA-5 - Medium - CCI-000198 - V-1032 - SV-37239r1_rule

RMF Control

IA-5

Severity

M

CCI

CCI-000198

Version

GEN000540

Vuln IDs

V-1032

Rule IDs

SV-37239r1_rule

The ability to change passwords frequently facilitates users reusing the same password. This can result in users effectively never changing their passwords. This would be accomplished by users changing their passwords when required and then immediately changing it to the original value. System AdministratorECSC-1

Checks: C-35931r1_chk

Check the minimum time period between password changes for each user account is 1 day. # cat /etc/shadow | cut -d ':' -f 4 | grep -v 1 If any results are returned, this is a finding.

Fix: F-31186r1_fix

Change the minimum time period between password changes for each user account to 1 day. # passwd -n 1 <user name>

c

Root passwords must never be passed over a network in clear text form.

IA-5 - High - CCI-000197 - V-1046 - SV-37150r2_rule

RMF Control

IA-5

Severity

H

CCI

CCI-000197

Version

GEN001100

Vuln IDs

V-1046

Rule IDs

SV-37150r2_rule

If a user accesses the root account (or any account) using an unencrypted connection, the password is passed over the network in clear text form and is subject to interception and misuse. This is true even if recommended procedures are followed by logging on to a named account and using the su command to access root.System Administrator

Checks: C-35865r2_chk

Determine if root has logged in over an unencrypted network connection. Examine /etc/syslog.conf to confirm the location to which "authpriv" messages are being sent. # grep authpriv.* /etc/syslog.conf Once the file is determined, perform the following command: # grep password <file> | more Look for any lines that do not have sshd as the associated service. If root has logged in over the network and sshd is not running, this is a finding.

Fix: F-31120r1_fix

Enable SSH on the system and use it for all remote connections used to attain root access

b

The system must not permit root logins using remote access programs such as ssh.

IA-2 - Medium - CCI-000770 - V-1047 - SV-37156r1_rule

RMF Control

IA-2

Severity

M

CCI

Version

GEN001120

Vuln IDs

V-1047

Rule IDs

SV-37156r1_rule

Even though communications are encrypted, an additional layer of security may be gained by extending the policy of not logging directly on as root. In addition, logging in with a user-specific account preserves the audit trail.System AdministratorECPA-1

Checks: C-35864r1_chk

Determine if the SSH daemon is configured to permit root logins. Procedure: # grep -v "^#" /etc/ssh/sshd_config | grep -i permitrootlogin If the PermitRootLogin entry is not found or is not set to "no", this is a finding.

Fix: F-31118r1_fix

Edit the sshd_config file and set the PermitRootLogin option to "no".

b

Audio devices must have mode 0660 or less permissive.

AC-6 - Medium - CCI-000225 - V-1048 - SV-37566r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN002320

Vuln IDs

V-1048

Rule IDs

SV-37566r1_rule

Audio and video devices that are globally accessible have proven to be another security hazard. There is software that can activate system microphones and video devices connected to user workstations and/or X terminals. Once the microphone has been activated, it is possible to eavesdrop on otherwise private conversations without the victim being aware of it. This action effectively changes the user's microphone into a bugging device.System AdministratorECLP-1

Checks: C-36215r1_chk

Check the mode of audio devices. # ls -lL /dev/audio* /dev/snd/* If the mode of audio devices are more permissive than 660, this is a finding.

Fix: F-31476r1_fix

Change the mode of audio devices. # chmod 0660 <audio device>

b

Audio devices must be owned by root.

AC-6 - Medium - CCI-000225 - V-1049 - SV-37575r2_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN002340

Vuln IDs

V-1049

Rule IDs

SV-37575r2_rule

Audio and video devices globally accessible have proven to be another security hazard. There is software that can activate system microphones and video devices connected to user workstations and/or X terminals. Once the microphone has been activated, it is possible to eavesdrop on otherwise private conversations without the victim being aware of it. This action effectively changes the user's microphone into a bugging device.System Administrator

Checks: C-36393r1_chk

Check the owner of audio devices. # ls -lL /dev/audio* /dev/snd/* If the owner of any audio device file is not root, this is a finding.

Fix: F-31611r2_fix

Edit the /etc/security/console.perms.d/50-default.perms file and comment the following line: <console> 0600 <sound> 0660 root.audio

b

The /etc/access.conf file must have a privileged group owner.

AC-6 - Medium - CCI-000225 - V-1054 - SV-37227r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN000000-LNX00420

Vuln IDs

V-1054

Rule IDs

SV-37227r1_rule

Depending on the access restrictions of the /etc/access.conf file, if the group owner were not a privileged group, it could endanger system security.System AdministratorECLP-1

Checks: C-35917r1_chk

Check access configuration group ownership: # ls -lL /etc/security/access.conf If this file exists and has a group-owner that is not a privileged user, this is a finding.

Fix: F-31174r1_fix

Use the chgrp command to ensure the group owner is root, sys, or bin. (for example: # chgrp root /etc/security/access.conf ).

b

The /etc/security/access.conf file must have mode 0640 or less permissive.

AC-6 - Medium - CCI-000225 - V-1055 - SV-37243r2_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN000000-LNX00440

Vuln IDs

V-1055

Rule IDs

SV-37243r2_rule

If the access permissions are more permissive than 0640, system security could be compromised.System Administrator

Checks: C-35930r1_chk

Check access configuration mode: # ls -lL /etc/security/access.conf If this file exists and has a mode more permissive than 0640, this is a finding.

Fix: F-31190r1_fix

Use the chmod command to set the permissions to 0640. (for example: # chmod 0640 /etc/security/access.conf ).

b

The /etc/smb.conf file must be group-owned by root, bin, sys, or system.

AC-6 - Medium - CCI-000225 - V-1056 - SV-37873r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN006120

Vuln IDs

V-1056

Rule IDs

SV-37873r1_rule

If the group owner of the "smb.conf" file is not root or a system group, the file may be maliciously modified and the Samba configuration could be compromised.System AdministratorECLP-1

Checks: C-37089r1_chk

Check the group ownership of the "smb.conf" file. Procedure: # ls -lL /etc/samba/smb.conf If the "smb.conf" file is not group-owned by root, bin, sys, or system, this is a finding.

Fix: F-32365r1_fix

Change the group owner of the smb.conf file. Procedure: # chgrp root smb.conf

b

The smbpasswd file must be group-owned by root.

AC-6 - Medium - CCI-000225 - V-1058 - SV-41574r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN006180

Vuln IDs

V-1058

Rule IDs

SV-41574r1_rule

If the smbpasswd file is not group-owned by root, the smbpasswd file may be maliciously accessed or modified, potentially resulting in the compromise of Samba accounts.System AdministratorECLP-1

Checks: C-40075r1_chk

Check "smbpasswd" ownership: # ls -lL /etc/samba/passdb.tdb /etc/samba/secrets.tdb If the "smbpasswd" file is not group-owned by root, this is a finding.

Fix: F-35231r1_fix

Use the chgrp command to ensure that the group owner of the smbpasswd file is root. For instance: # chgrp root /etc/samba/passdb.tdb /etc/samba/secrets.tdb

b

The smbpasswd file must have mode 0600 or less permissive.

AC-6 - Medium - CCI-000225 - V-1059 - SV-41575r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN006200

Vuln IDs

V-1059

Rule IDs

SV-41575r1_rule

If the smbpasswd file has a mode more permissive than 0600, the smbpasswd file may be maliciously accessed or modified, potentially resulting in the compromise of Samba accounts.System AdministratorECLP-1

Checks: C-40077r1_chk

Check the mode of files maintained using "smbpasswd". Procedure: # ls -lL /etc/samba/passdb.tdb /etc/samba/secrets.tdb If a "smbpasswd" maintained file has a mode more permissive than 0600, this is a finding.

Fix: F-35233r1_fix

Change the mode of the files maintained through smbpasswd to 0600. Procedure: # chmod 0600 /etc/samba/passdb.tdb /etc/samba/secrets.tdb

b

Audio devices must be group-owned by root, sys, bin, or system.

AC-6 - Medium - CCI-000225 - V-1061 - SV-37577r2_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN002360

Vuln IDs

V-1061

Rule IDs

SV-37577r2_rule

Without privileged group owners, audio devices will be vulnerable to being used as eaves-dropping devices by malicious users or intruders to possibly listen to conversations containing sensitive information.System Administrator

Checks: C-36404r2_chk

Check the group-owner of audio devices. Procedure: # ls -lL /dev/audio* /dev/snd/* If the group-owner of an audio device is not root, sys, bin, system, or audio this is a finding.

Fix: F-31613r2_fix

Change the group-owner of the audio device. Procedure: # chgrp <root, sys, bin, system, audio> <audio device>

a

The root shell must be located in the / file system.

CM-6 - Low - CCI-000366 - V-1062 - SV-37380r1_rule

RMF Control

CM-6

Severity

L

CCI

Version

GEN001080

Vuln IDs

V-1062

Rule IDs

SV-37380r1_rule

To ensure the root shell is available in repair and administrative modes, the root shell must be located in the / file system.System AdministratorECSC-1

Checks: C-36067r2_chk

Determine if root's shell executable resides on a dedicated file system. Procedure: Find the location of the root user's shell # grep "^root" /etc/passwd|cut -d: -f7|cut -d/ -f2 The result is the top level directory under / where the shell resides (e.g., usr) Check if it is on a dedicated file system. # grep /<top level directory> /etc/fstab If /<top level directory> is on a dedicated file system, this is a finding.

Fix: F-31311r1_fix

Change the root account's shell to one present on the / file system. Procedure: Edit /etc/passwd and change the shell for the root account to one present on the / file system (such as /bin/sh, assuming /bin is not on a separate file system). If the system does not store shell configuration in the /etc/passwd file, consult vendor documentation for the correct procedure for the system.

b

Graphical desktop environments provided by the system must automatically lock after 15 minutes of inactivity and the system must require users to re-authenticate to unlock the environment. Applications requiring continuous, real-time screen display (i.e., network management products) require the following and need to be documented with the IAO. -The logon session does not have administrator rights. -The display station (i.e., keyboard, monitor, etc.) is located in a controlled access area.

AC-11 - Medium - CCI-000057 - V-4083 - SV-48455r1_rule

RMF Control

AC-11

Severity

M

CCI

CCI-000057

Version

GEN000500

Vuln IDs

V-4083

Rule IDs

SV-48455r1_rule

If graphical desktop sessions do not lock the session after 15 minutes of inactivity, requiring re-authentication to resume operations, the system or individual data could be compromised by an alert intruder who could exploit the oversight. This requirement applies to graphical desktop environments provided by the system to locally attached displays and input devices as well as to graphical desktop environments provided to remote systems, including thin clients.System Administrator

Checks: C-45121r1_chk

If the "xorg-x11-server-Xorg" package is not installed, this is not applicable. For the Gnome screen saver, check the idle_activation_enabled flag. Procedure: # gconftool-2 --direct --config-source xml:readwrite:/etc/gconf/gconf.xml.mandatory --get /apps/gnome-screensaver/idle_activation_enabled If this does not return "true" and a documented exception has not been made by the IAO, this is a finding.

Fix: F-26907r1_fix

For the Gnome screen saver, set the idle_activation_enabled flag. Procedure: # gconftool-2 --direct --config-source xml:readwrite:/etc/gconf/gconf.xml.mandatory --type bool --set /apps/gnome-screensaver/idle_activation_enabled true

b

The system must prohibit the reuse of passwords within five iterations.

IA-5 - Medium - CCI-000200 - V-4084 - SV-37323r3_rule

RMF Control

IA-5

Severity

M

CCI

CCI-000200

Version

GEN000800

Vuln IDs

V-4084

Rule IDs

SV-37323r3_rule

If a user, or root, used the same password continuously or was allowed to change it back shortly after being forced to change it to something else, it would provide a potential intruder with the opportunity to keep guessing at one user's password until it was guessed correctly.System Administrator

Checks: C-36015r4_chk

# ls /etc/security/opasswd If /etc/security/opasswd does not exist, then this is a finding. # grep password /etc/pam.d/system-auth| egrep '(pam_pwhistory.so|pam_unix.so|pam_cracklib.so)' | grep remember If the "remember" option in /etc/pam.d/system-auth is not 5 or greater, this is a finding. Check for system-auth-ac inclusions. # grep -c system-auth-ac /etc/pam.d/* If the system-auth-ac file is included anywhere # more /etc/pam.d/system-auth-ac | grep password | egrep '(pam_pwhistory.so|pam_unix.so|pam_cracklib.so)' | grep remember If in /etc/pam.d/system-auth-ac is referenced by another file and the "remember" option is not set to 5 or greater this is a finding.

Fix: F-31265r2_fix

Create the password history file. # touch /etc/security/opasswd # chown root:root /etc/security/opasswd # chmod 0600 /etc/security/opasswd Enable password history. If /etc/pam.d/system-auth references /etc/pam.d/system-auth-ac refer to the man page for system-auth-ac for a description of how to add options not configurable with authconfig. Edit /etc/pam.d/system-auth to include the remember option on any "password pam_unix" or "password pam_history" lines set to at least 5.

b

User start-up files must not execute world-writable programs.

AC-6 - Medium - CCI-000225 - V-4087 - SV-37433r3_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001940

Vuln IDs

V-4087

Rule IDs

SV-37433r3_rule

If start-up files execute world-writable programs, especially in unprotected directories, they could be maliciously modified to become trojans that destroy user files or otherwise compromise the system at the user, or higher, level. If the system is compromised at the user level, it is much easier to eventually compromise the system at the root and network level.System Administrator

Checks: C-36012r7_chk

Determine the world writable files on the system (Note: ignore all files under /proc): # find / -perm -002 -a -type f -exec ls -ld {} \; | <more or redirect the output to a file> # find / -perm -002 -a -type d -exec ls -ld {} \; | <more or redirect the output to a file> View the password file to determine where the home directories for users are: # more /etc/passwd Once the directory for the human users is determined, grep for the lists of world writable files and directories within the users’ home directories. An example would be: # grep /opt/app/bin/daemon /home/*/.* where /home is the directory for the human users on the system and /opt/app/bin/daemon is a world writable file.

Fix: F-31263r2_fix

Remove the world-writable permission of files referenced by local initialization scripts, or remove the references to these files in the local initialization scripts.

b

All system start-up files must be owned by root.

AC-6 - Medium - CCI-000225 - V-4089 - SV-37264r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001660

Vuln IDs

V-4089

Rule IDs

SV-37264r1_rule

System start-up files not owned by root could lead to system compromise by allowing malicious users or applications to modify them for unauthorized purposes. This could lead to system and network compromise.System AdministratorECLP-1

Checks: C-35954r1_chk

Check run control scripts' ownership. # ls -lL /etc/rc* /etc/init.d Alternatively: # find /etc -name "[SK][0-9]*"|xargs stat -L -c %U:%n If any run control script is not owned by root or bin, this is a finding.

Fix: F-31210r1_fix

Change the ownership of the run control script(s) with incorrect ownership. # find /etc -name "[SK][0-9]*"|xargs stat -L -c %U:%n|egrep -v "^root:"|cut -d: -f2|xargs chown root

b

All system start-up files must be group-owned by root, sys, bin, other, or system.

AC-6 - Medium - CCI-000225 - V-4090 - SV-37269r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001680

Vuln IDs

V-4090

Rule IDs

SV-37269r1_rule

If system start-up files do not have a group owner of root or a system group, the files may be modified by malicious users or intruders.System AdministratorECLP-1

Checks: C-35960r1_chk

Check run control scripts' group ownership. Procedure: # ls -lL /etc/rc* /etc/init.d Alternatively: # find /etc -name "[SK][0-9]*"|xargs stat -L -c %G:%n|egrep -v "^(root|sys|bin|other):" If any run control script is not group-owned by root, sys, bin, or other system groups, this is a finding.

Fix: F-31216r1_fix

b

System start-up files must only execute programs owned by a privileged UID or an application.

AC-6 - Medium - CCI-000225 - V-4091 - SV-37270r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001700

Vuln IDs

V-4091

Rule IDs

SV-37270r1_rule

System start-up files executing programs owned by other than root (or another privileged user) or an application indicating the system may have been compromised.System AdministratorDCSL-1

Checks: C-35962r1_chk

Determine the programs executed by system start-up files. Determine the ownership of the executed programs. # cat /etc/rc*/* /etc/init.d/* | more # ls -l <executed program> Alternatively: # for FILE in `egrep -r "/" /etc/rc.* /etc/init.d|awk '/^.*[^\/][0-9A-Za-z_\/]*/{print $2}'|egrep "^/"|sort|uniq`;do if [ -e $FILE ]; then stat -L -c '%U:%n' $FILE;fi;done This provides a list of files referenced by initialization scripts and their associated UIDs. If any file is run by an initialization file and is not owned by root, sys, bin, or in rare cases, an application account, this is a finding.

Fix: F-31218r1_fix

Change the ownership of the file executed from system startup scripts to root, bin, sys, or other. # chown root <executed file>

b

System BIOS or system controllers supporting password protection must have administrator accounts/passwords configured, and no others.

AC-3 - Medium - CCI-000213 - V-4246 - SV-37925r1_rule

RMF Control

AC-3

Severity

M

CCI

Version

GEN008620

Vuln IDs

V-4246

Rule IDs

SV-37925r1_rule

A system's BIOS or system controller handles the initial startup of a system and its configuration must be protected from unauthorized modification. When the BIOS or system controller supports the creation of user accounts or passwords, such protections must be used and accounts/passwords only assigned to system administrators. Failure to protect BIOS or system controller settings could result in Denial of Service or compromise of the system resulting from unauthorized configuration changes.System AdministratorECSC-1

Checks: C-37163r1_chk

On systems with a BIOS or system controller, verify a supervisor or administrator password is set. If a password is not set, this is a finding. If the BIOS or system controller supports user-level access in addition to supervisor/administrator access, determine if this access is enabled. If so, this is a finding.

Fix: F-4157r2_fix

Access the system's BIOS or system controller. Set a supervisor/administrator password if one has not been set. Disable a user-level password if one has been set.

c

The system must not use removable media as the boot loader.

CM-6 - High - CCI-000366 - V-4247 - SV-41534r1_rule

RMF Control

CM-6

Severity

H

CCI

Version

GEN008640

Vuln IDs

V-4247

Rule IDs

SV-41534r1_rule

Malicious users with removable boot media can gain access to a system configured to use removable media as the boot loader.System AdministratorECSC-1

Checks: C-2057r2_chk

Ask the SA if the system uses removable media for the boot loader. If it does, this is a finding.

Fix: F-4158r2_fix

Configure the system to use a bootloader installed on fixed media.

c

For systems capable of using GRUB, the system must be configured with GRUB as the default boot loader unless another boot loader has been authorized, justified, and documented using site-defined procedures.

CM-6 - High - CCI-000366 - V-4248 - SV-42186r1_rule

RMF Control

CM-6

Severity

H

CCI

Version

GEN008660

Vuln IDs

V-4248

Rule IDs

SV-42186r1_rule

GRUB is a versatile boot loader used by several platforms that can provide authentication for access to the system or boot loader.System AdministratorECAR-1, ECAR-2, ECAR-3

Checks: C-40580r1_chk

Determine if the system uses the GRUB boot loader; # ls -l /boot/grub/grub.conf If no grub.conf file exists, and the bootloader on the system has not been authorized, justified, and documented, this is a finding.

Fix: F-35823r1_fix

Configure the system to use the GRUB bootloader or document, justify, and authorize the alternate bootloader.

c

The system boot loader must require authentication.

AC-3 - High - CCI-000213 - V-4249 - SV-37933r1_rule

RMF Control

AC-3

Severity

H

CCI

Version

GEN008700

Vuln IDs

V-4249

Rule IDs

SV-37933r1_rule

If the system's boot loader does not require authentication, users with console access to the system may be able to alter the system boot configuration or boot the system into single user or maintenance mode, which could result in Denial of Service or unauthorized privileged access to the system.System AdministratorIAIA-1, IAIA-2

Checks: C-37191r1_chk

Check the "/boot/grub/grub.conf" or "/boot/grub/menu.lst" files. # more /boot/grub/menu.lst Check for a password configuration line, such as: password --md5 <password-hash> This line should be just below the line beginning with "timeout". Please note <password-hash> will be replaced by the actual MD5 encrypted password. If the password line is not in either of the files, this is a finding. For any bootloader other than GRUB which has been authorized, justified and documented for use on the system refer to the vendor documentation on password support. If the bootloader does not support encrypted passwords, this is a finding.

Fix: F-32425r1_fix

The GRUB console boot loader can be configured to use an MD5 encrypted password by adding password --md5 password-hash to the "/boot/grub/grub.conf" file. Use "/sbin/grub-md5-crypt" to generate MD5 passwords from the command line.

b

The system's boot loader configuration file(s) must have mode 0600 or less permissive.

AC-6 - Medium - CCI-000225 - V-4250 - SV-37942r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN008720

Vuln IDs

V-4250

Rule IDs

SV-37942r1_rule

File permissions greater than 0600 on boot loader configuration files could allow an unauthorized user to view or modify sensitive information pertaining to system boot instructions.System AdministratorECLP-1

Checks: C-37221r2_chk

Check /boot/grub/grub.conf permissions: # ls -lL /boot/grub/grub.conf If /boot/grub/grub.conf has a mode more permissive than 0600, then this is a finding. For any bootloader other than GRUB which has been authorized, justified and documented for use on the system refer to the vendor documentation for the location of the configuration file. If the bootloader configuration file has a mode more permissive than 0600, this is a finding.

Fix: F-32433r1_fix

Change the mode of the grub.conf file to 0600. # chmod 0600 /boot/grub/grub.conf

c

If the system boots from removable media, it must be stored in a safe or similarly secured container.

SC-32 - High - CCI-001208 - V-4255 - SV-4255r2_rule

RMF Control

SC-32

Severity

H

CCI

Version

GEN008680

Vuln IDs

V-4255

Rule IDs

SV-4255r2_rule

Storing the boot loader on removable media in an insecure location could allow a malicious user to modify the systems boot instructions or boot to an insecure operating system.System AdministratorInformation Assurance OfficerPESS-1

Checks: C-2079r2_chk

Ask the SA if the system boots from removable media. If so, ask if the boot media is stored in a secure container when not in use. If it is not, this is a finding.

Fix: F-4166r2_fix

Store the system boot media in a secure container when not in use.

c

The system must not have special privilege accounts, such as shutdown and halt.

AC-6 - High - CCI-000225 - V-4268 - SV-37181r1_rule

RMF Control

AC-6

Severity

H

CCI

Version

GEN000000-LNX00320

Vuln IDs

V-4268

Rule IDs

SV-37181r1_rule

If special privilege accounts are compromised, the accounts could provide privileges to execute malicious commands on a system.System AdministratorIAAC-1

Checks: C-35884r1_chk

Perform the following to check for unnecessary privileged accounts: # grep "^shutdown" /etc/passwd # grep "^halt" /etc/passwd # grep "^reboot" /etc/passwd If any unnecessary privileged accounts exist this is a finding.

Fix: F-31139r1_fix

Remove any special privilege accounts, such as shutdown and halt, from the /etc/passwd and /etc/shadow files using the "userdel" or "system-config-users" commands.

b

The system must not have unnecessary accounts.

AC-2 - Medium - CCI-000012 - V-4269 - SV-38176r1_rule

RMF Control

AC-2

Severity

M

CCI

Version

GEN000290

Vuln IDs

V-4269

Rule IDs

SV-38176r1_rule

Accounts providing no operational purpose provide additional opportunities for system compromise. Unnecessary accounts include user accounts for individuals not requiring access to the system and application accounts for applications not installed on the system.System AdministratorIAAC-1

Checks: C-37560r2_chk

Check the system for unnecessary user accounts. Procedure: # more /etc/passwd Obtain a list of authorized accounts from the IAO. If any unnecessary accounts are found on the system, this is a finding.

Fix: F-32804r1_fix

Remove all unnecessary accounts from the /etc/passwd file before connecting a system to the network. Other accounts that are associated with a service not in use should also be removed.

b

The /etc/news/incoming.conf (or equivalent) must have mode 0600 or less permissive.

AC-6 - Medium - CCI-000225 - V-4273 - SV-37901r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN006260

Vuln IDs

V-4273

Rule IDs

SV-37901r1_rule

Excessive permissions on the "incoming.conf" file may allow unauthorized modification which could lead to Denial-of-Service to authorized users or provide access to unauthorized users.System AdministratorECLP-1

Checks: C-37127r1_chk

RHEL uses the InternetNewsDaemon (innd) news server. The file corresponding to "/etc/news/hosts.nntp" is "/etc/news/incoming.conf". Check the permissions for "/etc/news/incoming.conf". # ls -lL /etc/news/incoming.conf If "/etc/news/incoming.conf" has a mode more permissive than 0600, this is a finding.

Fix: F-32395r1_fix

Change the mode of the "/etc/news/incoming.conf" file to 0600. # chmod 0600 /etc/news/incoming.conf

b

The /etc/news/infeed.conf (or equivalent) must have mode 0600 or less permissive.

AC-6 - Medium - CCI-000225 - V-4274 - SV-37712r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN006280

Vuln IDs

V-4274

Rule IDs

SV-37712r1_rule

Excessive permissions on the "" file may allow unauthorized modification which could lead to Denial of Service to authorized users or provide access to unauthorized users.System AdministratorECLP-1

Checks: C-36913r1_chk

RHEL uses the InternetNewsDaemon (innd) news server. The file that corresponds to "/etc/news/hosts.nntp.nolimit" is "/etc/news/infeed.conf". Check the permissions for "/etc/news/infeed.conf". # ls -lL /etc/news/infeed.conf If "/etc/news/infeed.conf" has a mode more permissive than 0600, this is a finding.

Fix: F-32122r1_fix

Change the mode of "/etc/news/infeed.conf" to 0600. # chmod 0600 /etc/news/infeed.conf

b

The /etc/news/readers.conf (or equivalent) must have mode 0600 or less permissive.

AC-6 - Medium - CCI-000225 - V-4275 - SV-37714r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN006300

Vuln IDs

V-4275

Rule IDs

SV-37714r1_rule

Excessive permissions on the readers.conf file may allow unauthorized modification which could lead to Denial of Service to authorized users or provide access to unauthorized users.System AdministratorECLP-1

Checks: C-36918r1_chk

Check the permissions for "/etc/news/readers.conf". # ls -lL /etc/news/readers.conf If /etc/news/readers.conf has a mode more permissive than 0600, this is a finding.

Fix: F-32155r1_fix

Change the mode of the /etc/news/readers.conf file to 0600. # chmod 0600 /etc/news/readers.conf

b

The /etc/news/passwd.nntp file (or equivalent) must have mode 0600 or less permissive.

AC-6 - Medium - CCI-000225 - V-4276 - SV-37731r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN006320

Vuln IDs

V-4276

Rule IDs

SV-37731r1_rule

File permissions more permissive than 0600 for "/etc/news/passwd.nntp" may allow access to privileged information by system intruders or malicious users.System AdministratorECLP-1

Checks: C-36928r1_chk

Check "/etc/news/passwd.nntp" permissions: # ls -lL /etc/news/passwd.nntp If "/etc/news/passwd.nntp" has a mode more permissive than 0600, this is a finding.

Fix: F-32193r1_fix

Change the mode of the "/etc/news/passwd.nntp" file. # chmod 0600 /etc/news/passwd.nntp

b

Files in /etc/news must be owned by root or news.

AC-6 - Medium - CCI-000225 - V-4277 - SV-37735r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN006340

Vuln IDs

V-4277

Rule IDs

SV-37735r1_rule

If critical system files are not owned by a privileged user, system integrity could be compromised.System AdministratorECLP-1

Checks: C-36931r1_chk

Check the ownership of the files in "/etc/news". Procedure: # ls -al /etc/news If any files are not owned by root or news, this is a finding.

Fix: F-32195r1_fix

Change the ownership of the files in "/etc/news" to root or news. Procedure: # chown root /etc/news/*

b

The files in /etc/news must be group-owned by root or news.

AC-6 - Medium - CCI-000225 - V-4278 - SV-37737r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN006360

Vuln IDs

V-4278

Rule IDs

SV-37737r1_rule

If critical system files do not have a privileged group-owner, system integrity could be compromised.System AdministratorECLP-1

Checks: C-36933r1_chk

Check "/etc/news" files group ownership: Procedure: # ls -al /etc/news If "/etc/news" files are not group-owned by root or news, this is a finding.

Fix: F-32198r1_fix

Change the group-owner of the files in "/etc/news" to root or news. Procedure: # chgrp root /etc/news/*

c

The SSH daemon must be configured to only use the SSHv2 protocol.

AC-17 - High - CCI-001436 - V-4295 - SV-37818r2_rule

RMF Control

AC-17

Severity

H

CCI

Version

GEN005500

Vuln IDs

V-4295

Rule IDs

SV-37818r2_rule

SSHv1 is not a DoD-approved protocol and has many well-known vulnerability exploits. Exploits of the SSH daemon could provide immediate root access to the system.System Administrator

Checks: C-37020r1_chk

Locate the sshd_config file: # more /etc/ssh/sshd_config Examine the file. If the variables 'Protocol 2,1' or 'Protocol 1' are defined on a line without a leading comment, this is a finding. If the SSH server is F-Secure, the variable name for SSH 1 compatibility is 'Ssh1Compatibility', not 'protocol'. If the variable 'Ssh1Compatiblity' is set to 'yes', then this is a finding.

Fix: F-32288r2_fix

Edit the sshd_config file and set the "Protocol" setting to "2". If using the F-Secure SSH server, set the "Ssh1Compatibility" setting to "no". Restart the SSH daemon. # /sbin/service sshd restart

b

Remote consoles must be disabled or protected from unauthorized access.

AC-17 - Medium - CCI-000070 - V-4298 - SV-37376r1_rule

RMF Control

AC-17

Severity

M

CCI

CCI-000070

Version

GEN001000

Vuln IDs

V-4298

Rule IDs

SV-37376r1_rule

The remote console feature provides an additional means of access to the system which could allow unauthorized access if not disabled or properly secured. With virtualization technologies, remote console access is essential as there is no physical console for virtual machines. Remote console access must be protected in the same manner as any other remote privileged access method.System AdministratorECSC-1

Checks: C-36063r1_chk

Check /etc/securetty # more /etc/securetty If the file does not exist, or contains more than "console" or a single "tty" device this is a finding.

Fix: F-31307r1_fix

Create if needed and set the contents of /etc/securetty to a "console" or "tty" device. # echo console > /etc/securetty or # echo tty1 > /etc/securetty

b

The system clock must be synchronized to an authoritative DoD time source.

AU-8 - Medium - CCI-001492 - V-4301 - SV-37402r1_rule

RMF Control

AU-8

Severity

M

CCI

CCI-001492

Version

GEN000240

Vuln IDs

V-4301

Rule IDs

SV-37402r1_rule

To assure the accuracy of the system clock, it must be synchronized with an authoritative time source within DoD. Many system functions, including time-based login and activity restrictions, automated reports, system logs, and audit records depend on an accurate system clock. If there is no confidence in the correctness of the system clock, time-based functions may not operate as intended and records may be of diminished value. Authoritative time sources include authorized time servers within the enclave that synchronize with upstream authoritative sources. Specific requirements for the upstream synchronization of network time protocol (NTP) servers are covered in the Network Other Devices STIG. For systems located on isolated or closed networks, it is not necessary to synchronize with a global authoritative time source. If a global authoritative time source is not available to systems on an isolated network, a local authoritative time source must be established on this network and used by the systems connected to this network. This is necessary to provide the ability to correlate events and allow for the correct operation of time-dependent protocols between systems on the isolated network. If the system is completely isolated (i.e., it has no connections to networks or other systems), time synchronization is not required as no correlation of events between systems will be necessary. If the system is completely isolated, this requirement is not applicable.System AdministratorECSC-1

Checks: C-36085r1_chk

Check if NTP running: # ps -ef | egrep "xntpd|ntpd" Check if "ntpd -qg" scheduled to run: # grep "ntpd -qg" /var/spool/cron/* # grep "ntpd -qg" /etc/cron.d/* # grep "ntpd -qg" /etc/cron.daily/* # grep "ntpd -qg" /etc/cron.hourly/* # grep "ntpd -qg" /etc/cron.monthly/* # grep "ntpd -qg" /etc/cron.weekly/* If NTP is running or "ntpd -qg" is found: # more /etc/ntp.conf Confirm the timeservers and peers or multicast client (as applicable) are local or authoritative U.S. DoD sources appropriate for the level of classification which the network operates. If a non-local/non-authoritative time-server is used, this is a finding.

Fix: F-31332r2_fix

Use an authoritative local time server or a time server operated by the U.S. government. Ensure all systems in the facility feed from one or more local time servers which feed from the authoritative U.S. government time server.

b

The root file system must employ journaling or another mechanism ensuring file system consistency.

CP-10 - Medium - CCI-000553 - V-4304 - SV-37398r1_rule

RMF Control

CP-10

Severity

M

CCI

CCI-000553

Version

GEN003640

Vuln IDs

V-4304

Rule IDs

SV-37398r1_rule

File system journaling, or logging, can allow reconstruction of file system data after a system crash, preserving the integrity of data that may have otherwise been lost. Journaling file systems typically do not require consistency checks upon booting after a crash, which can improve system availability. Some file systems employ other mechanisms to ensure consistency also satisfying this requirement.System AdministratorECAR-1, ECAR-2, ECAR-3

Checks: C-36083r1_chk

Logging should be enabled for those types of file systems not turning on logging by default. Procedure: # mount JFS, VXFS, HFS, XFS, reiserfs, EXT3 and EXT4 all turn logging on by default and will not be a finding. The ZFS file system uses other mechanisms to provide for file system consistency, and will not be a finding. For other file systems types, if the root file system does not support journaling this is a finding. If the 'nolog' option is set on the root file system that does support journaling, this is a finding.

Fix: F-31330r1_fix

Implement file system journaling for the root file system, or use a file system with other mechanisms to ensure file system consistency. If the root file system supports journaling, enable it. If the file system does not support journaling or another mechanism to ensure file system consistency, a migration to a different file system will be necessary.

b

The system must not run Samba unless needed.

AC-17 - Medium - CCI-001436 - V-4321 - SV-37867r1_rule

RMF Control

AC-17

Severity

M

CCI

Version

GEN006060

Vuln IDs

V-4321

Rule IDs

SV-37867r1_rule

Samba is a tool used for the sharing of files and printers between Windows and UNIX operating systems. It provides access to sensitive files and, therefore, poses a security risk if compromised.System AdministratorECSC-1

Checks: C-37082r1_chk

Check the system for a running Samba server. Procedure: # ps -ef |grep smbd If the Samba server is running, ask the SA if the Samba server is operationally required. If it is not, this is a finding.

Fix: F-32354r1_fix

If there is no functional need for Samba and the daemon is running, disable the daemon by killing the process ID as noted from the output of ps -ef |grep smbd. The samba package should also be removed or not installed if there is no functional requirement. Procedure: rpm -qa |grep samba This will show whether "samba" or "samba3x" is installed. To remove: rpm --erase samba or rpm --erase samba3x

b

The /etc/sysctl.conf file must be owned by root.

AC-6 - Medium - CCI-000225 - V-4334 - SV-37253r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN000000-LNX00480

Vuln IDs

V-4334

Rule IDs

SV-37253r1_rule

The sysctl.conf file specifies the values for kernel parameters to be set on boot. These settings can affect the system's security.System AdministratorECLP-1

Checks: C-35944r1_chk

Check /etc/sysctl.conf ownership. # ls -lL /etc/sysctl.conf If /etc/sysctl.conf is not owned by root, this is a finding.

Fix: F-31200r1_fix

Use the chown command to change the owner of /etc/sysctl.conf to root: # chown root /etc/sysctl.conf

b

The /etc/sysctl.conf file must be group-owned by root.

AC-6 - Medium - CCI-000225 - V-4335 - SV-37257r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN000000-LNX00500

Vuln IDs

V-4335

Rule IDs

SV-37257r1_rule

The sysctl.conf file specifies the values for kernel parameters to be set on boot. These settings can affect the system's security.System AdministratorECLP-1

Checks: C-35947r1_chk

Check /etc/sysctl.conf group ownership: # ls -lL /etc/sysctl.conf If /etc/sysctl.conf is not group-owned by root, this is a finding.

Fix: F-31203r1_fix

Use the chgrp command to change the group owner of /etc/sysctl.conf to root: # chgrp root /etc/sysctl.conf

b

The /etc/sysctl.conf file must have mode 0600 or less permissive.

AC-6 - Medium - CCI-000225 - V-4336 - SV-37258r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN000000-LNX00520

Vuln IDs

V-4336

Rule IDs

SV-37258r1_rule

The sysctl.conf file specifies the values for kernel parameters to be set on boot. These settings can affect the system's security.System AdministratorECLP-1

Checks: C-35948r1_chk

Check /etc/sysctl.conf permissions: # ls -lL /etc/sysctl.conf If /etc/sysctl.conf has a mode more permissive than 0600, this is a finding.

Fix: F-31204r1_fix

Use the chmod command to change the mode of the /etc/sysctl.conf file. # chmod 0600 /etc/sysctl.conf

c

The Linux NFS Server must not have the insecure file locking option.

AC-6 - High - CCI-000225 - V-4339 - SV-37316r1_rule

RMF Control

AC-6

Severity

H

CCI

Version

GEN000000-LNX00560

Vuln IDs

V-4339

Rule IDs

SV-37316r1_rule

Insecure file locking could allow for sensitive data to be viewed or edited by an unauthorized user.System AdministratorIAIA-1, IAIA-2

Checks: C-36008r1_chk

Determine if an NFS server is running on the system by: # ps -ef |grep nfsd If an NFS server is running, confirm it is not configured with the insecure_locks option by: # exportfs -v The example below would be a finding: /misc/export speedy.example.com(rw,insecure_locks)

Fix: F-4250r3_fix

Remove the "insecure_locks" option from all NFS exports on the system. Procedure: Edit /etc/exports and remove all instances of the insecure_locks option. Re-export the file systems to make the setting take effect. # exportfs -a

c

The x86 CTRL-ALT-DELETE key sequence must be disabled.

CM-6 - High - CCI-000366 - V-4342 - SV-37327r1_rule

RMF Control

CM-6

Severity

H

CCI

Version

GEN000000-LNX00580

Vuln IDs

V-4342

Rule IDs

SV-37327r1_rule

Undesirable reboots can occur if the CTRL-ALT-DELETE key sequence is not disabled. Such reboots may cause a loss of data or loss of access to critical information.System AdministratorECSC-1

Checks: C-36030r2_chk

Verify that reboot using the CTRL-ALT-DELETE key sequence has been disabled by performing: # grep ctrlaltdel /etc/inittab If the line returned does not specify "/usr/bin/logger", or is not commented out, this is a finding.

Fix: F-31276r1_fix

Ensure the CTRL-ALT-DELETE key sequence has been disabled and attempts to use the sequence are logged. In the /etc/inittab file replace: ca::ctrlaltdel:/sbin/shutdown -t3 -r now with ca:nil:ctrlaltdel:/usr/bin/logger -p security.info "Ctrl-Alt-Del was pressed"

b

The Linux PAM system must not grant sole access to admin privileges to the first user who logs into the console.

AC-6 - Medium - CCI-000225 - V-4346 - SV-37339r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN000000-LNX00600

Vuln IDs

V-4346

Rule IDs

SV-37339r1_rule

If an unauthorized user has been granted privileged access while logged in at the console, the security posture of a system could be greatly compromised. Additionally, such a situation could deny legitimate root access from another terminal.System AdministratorECPA-1

Checks: C-2225r2_chk

Ensure the pam_console.so module is not configured in any files in /etc/pam.d by: # cd /etc/pam.d # grep pam_console.so * Or # ls -la /etc/security/console.perms If either the pam_console.so entry or the file /etc/security/console.perms is found then this is a finding.

Fix: F-4257r3_fix

Configure PAM to not grant sole access of administrative privileges to the first user logged in at the console. Identify any instances of pam_console. # cd /etc/pam.d # grep pam_console.so * For any files containing an un-commented reference to pam_console.so, edit the file and remove or comment out the reference. Remove the console.perms file if it exists: # rm /etc/security/console.perms

b

Audit logs must be rotated daily.

CM-6 - Medium - CCI-000366 - V-4357 - SV-37945r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN002860

Vuln IDs

V-4357

Rule IDs

SV-37945r1_rule

Rotate audit logs daily to preserve audit file system space and to conform to the DoD/DISA requirement. If it is not rotated daily and moved to another location, then there is more of a chance for the compromise of audit data by malicious users.System AdministratorECSC-1

Checks: C-37230r1_chk

Check for any crontab entries that rotate audit logs. Procedure: # crontab -l If such a cron job is found, this is not a finding. Otherwise, query the SA. If there is a process automatically rotating audit logs, this is not a finding. If the SA manually rotates audit logs, this is a finding, because if the SA is not there, it will not be accomplished. If the audit output is not archived daily, to tape or disk, this is a finding. This can be ascertained by looking at the audit log directory and, if more than one file is there, or if the file does not have today's date, this is a finding.

Fix: F-32436r1_fix

Configure a cron job or other automated process to rotate the audit logs on a daily basis.

b

The cron.deny file must have mode 0600 or less permissive.

AC-6 - Medium - CCI-000225 - V-4358 - SV-27362r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003200

Vuln IDs

V-4358

Rule IDs

SV-27362r1_rule

If file permissions for cron.deny are more permissive than 0600, sensitive information could be viewed or edited by unauthorized users. System AdministratorECLP-1

Checks: C-28506r1_chk

Check the mode of the cron.deny file. # ls -lL /etc/cron.deny If the cron.deny file does not exist this is not a finding. If the cron.deny file exists and the mode is more permissive than 0600, this is a finding.

Fix: F-24608r1_fix

Change the mode of the cron.deny file. # chmod 0600 /etc/cron.deny

a

Cron programs must not set the umask to a value less restrictive than 077.

AC-6 - Low - CCI-000225 - V-4360 - SV-37489r1_rule

RMF Control

AC-6

Severity

L

CCI

Version

GEN003220

Vuln IDs

V-4360

Rule IDs

SV-37489r1_rule

The umask controls the default access mode assigned to newly created files. A umask of 077 limits new files to mode 700 or less permissive. Although umask is often represented as a 4-digit octal number, the first digit representing special access modes is typically ignored or required to be 0.trueIf a cron program sets the umask to 000 or does not restrict the world-writable permission, this becomes a CAT I finding.System AdministratorECCD-1, ECCD-2

Checks: C-36148r1_chk

Determine if there are any crontabs by viewing a long listing of the directory. If there are crontabs, examine them to determine what cron jobs exist. Check for any programs specifying an umask more permissive than 077: Procedure: # ls -lL /var/spool/cron # ls -lL /etc/cron.d /etc/cron.daily /etc/cron.hourly /etc/cron.monthly /etc/cron.weekly or # ls -lL /etc/cron.*|grep -v deny # cat <crontab file> # grep umask <cron program> If there are no cron jobs present, this vulnerability is not applicable. If any cron job contains an umask more permissive than 077, this is a finding.

Fix: F-31397r1_fix

Edit cron script files and modify the umask to 077.

b

The cron.allow file must be owned by root, bin, or sys.

AC-6 - Medium - CCI-000225 - V-4361 - SV-27369r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003240

Vuln IDs

V-4361

Rule IDs

SV-27369r1_rule

If the owner of the cron.allow file is not set to root, bin, or sys, the possibility exists for an unauthorized user to view or to edit sensitive information.System AdministratorECLP-1

Checks: C-28513r1_chk

# ls -lL /etc/cron.allow If the cron.allow file is not owned by root, sys, or bin, this is a finding.

Fix: F-24614r1_fix

# chown root /etc/cron.allow

b

The "at" directory must have mode 0755 or less permissive.

AC-6 - Medium - CCI-000225 - V-4364 - SV-37521r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003400

Vuln IDs

V-4364

Rule IDs

SV-37521r1_rule

If the "at" directory has a mode more permissive than 0755, unauthorized users could be allowed to view or to edit files containing sensitive information within the "at" directory. Unauthorized modifications could result in Denial of Service to authorized "at" jobs.System AdministratorECLP-1

Checks: C-36181r1_chk

Check the mode of the "at" directory. Procedure: # ls -ld /var/spool/at If the directory mode is more permissive than 0755, this is a finding.

Fix: F-31433r1_fix

Change the mode of the "at" directory to 0755. Procedure: # chmod 0755 <at directory>

b

The at directory must be owned by root, bin, sys, daemon, or cron.

AC-6 - Medium - CCI-000225 - V-4365 - SV-37527r2_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003420

Vuln IDs

V-4365

Rule IDs

SV-37527r2_rule

If the owner of the "at" directory is not root, bin, or sys, unauthorized users could be allowed to view or edit files containing sensitive information within the directory.System Administrator

Checks: C-36186r2_chk

Check the ownership of the "at" directory: Procedure: # ls -ld /var/spool/at If the directory is not owned by root, sys, bin, daemon, or cron, this is a finding.

Fix: F-31441r1_fix

Change the owner of the "at" directory to root, bin, sys, or system. Procedure: # chown <root or other system account> <"at" directory>

b

"At" jobs must not set the umask to a value less restrictive than 077.

AC-6 - Medium - CCI-000225 - V-4366 - SV-37531r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003440

Vuln IDs

V-4366

Rule IDs

SV-37531r1_rule

The umask controls the default access mode assigned to newly created files. A umask of 077 limits new files to mode 700 or less permissive. Although umask is often represented as a 4-digit number, the first digit representing special access modes is typically ignored or required to be 0.trueSystem AdministratorInformation Assurance OfficerECCD-1, ECCD-2

Checks: C-36190r1_chk

Determine what "at" jobs exist on the system. Procedure: # ls /var/spool/at If there are no "at" jobs present, this is not applicable. Determine if any of the "at" jobs or any scripts referenced execute the "umask" command. Check for any umask setting more permissive than 077. # grep umask <at job or referenced script> If any "at" job or referenced script sets umask to a value more permissive than 077, this is a finding.

Fix: F-31445r1_fix

Edit "at" jobs or referenced scripts to remove "umask" commands that set umask to a value less restrictive than 077.

b

The at.allow file must be owned by root, bin, or sys.

AC-6 - Medium - CCI-000225 - V-4367 - SV-37533r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003460

Vuln IDs

V-4367

Rule IDs

SV-37533r1_rule

If the owner of the at.allow file is not set to root, bin, or sys, unauthorized users could be allowed to view or edit sensitive information contained within the file.System AdministratorECLP-1

Checks: C-36192r1_chk

# ls -lL /etc/at.allow If the at.allow file is not owned by root, sys, or bin, this is a finding.

Fix: F-31448r1_fix

Change the owner of the at.allow file. # chown root /etc/at.allow

b

The at.deny file must be owned by root, bin, or sys.

AC-6 - Medium - CCI-000225 - V-4368 - SV-37535r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003480

Vuln IDs

V-4368

Rule IDs

SV-37535r1_rule

If the owner of the at.deny file is not set to root, bin, or sys, unauthorized users could be allowed to view or edit sensitive information contained within the file.System AdministratorECLP-1

Checks: C-36194r1_chk

# ls -lL /etc/at.deny If the at.deny file is not owned by root, sys, or bin, this is a finding.

Fix: F-31451r1_fix

Change the owner of the at.deny file. # chown root /etc/at.deny

b

The traceroute command owner must be root.

AC-6 - Medium - CCI-000225 - V-4369 - SV-37463r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003960

Vuln IDs

V-4369

Rule IDs

SV-37463r1_rule

If the traceroute command owner has not been set to root, an unauthorized user could use this command to obtain knowledge of the network topology inside the firewall. This information may allow an attacker to determine trusted routers and other network information potentially leading to system and network compromise.System AdministratorECLP-1

Checks: C-36129r1_chk

# ls -lL /bin/traceroute If the traceroute command is not owned by root, this is a finding.

Fix: F-31373r1_fix

Change the owner of the traceroute command to root. Example: # chown root /bin/traceroute

b

The traceroute command must be group-owned by sys, bin, root, or system.

AC-6 - Medium - CCI-000225 - V-4370 - SV-37464r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003980

Vuln IDs

V-4370

Rule IDs

SV-37464r1_rule

If the group owner of the traceroute command has not been set to a system group, unauthorized users could have access to the command and use it to gain information regarding a network's topology inside of the firewall. This information may allow an attacker to determine trusted routers and other network information potentially leading to system and network compromise.System AdministratorECLP-1

Checks: C-36130r1_chk

Check the group ownership of the traceroute file. Procedure: # ls -lL /bin/traceroute If the traceroute command is not group-owned by root, sys, bin, or system, this is a finding.

Fix: F-31375r1_fix

Change the group-owner of the traceroute command to root. Procedure: # chgrp root /bin/traceroute

b

The traceroute file must have mode 0700 or less permissive.

AC-6 - Medium - CCI-000225 - V-4371 - SV-37465r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN004000

Vuln IDs

V-4371

Rule IDs

SV-37465r1_rule

If the mode of the traceroute executable is more permissive than 0700, malicious code could be inserted by an attacker and triggered whenever the traceroute command is executed by authorized users. Additionally, if an unauthorized user is granted executable permissions to the traceroute command, it could be used to gain information about the network topology behind the firewall. This information may allow an attacker to determine trusted routers and other network information potentially leading to system and network compromise.System AdministratorECLP-1

Checks: C-36131r1_chk

# ls -lL /bin/traceroute If the traceroute command has a mode more permissive than 0700, this is a finding.

Fix: F-31376r1_fix

Change the mode of the traceroute command. # chmod 0700 /bin/traceroute

c

Administrative accounts must not run a web browser, except as needed for local service administration.

AC-6 - High - CCI-000225 - V-4382 - SV-37469r2_rule

RMF Control

AC-6

Severity

H

CCI

Version

GEN004220

Vuln IDs

V-4382

Rule IDs

SV-37469r2_rule

If a web browser flaw is exploited while running as a privileged user, the entire system could be compromised. Specific exceptions for local service administration should be documented in site-defined policy. These exceptions may include HTTP(S)-based tools used for the administration of the local system, services, or attached devices. Examples of possible exceptions are HP's System Management Homepage (SMH), the CUPS administrative interface, and Sun's StorageTek Common Array Manager (CAM) when these services are running on the local system.System Administrator

Checks: C-36135r3_chk

Look in the root account home directory for a .mozilla directory. If none exists, this is not a finding. If there is one, verify with the root users and the IAO the intent of the browsing. If the browsing is not limited to authorized local services administration, this is a finding.

Fix: F-31380r1_fix

Enforce policy requiring administrative accounts use web browsers only for local service administration.

a

The SMTP service's SMTP greeting must not provide version information.

CM-6 - Low - CCI-000366 - V-4384 - SV-37505r2_rule

RMF Control

CM-6

Severity

L

CCI

Version

GEN004560

Vuln IDs

V-4384

Rule IDs

SV-37505r2_rule

The version of the SMTP service can be used by attackers to plan an attack based on vulnerabilities present in the specific version.System Administrator

Checks: C-36163r1_chk

To check for the version of either sendmail or Postfix being displayed in the greeting: # telnet localhost 25 If a version number is displayed, this is a finding.

Fix: F-31414r2_fix

Ensure sendmail or Postfix has been configured to mask the version information. Procedure for sendmail: Edit the /etc/mail/sendmail.mc file to mask the veresion number by editing the line with "dnl" as follows: define(`confSMTP_LOGIN_MSG', ` Mail Server Ready ; $b')dnl rebuild the sendmail.cf file. for Postfix: Examine the "smtpd_banner" line of /etc/postfix/main.conf and remove any "$mail_version" entry on it or comment the entire "smtpd_banner" line to use the default value which does not display the version information.

b

The system must not use .forward files.

CM-6 - Medium - CCI-000366 - V-4385 - SV-37506r3_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN004580

Vuln IDs

V-4385

Rule IDs

SV-37506r3_rule

The .forward file allows users to automatically forward mail to another system. Use of .forward files could allow the unauthorized forwarding of mail and could potentially create mail loops which could degrade system performance.System Administrator

Checks: C-36165r2_chk

Check forwarding capability from sendmail. Procedure: grep "O ForwardPath" /etc/mail/sendmail.cf If the entry contains a file path, this is a finding. Search for any .forward in users home directories on the system by: # for pwline in `cut -d: -f1,6 /etc/passwd`; do homedir=`echo ${pwline}|cut -d: -f2`;username=`echo ${pwline} | cut -d: -f1`;echo $username `stat -c %n $homedir/.forward 2>null`; done|egrep "\.forward" If any users have a .forward file in their home directory, this is a finding.

Fix: F-31416r3_fix

Disable forwarding for sendmail and remove .forward files from the system Procedure: Edit the /etc/mail/sendmail.mc file to change the ForwardPath entry to a null path by adding the line define(`confFORWARD_PATH',`') rebuild the sendmail.cf file. If the /etc/mail/sendmail.mc file does not exist, the sendmail.cf file should be updated directly. Remove all .forward files on the system # find / -name .forward -delete

c

Anonymous FTP accounts must not have a functional shell.

AC-6 - High - CCI-000225 - V-4387 - SV-37549r2_rule

RMF Control

AC-6

Severity

H

CCI

Version

GEN005000

Vuln IDs

V-4387

Rule IDs

SV-37549r2_rule

If an anonymous FTP account has been configured to use a functional shell, attackers could gain access to the shell if the account is compromised.System Administrator

Checks: C-36203r2_chk

Check the shell for the anonymous FTP account. Procedure: # cat /etc/passwd | grep -i "^ftp:" | awk -F":" '{print$7}' If the seventh field is empty (the entry ends with a ':') or if the seventh field does not contain one of the following, this is a finding: /bin/false /dev/null /usr/bin/false /bin/true /sbin/nologin

Fix: F-31462r1_fix

Configure anonymous FTP accounts to use a non-functional shell. If necessary, edit the /etc/passwd file to remove any functioning shells associated with the ftp account and replace them with non-functioning shells, such as /dev/null.

b

If the system is a Network Management System (NMS) server, it must only run the NMS and any software required by the NMS.

SC-32 - Medium - CCI-001208 - V-4392 - SV-37708r1_rule

RMF Control

SC-32

Severity

M

CCI

Version

GEN005380

Vuln IDs

V-4392

Rule IDs

SV-37708r1_rule

Installing extraneous software on a system designated as a dedicated Network Management System (NMS) server poses a security threat to the system and the network. Should an attacker gain access to the NMS through unauthorized software, the entire network may be susceptible to malicious activity.System AdministratorDCPA-1

Checks: C-36903r1_chk

Ask the SA if this is an NMS server. If it is an NMS server, then ask what other applications run on it. If there is anything other than network management software and DBMS software used only for the storage and inquiry of NMS data, this is a finding.

Fix: F-32073r1_fix

Ensure only authorized software is loaded on a designated NMS server. Authorized software is limited to the NMS software itself, a database management system for the NMS server if necessary, and network management software.

b

The /etc/syslog.conf file must be owned by root.

AC-6 - Medium - CCI-000225 - V-4393 - SV-37707r2_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN005400

Vuln IDs

V-4393

Rule IDs

SV-37707r2_rule

If the /etc/syslog.conf file is not owned by root, unauthorized users could be allowed to view, edit, or delete important system messages handled by the syslog facility.System Administrator

Checks: C-36904r2_chk

Check /etc/syslog.conf or /etc/rsyslog.conf ownership: For syslog: # ls -lL /etc/syslog.conf For rsyslog: # ls -lL /etc/rsyslog.conf If /etc/syslog.conf or /etc/rsyslog.conf is not owned by root, this is a finding.

Fix: F-32061r2_fix

Use the chown command to set the owner to root. # chown root /etc/syslog.conf Or: # chown root /etc/rsyslog.conf

b

The /etc/syslog.conf file must be group-owned by root, bin, sys, or system.

AC-6 - Medium - CCI-000225 - V-4394 - SV-37711r2_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN005420

Vuln IDs

V-4394

Rule IDs

SV-37711r2_rule

If the group owner of /etc/syslog.conf is not root, bin, or sys, unauthorized users could be permitted to view, edit, or delete important system messages handled by the syslog facility.System Administrator

Checks: C-36910r2_chk

Check /etc/syslog.conf or /etc/rsyslog.conf group ownership. Procedure: # ls -lL /etc/syslog.conf Or: # ls -lL /etc/syslog.conf If /etc/syslog.conf or /etc/rsyslog.conf is not group owned by root, sys, bin, or system, this is a finding.

Fix: F-32088r2_fix

Procedure: # chgrp root /etc/syslog.conf Or # chgrp root /etc/rsyslog.conf

b

The system must only use remote syslog servers (log hosts) that is justified and documented using site-defined procedures.

CM-6 - Medium - CCI-000366 - V-4395 - SV-37812r2_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN005460

Vuln IDs

V-4395

Rule IDs

SV-37812r2_rule

If a remote log host is in use and it has not been justified and documented with the IAO, sensitive information could be obtained by unauthorized users without the SA's knowledge. A remote log host is any host to which the system is sending syslog messages over a network.trueInformation Assurance OfficerSystem Administrator

Checks: C-37014r2_chk

Examine the syslog.conf or rsyslog.conf file for any references to remote log hosts. # grep -v "^#" /etc/syslog.conf | grep '@' Or: # grep -v "^#" /etc/rsyslog.conf | grep '@' Destination locations beginning with an '@' represent log hosts. If the log host name is a local alias such as "loghost", consult the /etc/hosts or other name databases as necessary to obtain the canonical name or address for the log host. Determine if the host referenced is a log host documented using site-defined procedures. If an undocumented log host is referenced, this is a finding.

Fix: F-32281r1_fix

Remove or document the referenced undocumented log host.

b

The system must be configured with a default gateway for IPv4 if the system uses IPv4, unless the system is a router.

CM-6 - Medium - CCI-000366 - V-4397 - SV-37918r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN005560

Vuln IDs

V-4397

Rule IDs

SV-37918r1_rule

If a system has no default gateway defined, the system is at increased risk of man-in-the-middle, monitoring, and Denial of Service attacks.System AdministratorECSC-1

Checks: C-37145r1_chk

Check the system for an IPv4 default route. If the system is a VM host and acts as a router solely for the benefit of its client systems, then this rule is not applicable. Procedure: # netstat -r |grep default If a default route is not defined, this is a finding.

Fix: F-32410r1_fix

Set a default gateway for IPv4.

b

A system used for routing must not run other network services or applications.

SC-32 - Medium - CCI-001208 - V-4398 - SV-37924r2_rule

RMF Control

SC-32

Severity

M

CCI

Version

GEN005580

Vuln IDs

V-4398

Rule IDs

SV-37924r2_rule

Installing extraneous software on a system designated as a dedicated router poses a security threat to the system and the network. Should an attacker gain access to the router through the unauthorized software, the entire network is susceptible to malicious activity.System Administrator

Checks: C-37160r2_chk

If the system is a VM host and acts as a router solely for the benefit of its client systems, then this rule is not applicable. Check to see if the system is a router: # chkconfig --list | grep :on | egrep '(ospf|route|bgp|zebra|quagga)' If the system is running a routing service, it is a router. If it is not, this is not applicable. Check the system for non-routing network services. Procedure: # netstat -a | grep -i listen # ps -ef If non-routing services, including Web servers, file servers, DNS servers, or applications servers, but excluding management services such as SSH and SNMP, are running on the system, this is a finding.

Fix: F-32418r1_fix

Ensure only authorized software is loaded on a designated router. Authorized software will be limited to the most current version of routing protocols and SSH for system administration purposes.

c

The system must not use UDP for NIS/NIS+.

AC-17 - High - CCI-001436 - V-4399 - SV-37739r1_rule

RMF Control

AC-17

Severity

H

CCI

Version

GEN006380

Vuln IDs

V-4399

Rule IDs

SV-37739r1_rule

Implementing Network Information Service (NIS) or NIS+ under UDP may make the system more susceptible to a Denial of Service attack and does not provide the same quality of service as TCP.System AdministratorECSC-1

Checks: C-36936r1_chk

If the system does not use NIS or NIS+, this is not applicable. Check if NIS or NIS+ is implemented using UDP. Procedure: # rpcinfo -p | grep yp | grep udp If NIS or NIS+ is implemented using UDP, this is a finding.

Fix: F-32201r1_fix

Configure the system to not use UDP for NIS and NIS+. Consult vendor documentation for the required procedure.

b

All .rhosts, .shosts, or host.equiv files must only contain trusted host-user pairs.

CM-6 - Medium - CCI-000366 - V-4427 - SV-37437r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN002020

Vuln IDs

V-4427

Rule IDs

SV-37437r1_rule

If these files are not properly configured, they could allow malicious access by unknown malicious users from untrusted hosts who could compromise the system.System AdministratorECCD-1, ECCD-2

Checks: C-36055r1_chk

Locate and examine all r-commands access control files. Procedure: # find / -name .rhosts # more /<directorylocation>/.rhosts # find / -name .shosts # more /<directorylocation>/.shosts # find / -name hosts.equiv # more /<directorylocation>/hosts.equiv # find / -name shosts.equiv # more /<directorylocation>/shosts.equiv If any .rhosts, .shosts, hosts.equiv, or shosts.equiv file contains other than host-user pairs, this is a finding.

Fix: F-31299r1_fix

If possible, remove the .rhosts, .shosts, hosts.equiv, and shosts.equiv files. If the files are required, remove any content from the files except for necessary host-user pairs.

b

All .rhosts, .shosts, .netrc, or hosts.equiv files must be accessible by only root or the owner.

AC-6 - Medium - CCI-000225 - V-4428 - SV-37385r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN002060

Vuln IDs

V-4428

Rule IDs

SV-37385r1_rule

If these files are accessible by users other than root or the owner, they could be used by a malicious user to set up a system compromise.System AdministratorECLP-1

Checks: C-36072r1_chk

Procedure: # ls -l /etc/hosts.equiv # ls -l /etc/ssh/shosts.equiv # find / -name .rhosts # ls -al <home directory>/.rhosts # find / -name .shosts # ls -al <home directory>/.shosts # find / -name .netrc # ls -al <home directory>/.netrc If the .rhosts, .shosts, hosts.equiv, or shosts.equiv files have permissions greater than 600, then this is a finding. If the /etc/hosts.equiv, or /etc/ssh/shosts.equiv files are not owned by root, this is a finding. Any .rhosts, .shosts and .netrc files outside of home directories have no meaning and are not subject to this rule If the ~/.rhosts or ~/.shosts are not owned by the owner of the home directory where they are immediately located or by root, this is a finding.

Fix: F-31316r1_fix

Ensure the permission for these files is set to 600 or more restrictive and their owner is root or the same as the owner of the home directory in which they reside. Procedure: # chmod 600 /etc/hosts.equiv # chmod 600 /etc/ssh/shosts.equiv # chown root /etc/hosts.equiv # chown root /etc/ssh/shosts.equiv # find / -name .rhosts # chmod 600 /<home directory>/.rhosts # chown <home directory owner> <home directory>/.rhosts # find / -name .shosts # chmod 600 <directory location>/.shosts # chown <home directory owner> <home directory>/.shosts # find / -name .netrc # chmod 600 <directory location>/.netrc # chown <home directory owner> <home directory>/.netrc

b

The cron.deny file must be owned by root, bin, or sys.

AC-6 - Medium - CCI-000225 - V-4430 - SV-27374r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003260

Vuln IDs

V-4430

Rule IDs

SV-27374r1_rule

Cron daemon control files restrict the scheduling of automated tasks and must be protected. System AdministratorECLP-1

Checks: C-28527r1_chk

# ls -lL /etc/cron.deny If the cron.deny file is not owned by root, sys, or bin, this is a finding.

Fix: F-24620r1_fix

# chown root /etc/cron.deny

c

The rsh daemon must not be running.

AC-17 - High - CCI-000068 - V-4687 - SV-37441r1_rule

RMF Control

AC-17

Severity

H

CCI

Version

GEN003820

Vuln IDs

V-4687

Rule IDs

SV-37441r1_rule

The rshd process provides a typically unencrypted, host-authenticated remote access service. SSH should be used in place of this service.Information Assurance OfficerSystem AdministratorEBRU-1

Checks: C-36113r1_chk

Check to see if rshd is configured to run on startup. Procedure: # grep disable /etc/xinetd.d/rsh If /etc/xinetd.d/rsh exists and rsh is found to be enabled, this is a finding.

Fix: F-31359r1_fix

Edit /etc/xinetd.d/rsh and set "disable=yes".

c

The rexec daemon must not be running.

AC-17 - High - CCI-001435 - V-4688 - SV-37443r1_rule

RMF Control

AC-17

Severity

H

CCI

CCI-001435

Version

GEN003840

Vuln IDs

V-4688

Rule IDs

SV-37443r1_rule

The rexecd process provides a typically unencrypted, host-authenticated remote access service. SSH should be used in place of this service.trueSystem AdministratorInformation Assurance OfficerECSC-1

Checks: C-36115r1_chk

# grep disable /etc/xinetd.d/rexec If the service file exists and is not disabled, this is a finding.

Fix: F-31361r1_fix

Edit /etc/xinetd.d/rexec and set "disable=yes"

c

The SMTP service must be an up-to-date version.

SI-2 - High - CCI-001230 - V-4689 - SV-37507r2_rule

RMF Control

SI-2

Severity

H

CCI

CCI-001230

Version

GEN004600

Vuln IDs

V-4689

Rule IDs

SV-37507r2_rule

The SMTP service version on the system must be current to avoid exposing vulnerabilities present in unpatched versions.System Administrator

Checks: C-36166r2_chk

Determine the version of the SMTP service software. Procedure: #rpm -q sendmail RedHat sendmail 8.13.8-8 is the latest required version. If the RedHat sendmail is installed and the version is not at least 8.13.8-8, this is a finding. #rpm -q postfix RedHat postfix-2.3.3-6-el5 is the latest required version. If the postfix is installed and the version is not at least postfix-2.3.3-6-el5, this is a finding.

Fix: F-31417r1_fix

Obtain and install a newer version of the SMTP service software (sendmail or Postfix) from RedHat.

c

The sendmail server must have the debug feature disabled.

CM-6 - High - CCI-000366 - V-4690 - SV-37508r1_rule

RMF Control

CM-6

Severity

H

CCI

Version

GEN004620

Vuln IDs

V-4690

Rule IDs

SV-37508r1_rule

Debug mode is a feature present in older versions of sendmail which, if not disabled, may allow an attacker to gain access to a system through the sendmail service.System AdministratorECSC-1

Checks: C-36167r2_chk

Check for an enabled "debug" command provided by the SMTP service. Procedure: # telnet localhost 25 debug If the command does not return a 500 error code of "command unrecognized" or a 550 error code of "access denied", this is a finding. The RHEL distribution ships with sendmail Version 8.13.8 which is not vulnerable. This should never be a finding.

Fix: F-31418r1_fix

Obtain and install a newer version of the SMTP service software (sendmail or Postfix) from RedHat.

c

The SMTP service must not have a uudecode alias active.

SI-2 - High - CCI-001230 - V-4691 - SV-37509r1_rule

RMF Control

SI-2

Severity

H

CCI

CCI-001230

Version

GEN004640

Vuln IDs

V-4691

Rule IDs

SV-37509r1_rule

A common configuration for older Mail Transfer Agents (MTAs) is to include an alias for the decode user. All mail sent to this user is sent to the uudecode program, which automatically converts and stores files. By sending mail to the decode or the uudecode aliases present on some systems, a remote attacker may be able to create or overwrite files on the remote host. This could possibly be used to gain remote access.System AdministratorECSC-1

Checks: C-36169r1_chk

Check the SMTP service for an active "decode" command. Procedure: # telnet localhost 25 decode If the command does not return a 500 error code of "command unrecognized", this is a finding.

Fix: F-31420r1_fix

Disable mail aliases for decode and uudecode. If the /etc/aliases or /usr/lib/aliases (mail alias) file contains entries for these programs, remove them or disable them by placing "#" at the beginning of the line, and then executing the new aliases command. For more information on mail aliases, refer to the man page for aliases. Disabled aliases would be similar to these examples: # decode: |/usr/bin/uudecode # uudecode: |/usr/bin/uuencode -d

a

The SMTP service must not have the EXPN feature active.

CM-6 - Low - CCI-000366 - V-4692 - SV-37510r1_rule

RMF Control

CM-6

Severity

L

CCI

Version

GEN004660

Vuln IDs

V-4692

Rule IDs

SV-37510r1_rule

The SMTP EXPN function allows an attacker to determine if an account exists on a system, providing significant assistance to a brute force attack on user accounts. EXPN may also provide additional information concerning users on the system, such as the full names of account owners.False positives may occur with the SMTP EXPN check. According to RFC821, it is acceptable for a server to respond with a 250 (success) or 550 (failure) when the server supports the EXPN command. For example, some servers return "550 EXPN command not available," meaning the command is not supported and the machine is not vulnerable. However, a result of "550 that is a mailing list, not a user" would be a failure code, but not an indication of an error, and the machine would be vulnerable. If a false positive is suspected, check the log file for the response from the server.System AdministratorECSC-1

Checks: C-36170r1_chk

This vulnerability is applicable only to sendmail. If Postfix is the SMTP service for the system this will never be a finding. Procedure: Determine if EXPN is disabled. # grep -v "^#" /etc/mail/sendmail.cf |grep -i PrivacyOptions If nothing is returned or the returned line does not contain "noexpn", this is a finding.

Fix: F-31421r1_fix

Rebuild /etc/mail/sendmail.cf with the "noexpn" Privacy Flag set. Procedure: Edit /etc/mail/sendmail.mc resetting the Privacy Flags to the default: define('confPRIVACYFLAGS', 'authwarnings,novrfy,noexpn,restrictqrun')dnl Rebuild the sendmail.cf file with: # make -C /etc/mail Restart the sendmail service. # service sendmail restart

a

The SMTP service must not have the Verify (VRFY) feature active.

CM-6 - Low - CCI-000366 - V-4693 - SV-37511r1_rule

RMF Control

CM-6

Severity

L

CCI

Version

GEN004680

Vuln IDs

V-4693

Rule IDs

SV-37511r1_rule

The VRFY command allows an attacker to determine if an account exists on a system, providing significant assistance to a brute force attack on user accounts. VRFY may provide additional information about users on the system, such as the full names of account owners.System AdministratorECSC-1

Checks: C-36171r1_chk

Determine if VRFY is disabled. Procedure: # telnet localhost 25 vrfy root If the command does not return a 500 error code of "command unrecognized", this is a finding. or: # grep -v "^#" /etc/mail/sendmail.cf |grep -i vrfy Verify the VRFY command is disabled with an entry in the sendmail.cf file. The entry could be any one of "Opnovrfy", "novrfy", or "goaway", which could also have other options included, such as "noexpn". The "goaway" argument encompasses many things, such as "novrfy" and "noexpn". If no setting to disable VRFY is found, this is a finding.

Fix: F-31422r1_fix

Add the "novrfy" flag to your sendmail in /etc/mail/sendmail.cf. Procedure: Edit the definition of "confPRIVACY_FLAGS" in /etc/mail/sendmail.mc to include "novrfy". Rebuild the sendmail.cf file with: # make -C /etc/mail Restart the sendmail service. # service sendmail restart

a

The sendmail service must not have the wizard backdoor active.

CM-6 - Low - CCI-000366 - V-4694 - SV-37513r1_rule

RMF Control

CM-6

Severity

L

CCI

Version

GEN004700

Vuln IDs

V-4694

Rule IDs

SV-37513r1_rule

Very old installations of the Sendmail mailing system contained a feature whereby a remote user connecting to the SMTP port can enter the WIZ command and be given an interactive shell with root privileges.System AdministratorECSC-1

Checks: C-36172r3_chk

Log into the sendmail server with telnet and test the "wiz" command. Procedure: # telnet localhost 25 Trying 127.0.0.1... Connected to locahost.localdomain (127.0.0.1). Escape character ... Once the telnet greeting is complete type: wiz If you do not get a "Command unrecognized: " message, this is a finding.

Fix: F-31423r2_fix

If the WIZ command exists on sendmail then the version of sendmail is archaic and should be replaced with the latest version from RedHat. WIZ is not available on any sendmail distribution of RHEL. However, if the WIZ command is enabled on sendmail, it should be disabled by adding this line to the sendmail.cf configuration file (note that it must be typed in uppercase): OW* For the change to take effect, kill the sendmail process, refreeze the sendmail.cf file, and restart the sendmail process.

c

Any active TFTP daemon must be authorized and approved in the system accreditation package.

AC-6 - High - CCI-000225 - V-4695 - SV-37676r1_rule

RMF Control

AC-6

Severity

H

CCI

Version

GEN005140

Vuln IDs

V-4695

Rule IDs

SV-37676r1_rule

TFTP is a file transfer protocol often used by embedded systems to obtain configuration data or software. The service is unencrypted and does not require authentication of requests. Data available using this service may be subject to unauthorized access or interception.Information Assurance OfficerSystem AdministratorDCSW-1

Checks: C-36864r2_chk

Determine if the TFTP daemon is active. # chkconfig --list | grep tftp If TFTP is found enabled ("on") and not documented using site-defined procedures, it is a finding.

Fix: F-31806r1_fix

Document or Disable the TFTP daemon. If the TFTP daemon is necessary on the system, document and justify its usage for approval from the IAO. If the TFTP daemon is not necessary on the system, turn it off. # chkconfig tftp off # service xinetd restart

b

The system must not have the UUCP service active.

AC-17 - Medium - CCI-001436 - V-4696 - SV-37688r1_rule

RMF Control

AC-17

Severity

M

CCI

Version

GEN005280

Vuln IDs

V-4696

Rule IDs

SV-37688r1_rule

The UUCP utility is designed to assist in transferring files, executing remote commands, and sending e-mail between UNIX systems over phone lines and direct connections between systems. The UUCP utility is a primitive and arcane system with many security issues. There are alternate data transfer utilities/products that can be configured to more securely transfer data by providing for authentication as well as encryption.System AdministratorECSC-1

Checks: C-36881r1_chk

# service uucp status if UUCP is "running", this is a finding.

Fix: F-31895r1_fix

# chkconfig uucp off # service uucp stop # service xinetd restart

c

X displays must not be exported to the world.

AC-6 - High - CCI-000225 - V-4697 - SV-37683r1_rule

RMF Control

AC-6

Severity

H

CCI

Version

GEN005200

Vuln IDs

V-4697

Rule IDs

SV-37683r1_rule

Open X displays allow an attacker to capture keystrokes and to execute commands remotely. Many users have their X Server set to “xhost +”, permitting access to the X Server by anyone, from anywhere.System AdministratorECSC-1

Checks: C-36872r2_chk

If Xwindows is not used on the system, this is not applicable. Check the output of the "xhost" command from an X terminal. Procedure: # xhost If the output reports access control is enabled (and possibly lists the hosts able to receive X window logins), this is not a finding. If the xhost command returns a line indicating access control is disabled, this is a finding. Note: It may be necessary to define the display if the command reports it cannot open the display. Procedure: $ DISPLAY=MachineName:0.0; export DISPLAY MachineName may be replaced with an Internet Protocol Address. Repeat the check procedure after setting the display.

Fix: F-31847r1_fix

If using an xhost-type authentication the "xhost -" command can be used to remove current trusted hosts and then selectively allow only trusted hosts to connect with "xhost +" commands. A cryptographically secure authentication, such as provided by the xauth program, is always preferred. Refer to your X11 server's documentation for further security information.

a

The system must not have the finger service active.

AC-4 - Low - CCI-001551 - V-4701 - SV-37445r1_rule

RMF Control

AC-4

Severity

L

CCI

Version

GEN003860

Vuln IDs

V-4701

Rule IDs

SV-37445r1_rule

The finger service provides information about the system's users to network clients. This information could expose more information for potential used in subsequent attacks.System AdministratorDCPP-1

Checks: C-36117r1_chk

# grep disable /etc/xinetd.d/finger If the finger service is not disabled, this is a finding.

Fix: F-31363r1_fix

Edit /etc/xinetd.d/finger and set "disable=yes"

b

If the system is an anonymous FTP server, it must be isolated to the DMZ network.

IA-4 - Medium - CCI-000787 - V-4702 - SV-37528r1_rule

RMF Control

IA-4

Severity

M

CCI

CCI-000787

Version

GEN004840

Vuln IDs

V-4702

Rule IDs

SV-37528r1_rule

Anonymous FTP is a public data service which is only permitted in a server capacity when located on the DMZ network.Information Assurance OfficerSystem AdministratorECSC-1

Checks: C-36187r1_chk

Use the command "ftp" to connect the system's FTP service. Attempt to log into this host with a user name of anonymous and a password of guest (also try the password of guest@mail.com). If the logon is not successful, this check is Not Applicable. Ask the SA if the system is located on a DMZ network. If the system is not located on a DMZ network, this is a finding.

Fix: F-31442r1_fix

Remove anonymous ftp capability or move the system to a DMZ network.

c

The operating system must be a supported release.

SI-2 - High - CCI-001230 - V-11940 - SV-27049r2_rule

RMF Control

SI-2

Severity

H

CCI

CCI-001230

Version

GEN000100

Vuln IDs

V-11940

Rule IDs

SV-27049r2_rule

An operating system release is considered "supported" if the vendor continues to provide security patches for the product. With an unsupported release, it will not be possible to resolve security issues discovered in the system software.If an extended support agreement provides security patches for the unsupported product is procured from the vendor, this finding may be downgraded to a CAT III.System Administrator

Checks: C-27963r2_chk

Check the version of the operating system. Example: # cat /etc/redhat-release Vendor End-of-Support Information: Red Hat Enterprise 5: 31 Mar 2017 Check with the vendor for additional information. If the version installed is not supported, this is a finding.

Fix: F-11211r2_fix

Upgrade to a supported version of the operating system.

b

A file integrity tool must be used at least weekly to check for unauthorized file changes, particularly the addition of unauthorized system libraries or binaries, or for unauthorized modification to authorized system libraries or binaries.

RA-5 - Medium - CCI-001069 - V-11945 - SV-38178r3_rule

RMF Control

RA-5

Severity

M

CCI

CCI-001069

Version

GEN000220

Vuln IDs

V-11945

Rule IDs

SV-38178r3_rule

Changes in system libraries, binaries and other critical system files can indicate compromise or significant system events such as patching needing to be checked by automated processes and the results reviewed by the SA. NOTE: The frequency may be increased to daily, if necessary, in accordance with the contingency plan.System Administrator

Checks: C-37562r4_chk

Check for the presence of an aide on the system: # rpm –qa | grep aide If aide is not installed, ask the SA what file integrity tool is being used to check the system. Check the global crontabs for the presence of an "aide" job to run at least weekly, if aide is installed. Otherwise, check for the presence of a cron job to run the alternate file integrity checking application. # grep aide /etc/cron*/* If a tool is being run then the configuration file for the appropriate tool needs to be checked for selection lines /bin, /sbin, /lib, and /usr. Procedure: Check the root crontab (crontab -l) and the global crontabs in /etc/crontab, /etc/cron.d/* for the presence of an "aide" job to run at least weekly, which should have asterisks (*) in columns 3, 4, and 5. Check the weekly cron directory (/etc/cron.weekly) for any script running "aide --check" or "aide -C" or simply "aide". If there is not, this is a finding. NOTE: The frequency may be increased to daily, if necessary, in accordance with the contingency plan.

Fix: F-32806r3_fix

Establish an automated job, scheduled to run weekly or more frequently, to run "aide --check" which is the file integrity tool to check for unauthorized system libraries or binaries. NOTE: The frequency may be increased to daily, if necessary, in accordance with the contingency plan.

b

UIDs reserved for system accounts must not be assigned to non-system accounts.

CM-6 - Medium - CCI-000366 - V-11946 - SV-37155r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN000340

Vuln IDs

V-11946

Rule IDs

SV-37155r1_rule

Reserved UIDs are typically used by system software packages. If non-system accounts have UIDs in this range, they may conflict with system software, possibly leading to the user having permissions to modify system files.System AdministratorECSC-1

Checks: C-35863r2_chk

Check the UID assignments for all accounts. # cut -d: -f 1,3 /etc/passwd | egrep ":[1-4][0-9]{2}$|:[0-9]{1,2}$" Confirm all accounts with a UID of 499 and below are used by a system account. If a UID reserved for system accounts (0 - 499) is used by a non-system account, then this is a finding.

Fix: F-31119r1_fix

Change the UID numbers for non-system accounts with reserved UIDs (those less or equal to 499).

b

The system must require passwords contain a minimum of 15 characters.

IA-5 - Medium - CCI-000205 - V-11947 - SV-37260r2_rule

RMF Control

IA-5

Severity

M

CCI

CCI-000205

Version

GEN000580

Vuln IDs

V-11947

Rule IDs

SV-37260r2_rule

The use of longer passwords reduces the ability of attackers to successfully obtain valid passwords using guessing or exhaustive search techniques by increasing the password search space.System Administrator

Checks: C-35950r3_chk

Check the system password length setting. Procedure: Check the password minlen option # grep pam_cracklib.so /etc/pam.d/system-auth Confirm the minlen option is set to at least 15 as in the example below: password required pam_cracklib.so minlen=15 There may be other options on the line. If no such line is found, or the minlen is less than 15 this is a finding.

Fix: F-31206r2_fix

Edit "/etc/pam.d/system-auth" to include the line: password required pam_cracklib.so minlen=15 prior to the "password include system-auth-ac" line.

b

The system must require passwords contain at least one uppercase alphabetic character.

IA-5 - Medium - CCI-000192 - V-11948 - SV-41826r1_rule

RMF Control

IA-5

Severity

M

CCI

CCI-000192

Version

GEN000600

Vuln IDs

V-11948

Rule IDs

SV-41826r1_rule

To enforce the use of complex passwords, minimum numbers of characters of different classes are mandated. The use of complex passwords reduces the ability of attackers to successfully obtain valid passwords using guessing or exhaustive search techniques. Complexity requirements increase the password search space by requiring users to construct passwords from a larger character set than they may otherwise use.System AdministratorIAIA-1, IAIA-2

Checks: C-40120r1_chk

Check the ucredit setting. # grep ucredit /etc/pam.d/system-auth If ucredit is not set to -1, this is a finding.

Fix: F-35446r1_fix

Edit "/etc/pam.d/system-auth" to include the line: password required pam_cracklib.so ucredit=-1 prior to the "password include system-auth-ac" line.

b

The system must require passwords contain at least one numeric character.

IA-5 - Medium - CCI-000194 - V-11972 - SV-37281r1_rule

RMF Control

IA-5

Severity

M

CCI

CCI-000194

Version

GEN000620

Vuln IDs

V-11972

Rule IDs

SV-37281r1_rule

To enforce the use of complex passwords, minimum numbers of characters of different classes are mandated. The use of complex passwords reduces the ability of attackers to successfully obtain valid passwords using guessing or exhaustive search techniques. Complexity requirements increase the password search space by requiring users to construct passwords from a larger character set than they may otherwise use.System AdministratorIAIA-1, IAIA-2

Checks: C-35972r1_chk

Check the dcredit setting. Procedure: Check the password dcredit option # grep pam_cracklib.so /etc/pam.d/system-auth Confirm the dcredit option is set to -1 as in the example: password required pam_cracklib.so dcredit=-1 There may be other options on the line. If no such line is found, or the dcredit option is not -1 this is a finding.

Fix: F-31227r1_fix

Edit "/etc/pam.d/system-auth" to include the line: password required pam_cracklib.so dcredit=-1 prior to the "password include system-auth-ac" line.

b

The system must require passwords contain at least one special character.

IA-5 - Medium - CCI-001619 - V-11973 - SV-37287r1_rule

RMF Control

IA-5

Severity

M

CCI

CCI-001619

Version

GEN000640

Vuln IDs

V-11973

Rule IDs

SV-37287r1_rule

To enforce the use of complex passwords, minimum numbers of characters of different classes are mandated. The use of complex passwords reduces the ability of attackers to successfully obtain valid passwords using guessing or exhaustive search techniques. Complexity requirements increase the password search space by requiring users to construct passwords from a larger character set than they may otherwise use.System AdministratorIAIA-1, IAIA-2

Checks: C-35981r1_chk

Check the ocredit setting. Procedure: Check the password ocredit option # grep pam_cracklib.so /etc/pam.d/system-auth Confirm the ocredit option is set to -1 as in the example: password required pam_cracklib.so ocredit=-1 There may be other options on the line. If no such line is found, or the ocredit is not -1 this is a finding.

Fix: F-31235r1_fix

Edit "/etc/pam.d/system-auth" to include the line: password required pam_cracklib.so ocredit=-1 prior to the "password include system-auth-ac" line.

b

The system must require passwords contain no more than three consecutive repeating characters.

CM-6 - Medium - CCI-000366 - V-11975 - SV-37294r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN000680

Vuln IDs

V-11975

Rule IDs

SV-37294r1_rule

To enforce the use of complex passwords, the number of consecutive repeating characters is limited. Passwords with excessive repeated characters may be more vulnerable to password-guessing attacks.System AdministratorIAIA-1, IAIA-2

Checks: C-35986r1_chk

Check the maxrepeat setting. Procedure: Check the password maxrepeat configuration # grep pam_cracklib.so /etc/pam.d/system-auth If the maxrepeat option is missing, this is a finding. If the maxrepeat option is set to more than 3, this is a finding.

Fix: F-31243r1_fix

Edit "/etc/pam.d/system-auth" to include the line: password required pam_cracklib.so maxrepeat=3 prior to the "password include system-auth-ac" line.

b

User passwords must be changed at least every 60 days.

IA-5 - Medium - CCI-000180 - V-11976 - SV-37298r1_rule

RMF Control

IA-5

Severity

M

CCI

CCI-000180

Version

GEN000700

Vuln IDs

V-11976

Rule IDs

SV-37298r1_rule

Limiting the lifespan of authenticators limits the period of time an unauthorized user has access to the system while using compromised credentials and reduces the period of time available for password-guessing attacks to run against a single password.System Administrator

Checks: C-35993r1_chk

Check the max days field (the 5th field) of /etc/shadow. # more /etc/shadow If the max days field is equal to 0 or greater than 60 for any user, this is a finding.

Fix: F-31246r1_fix

Set the max days field to 60 for all user accounts. # passwd -x 60 <user>

b

All non-interactive/automated processing account passwords must be changed at least once per year or be locked.

IA-5 - Medium - CCI-000199 - V-11977 - SV-37302r1_rule

RMF Control

IA-5

Severity

M

CCI

CCI-000199

Version

GEN000740

Vuln IDs

V-11977

Rule IDs

SV-37302r1_rule

Limiting the lifespan of authenticators limits the period of time an unauthorized user has access to the system while using compromised credentials and reduces the period of time available for password-guessing attacks to run against a single password. Locking the password for non-interactive and automated processing accounts is preferred as it removes the possibility of accessing the account by a password. On some systems, locking the passwords of these accounts may prevent the account from functioning properly. Passwords for non-interactive/automated processing accounts must not be used for direct logon to the system.System AdministratorIAIA-1, IAIA-2

Checks: C-35997r2_chk

Ask the SA if there are any automated processing accounts on the system. If there are automated processing accounts on the system, ask the SA if the passwords for those automated accounts are changed at least once a year or are locked. If SA indicates passwords for automated processing accounts are not changed once per year or are not locked, this is a finding.

Fix: F-31249r2_fix

Implement or establish procedures to change the passwords of automated processing accounts at least once per year or lock them.

b

The root account must not be used for direct log in.

IA-2 - Medium - CCI-000770 - V-11979 - SV-37377r2_rule

RMF Control

IA-2

Severity

M

CCI

Version

GEN001020

Vuln IDs

V-11979

Rule IDs

SV-37377r2_rule

Direct login with the root account prevents individual user accountability. Acceptable non-routine uses of the root account for direct login are limited to emergency maintenance, the use of single-user mode for maintenance, and situations where individual administrator accounts are not available.System Administrator

Checks: C-36064r5_chk

Check if root is used for direct logins. Procedure: # last root | grep -v reboot Direct logins are indicated by the presence of a terminal or pseudo-terminal ID and/or X display name in the output of the last command. If any direct login records for root are listed, this is a finding.

Fix: F-31308r1_fix

Enforce policy requiring all root account access is attained by first logging into a user account and then becoming root preferably through the use of "sudo" which provides traceability to the command level. If that is not workable then using "su" to access the root account will provide traceability to the login user.

b

The system must log successful and unsuccessful access to the root account.

AU-2 - Medium - CCI-000126 - V-11980 - SV-37378r3_rule

RMF Control

AU-2

Severity

M

CCI

Version

GEN001060

Vuln IDs

V-11980

Rule IDs

SV-37378r3_rule

If successful and unsuccessful logins and logouts are not monitored or recorded, access attempts cannot be tracked. Without this logging, it may be impossible to track unauthorized access to the system.System Administrator

Checks: C-36065r6_chk

Check the log files to determine if access to the root account is being logged. Procedure: Depending on what system is used for log processing either /etc/syslog.conf or /etc/rsyslog.conf will be the logging configuration file. Examine /etc/syslog.conf or /etc/rsyslog.conf to confirm the location to which "authpriv" messages will be directed. The default syslog.conf or rsyslog.conf uses /var/log/messages and /var/log/secure but this needs to be confirmed. # grep @ /etc/syslog.conf Or: # grep @ /etc/rsyslog.conf If a line starting with "*.*" is returned then all syslog messages will be sent to system whose address appears after the "@". In this case syslog may or may not be configured to also log "authpriv" messages locally. # grep authpriv /etc/syslog.conf Or: # grep authpriv /etc/rsyslog.conf If any lines are returned which do not start with "#" the "authpriv" messages will be sent to the indicated files or remote systems. Try to "su -" and enter an incorrect password. If there are no records indicating the authentication failure, this is a finding.

Fix: F-31309r5_fix

Troubleshoot the system logging configuration to provide for logging of root account login attempts. Procedure: Edit /etc/syslog.conf or /etc/rsyslog.conf to make sure "authpriv.*" messages are directed to a file or remote system. Examine /etc/audit/audit.rules to ensure user authentication messages have not been specifically excluded. Remove any entries that correspond to: -a exclude,never -Fmsgtype=USER_START -a exclude,never -Fmsgtype=USER_LOGIN -a exclude,never -Fmsgtype=USER_AUTH -a exclude,never -Fmsgtype=USER_END -a exclude,never -Fmsgtype=USER_ACCT

b

All global initialization files must have mode 0644 or less permissive.

AC-6 - Medium - CCI-000225 - V-11981 - SV-37275r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001720

Vuln IDs

V-11981

Rule IDs

SV-37275r1_rule

Global initialization files are used to configure the user's shell environment upon login. Malicious modification of these files could compromise accounts upon logon.System AdministratorECLP-1

Checks: C-35967r1_chk

Check global initialization files permissions: # ls -l /etc/bashrc # ls -l /etc/csh.cshrc # ls -l /etc/csh.login # ls -l /etc/csh.logout # ls -l /etc/environment # ls -l /etc/ksh.kshrc # ls -l /etc/profile # ls -l /etc/suid_profile # ls -l /etc/profile.d/* If global initialization files are more permissive than 0644, this is a finding.

Fix: F-31223r1_fix

Change the mode of the global initialization file(s) to 0644. # chmod 0644 <global initialization file>

b

All global initialization files must be owned by root.

AC-6 - Medium - CCI-000225 - V-11982 - SV-37283r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001740

Vuln IDs

V-11982

Rule IDs

SV-37283r1_rule

Global initialization files are used to configure the user's shell environment upon login. Malicious modification of these files could compromise accounts upon logon. Failure to give ownership of sensitive files or utilities to root or bin provides the designated owner and unauthorized users with the potential to access sensitive information or change the system configuration which could weaken the system's security posture.ECLP-1

Checks: C-35974r1_chk

Check the ownership of global initialization files. Procedure: # ls -lL etc/bashrc /etc/csh.cshrc /etc/csh.login /etc/csh.logout /etc/environment /etc/ksh.kshrc /etc/profile /etc/suid_profile /etc/profile.d/* This should show information for each file. Examine to ensure the owner is always root or: # ls etc/bashrc /etc/csh.cshrc /etc/csh.login /etc/csh.logout /etc/environment /etc/ksh.kshrc /etc/profile /etc/suid_profile /etc/profile.d/* 2>null|xargs stat -L -c %U:%n|egrep -v "^root" This will show you only the owner and filename of files not owned by root. If any global initialization file is not owned by root, this is a finding.

Fix: F-31229r1_fix

Change the ownership of global initialization files with incorrect ownership. Procedure: # chown root <global initialization files> or: # ls etc/bashrc /etc/csh.cshrc /etc/csh.login /etc/csh.logout /etc/environment /etc/ksh.kshrc /etc/profile /etc/suid_profile /etc/profile.d/* 2>null|xargs stat -L -c %U:%n|egrep -v "^root"|cut -d: -f2|xargs chown root will set the owner of all files not currently owned by root to root.

b

All global initialization files must be group-owned by root, sys, bin, other, system, or the system default.

AC-6 - Medium - CCI-000225 - V-11983 - SV-37285r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001760

Vuln IDs

V-11983

Rule IDs

SV-37285r1_rule

Global initialization files are used to configure the user's shell environment upon login. Malicious modification of these files could compromise accounts upon logon. Failure to give ownership of sensitive files or utilities to root or bin provides the designated owner and unauthorized users with the potential to access sensitive information or change the system configuration which could weaken the system's security posture.System AdministratorECLP-1

Checks: C-35979r1_chk

Check the group ownership of global initialization files. Procedure: # ls -lL etc/bashrc /etc/csh.cshrc /etc/csh.login /etc/csh.logout /etc/environment /etc/ksh.kshrc /etc/profile /etc/suid_profile /etc/profile.d/* This should show information for each file. Examine to ensure the group is always root or: # ls -lL etc/bashrc /etc/csh.cshrc /etc/csh.login /etc/csh.logout /etc/environment /etc/ksh.kshrc /etc/profile /etc/suid_profile /etc/profile.d/* 2>null|sed "s/^[^\/]*//"|xargs stat -L -c %G:%n|egrep -v "^(root|sys|bin|other):" will show you only the group and filename of files not owned by one of the approved groups. If any global initialization file is not group-owned by root, sys, bin, other, system, or the system default, this is a finding.

Fix: F-31232r1_fix

Change the group ownership of the global initialization file(s) with incorrect group ownership. Procedure: # chgrp root <global initialization file> or: # ls -lL /etc/bashrc /etc/csh.cshrc /etc/csh.login /etc/csh.logout /etc/environment /etc/ksh.kshrc /etc/profile /etc/suid_profile /etc/profile.d/* 2>null|sed "s/^[^\/]*//"|xargs stat -L -c %G:%n|egrep -v "^(root|sys|bin|other):"|cut -d: -f2|xargs chgrp root will set the group of all files not currently owned by an approved group to root.

b

All skeleton files and directories (typically in /etc/skel) must be owned by root or bin.

AC-6 - Medium - CCI-000225 - V-11984 - SV-37300r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001820

Vuln IDs

V-11984

Rule IDs

SV-37300r1_rule

If the skeleton files are not protected, unauthorized personnel could change user startup parameters and possibly jeopardize user files. Failure to give ownership of sensitive files or utilities to root or bin provides the designated owner and unauthorized users with the potential to access sensitive information or change the system configuration which could weaken the system's security posture.System AdministratorECLP-1

Checks: C-35995r1_chk

Check skeleton files ownership. # ls -alL /etc/skel If a skeleton file is not owned by root or bin, this is a finding.

Fix: F-31248r1_fix

b

All global initialization files' executable search paths must contain only absolute paths.

CM-6 - Medium - CCI-000366 - V-11985 - SV-37420r2_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN001840

Vuln IDs

V-11985

Rule IDs

SV-37420r2_rule

The executable search path (typically the PATH environment variable) contains a list of directories for the shell to search to find executables. If this path includes the current working directory or other relative paths, executables in these directories may be executed instead of system commands. This variable is formatted as a colon-separated list of directories. If there is an empty entry, such as a leading or trailing colon, or two consecutive colons, this is interpreted as the current working directory. Paths starting with a slash (/) are absolute paths.System Administrator

Checks: C-35932r2_chk

Check the global initialization files' executable search paths. Procedure: # grep PATH /etc/bashrc /etc/csh.cshrc /etc/csh.login /etc/csh.logout /etc/environment /etc/ksh.kshrc /etc/profile /etc/suid_profile /etc/profile.d/* This variable is formatted as a colon-separated list of directories. If there is an empty entry, such as a leading or trailing colon, or two consecutive colons, this is a finding. If an entry begins with a character other than a slash (/) or other than "$PATH", it is a relative path, and this is a finding.

Fix: F-31187r1_fix

Edit the global initialization file(s) with PATH variables containing relative paths. Edit the file and remove the relative path from the PATH variable.

b

All local initialization files' executable search paths must contain only absolute paths.

CM-6 - Medium - CCI-000366 - V-11986 - SV-37432r3_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN001900

Vuln IDs

V-11986

Rule IDs

SV-37432r3_rule

The executable search path (typically the PATH environment variable) contains a list of directories for the shell to search to find executables. If this path includes the current working directory or other relative paths, executables in these directories may be executed instead of system commands. This variable is formatted as a colon-separated list of directories. If there is an empty entry, such as a leading or trailing colon, or two consecutive colons, this is interpreted as the current working directory. Paths starting with a slash (/) are absolute paths.System Administrator

Checks: C-35985r4_chk

Verify local initialization files have executable search path containing only absolute paths or relative paths are necessary and documented. Procedure: NOTE: This must be done in the BASH shell. # cut -d: -f6 /etc/passwd |xargs -n1 -IDIR find DIR -name ".*" -type f -maxdepth 1 -exec grep -l PATH {} \; This variable is formatted as a colon-separated list of directories. If there is an empty entry, such as a leading or trailing colon, or two consecutive colons, this is a finding. If an entry begins with a character other than a slash (/) or other than "$PATH", it is a relative path. Ask the SA or IAO if the relative path is required for the operation of a specific application. If it is not, this is a finding.

Fix: F-31242r2_fix

Edit the local initialization file and remove the relative path entry from the executable search path variable. If this is not feasible, justify and document the necessity of having the relative path for a specific application.

b

The .rhosts, .shosts, hosts.equiv, shosts.equiv, /etc/passwd, /etc/shadow, and/or /etc/group files must not contain a plus (+) without defining entries for NIS+ netgroups.

CM-6 - Medium - CCI-000366 - V-11987 - SV-37435r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN001980

Vuln IDs

V-11987

Rule IDs

SV-37435r1_rule

A plus (+) in system accounts files causes the system to lookup the specified entry using NIS. If the system is not using NIS, no such entries should exist.System AdministratorECCD-1, ECCD-2

Checks: C-36048r1_chk

Check system configuration files for plus (+) entries. Procedure: # find / -name .rhosts # grep + /<directorylocation>/.rhosts # find / -name .shosts # grep + /<directorylocation>/.shosts # find / -name hosts.equiv # grep + /<directorylocation>/hosts.equiv # find / -name shosts.equiv # grep + /<directorylocation>/shosts.equiv # grep + /etc/passwd # grep + /etc/shadow # grep + /etc/group If the .rhosts, .shosts, hosts.equiv, shosts.equiv, /etc/passwd, /etc/shadow, and/or /etc/group files contain a plus (+) and do not define entries for NIS+ netgroups, this is a finding.

Fix: F-31292r1_fix

Edit the .rhosts, .shosts, hosts.equiv, shosts.equiv, /etc/passwd, /etc/shadow, and/or /etc/group files and remove entries containing a plus (+).

c

There must be no .rhosts, .shosts, hosts.equiv, or shosts.equiv files on the system.

CM-6 - High - CCI-000366 - V-11988 - SV-37370r1_rule

RMF Control

CM-6

Severity

H

CCI

Version

GEN002040

Vuln IDs

V-11988

Rule IDs

SV-37370r1_rule

The .rhosts, .shosts, hosts.equiv, and shosts.equiv files are used to configure host-based authentication for individual users or the system. Host-based authentication is not sufficient for preventing unauthorized access to the system.Information Assurance OfficerSystem AdministratorECCD-1, ECCD-2

Checks: C-36057r1_chk

Check for the existence of the files. # find / -name .rhosts # find / -name .shosts # find / -name hosts.equiv # find / -name shosts.equiv If .rhosts, .shosts, hosts.equiv, or shosts.equiv are found and their use has not been documented and approved by the IAO, this is a finding.

Fix: F-31301r1_fix

Remove all the r-commands access control files. Procedure: # find / -name .rhosts -exec rm {} \; # find / -name .shosts -exec rm {} \; # find / -name hosts.equiv -exec rm {} \; # find / -name shosts.equiv -exec rm {} \;

b

The .rhosts file must not be supported in PAM.

CM-6 - Medium - CCI-000366 - V-11989 - SV-37389r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN002100

Vuln IDs

V-11989

Rule IDs

SV-37389r1_rule

.rhosts files are used to specify a list of hosts permitted remote access to a particular account without authenticating. The use of such a mechanism defeats strong identification and authentication requirements.Information Assurance OfficerSystem AdministratorECCD-1, ECCD-2

Checks: C-36075r1_chk

Check the PAM configuration for rhosts_auth. Example: # grep rhosts_auth /etc/pam.d/* If a rhosts_auth entry is found, this is a finding.

Fix: F-31319r1_fix

Edit the file(s) in /etc/pam.d referencing the rhosts_auth module, and remove the references to the rhosts_auth module.

b

All public directories must be group-owned by root, sys, bin, or an application group.

AC-6 - Medium - CCI-000225 - V-11990 - SV-37893r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN002540

Vuln IDs

V-11990

Rule IDs

SV-37893r1_rule

If a public directory has the sticky bit set and is not group-owned by a privileged GID, unauthorized users may be able to modify files created by others. The only authorized public directories are those temporary directories supplied with the system or those designed to be temporary file repositories. The setting is normally reserved for directories used by the system and by users for temporary file storage, (e.g., /tmp), and for directories requiring global read/write access.System AdministratorECLP-1

Checks: C-37119r2_chk

Check the group-ownership of public directories. Procedure: # find / -type d -perm -1002 -exec ls -ld {} \; If any public directory is not group-owned by root, sys, bin, or an application group, this is a finding.

Fix: F-32387r1_fix

Change the group-ownership of the public directory. Procedure: # chgrp root /tmp (Replace root with a different system group and/or /tmp with a different public directory as necessary.)

b

Crontabs must be owned by root or the crontab creator.

AC-6 - Medium - CCI-000225 - V-11994 - SV-37392r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003040

Vuln IDs

V-11994

Rule IDs

SV-37392r1_rule

To protect the integrity of scheduled system jobs and prevent malicious modification to these jobs, crontab files must be secured.System AdministratorDCSL-1

Checks: C-36076r1_chk

List all crontabs on the system. # ls -lL /var/spool/cron # ls -lL /etc/cron.d /etc/crontab /etc/cron.daily /etc/cron.hourly /etc/cron.monthly /etc/cron.weekly or # ls -lL /etc/cron*|grep -v deny If any crontab is not owned by root or the creating user, this is a finding.

Fix: F-31322r1_fix

Change the crontab owner to root or the crontab creator. # chown root <crontab file> or # chown <user> <crontab file>

b

Default system accounts (with the exception of root) must not be listed in the cron.allow file or must be included in the cron.deny file, if cron.allow does not exist.

AC-6 - Medium - CCI-000225 - V-11995 - SV-27338r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003060

Vuln IDs

V-11995

Rule IDs

SV-27338r1_rule

To centralize the management of privileged account crontabs, of the default system accounts, only root may have a crontab.System AdministratorECPA-1

Checks: C-28474r1_chk

Check the cron.allow and cron.deny files for the system. # more /etc/cron.allow # more /etc/cron.deny If a default system account (such as bin, sys, adm, or others, traditionally UID less than 500) is listed in the cron.allow file, or not listed in the cron.deny file and if no cron.allow file exists, this is a finding.

Fix: F-31374r1_fix

Remove default system accounts (such as bin, sys, adm, or others, traditionally UID less than 500) from the cron.allow file if it exists, or add those accounts to the cron.deny file.

a

Process core dumps must be disabled unless needed.

CM-6 - Low - CCI-000366 - V-11996 - SV-37546r2_rule

RMF Control

CM-6

Severity

L

CCI

Version

GEN003500

Vuln IDs

V-11996

Rule IDs

SV-37546r2_rule

Process core dumps contain the memory in use by the process when it crashed. Process core dump files can be of significant size and their use can result in file systems filling to capacity, which may result in Denial of Service. Process core dumps can be useful for software debugging. System Administrator

Checks: C-36201r2_chk

# ulimit -Hc If the above command does not return 0 and the enabling of core dumps has not been documented and approved by the IAO, this a finding.

Fix: F-31460r3_fix

Edit /etc/security/limits.conf and set a hard limit for "core" to 0 for all users. A new login will be required for the changes to take effect.

a

The kernel core dump data directory must be owned by root.

AC-6 - Low - CCI-000225 - V-11997 - SV-37570r2_rule

RMF Control

AC-6

Severity

L

CCI

Version

GEN003520

Vuln IDs

V-11997

Rule IDs

SV-37570r2_rule

Kernel core dumps may contain the full contents of system memory at the time of the crash. As the system memory may contain sensitive information, it must be protected accordingly. If the kernel core dump data directory is not owned by root, the core dumps contained in the directory may be subject to unauthorized access.System Administrator

Checks: C-36351r2_chk

Verify the location of the kernel core dump data directory: # grep “path” /etc/kdump.conf Note: If this setting is not configured or commented out, the default kernel dump data directory is /var/crash. Check the ownership of the dump data directory: # ls –ld <path to kernel core dump data directory> If the kernel core dump data directory is not owned by root, this is a finding.

Fix: F-31608r3_fix

Change the owner of the kernel core dump data directory to root. # chown root <path to kernel core dump data directory>

b

The system must implement non-executable program stacks.

CM-6 - Medium - CCI-000366 - V-11999 - SV-27414r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN003540

Vuln IDs

V-11999

Rule IDs

SV-27414r1_rule

A common type of exploit is the stack buffer overflow. An application receives, from an attacker, more data than it is prepared for and stores this information on its stack, writing beyond the space reserved for it. This can be designed to cause execution of the data written on the stack. One mechanism to mitigate this vulnerability is for the system to not allow the execution of instructions in sections of memory identified as part of the stack.System AdministratorECSC-1

Checks: C-28600r1_chk

Verify "exec_shield" and "randomize_va_space" have not been changed from the default "1" settings. Procedure: #sysctl kernel.exec-shield If the return value is not: kernel.exec-shield = 1 this is a finding. #sysctl kernel.randomize_va_space If the return value is not: kernel.randomize_va_space = 1 this is a finding.

Fix: F-24686r1_fix

Examine /etc/sysctl.conf for "kernel.exec-shield" and "kernel.randomize_va_space" entries and if found remove them. The system default of "1" enables these modules.

b

The system must not forward IPv4 source-routed packets.

AC-4 - Medium - CCI-001551 - V-12002 - SV-29795r1_rule

RMF Control

AC-4

Severity

M

CCI

Version

GEN003600

Vuln IDs

V-12002

Rule IDs

SV-29795r1_rule

Source-routed packets allow the source of the packet to suggest routers forward the packet along a different path than configured on the router, which can be used to bypass network security measures. This requirement applies only to the forwarding of source-routed traffic, such as when IPv4 forwarding is enabled and the system is functioning as a router.System AdministratorECSC-1

Checks: C-36392r1_chk

Verify the system does not accept source-routed IPv4 packets. Procedure: # grep [01] /proc/sys/net/ipv4/conf/*/accept_source_route|egrep "default|all" If all of the returned lines do not end with 0, this is a finding. Note: The same setting is used by Linux for both the local acceptance and forwarding of source-routed IPv4 packets.

Fix: F-31612r1_fix

Configure the system to not accept source-routed IPv4 packets. Edit /etc/sysctl.conf and add a setting for "net.ipv4.conf.all.accept_source_route=0" and "net.ipv4.conf.default.accept_source_route=0". Reload the sysctls. Procedure: # sysctl -p

a

A separate file system must be used for user home directories (such as /home or an equivalent).

SC-32 - Low - CCI-001208 - V-12003 - SV-37640r1_rule

RMF Control

SC-32

Severity

L

CCI

Version

GEN003620

Vuln IDs

V-12003

Rule IDs

SV-37640r1_rule

The use of separate file systems for different paths can protect the system from failures resulting from a file system becoming full or failing.trueSystem AdministratorECSC-1

Checks: C-36838r1_chk

Determine if the /home path is a separate filesystem. # grep "/home " /etc/fstab If no result is returned, /home is not on a separate filesystem this is a finding.

Fix: F-31675r1_fix

Migrate the /home (or equivalent) path onto a separate file system.

b

The system must log informational authentication data.

AU-2 - Medium - CCI-000126 - V-12004 - SV-37404r2_rule

RMF Control

AU-2

Severity

M

CCI

Version

GEN003660

Vuln IDs

V-12004

Rule IDs

SV-37404r2_rule

Monitoring and recording successful and unsuccessful logins assists in tracking unauthorized access to the system.System Administrator

Checks: C-36086r3_chk

Depending on what system is used for log processing either /etc/syslog.conf or /etc/rsyslog.conf will be the logging configuration file. Check /etc/syslog.conf or /etc/rsyslog.conf and verify the authpriv facility is logging both the "notice" and "info" priority messages. Procedure: For a given action all messages of a higher severity or "priority" are logged. The three lowest priorities in ascending order are "debug", "info" and "notice". A priority of "info" will include "notice". A priority of "debug" includes both "info" and "notice". Enter/Input for syslog: # grep "authpriv.debug" /etc/syslog.conf # grep "authpriv.info" /etc/syslog.conf # grep "authpriv\.\*" /etc/syslog.conf Enter/Input for rsyslog: # grep "authpriv.debug" /etc/rsyslog.conf # grep "authpriv.info" /etc/rsyslog.conf # grep "authpriv\.\*" /etc/rsyslog.conf If an "authpriv.*", "authpriv.debug", or "authpriv.info" entry is not found, this is a finding.

Fix: F-31333r2_fix

Edit /etc/syslog.conf or /etc/rsyslog.conf and add local log destinations for "authpriv.*", "authpriv.debug" or "authpriv.info".

b

Inetd and xinetd must be disabled or removed if no network services utilizing them are enabled.

CM-2 - Medium - CCI-000305 - V-12005 - SV-27424r1_rule

RMF Control

CM-2

Severity

M

CCI

Version

GEN003700

Vuln IDs

V-12005

Rule IDs

SV-27424r1_rule

Unnecessary services should be disabled to decrease the attack surface of the system.System AdministratorECSC-1

Checks: C-28610r1_chk

# ps -ef |grep xinetd If xinetd is not running, this check is not a finding. # grep -v "^#" /etc/xinetd.conf # grep disable /etc/xinetd.d/* |grep no If no active services are found, and the inetd daemon is running, this is a finding.

Fix: F-24696r1_fix

# service xinetd stop ; chkconfig xinetd off

b

The SMTP service HELP command must not be enabled.

CM-6 - Medium - CCI-000366 - V-12006 - SV-37504r4_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN004540

Vuln IDs

V-12006

Rule IDs

SV-37504r4_rule

The HELP command should be disabled to mask version information. The version of the SMTP service software could be used by attackers to target vulnerabilities present in specific software versions.System Administrator

Checks: C-36162r2_chk

Check if Help is disabled. This rule is for "sendmail" only and not applicable to "Postfix". Procedure: # telnet localhost 25 > help If the help command returns any sendmail version information, this is a finding. If sendmail is not installed this check is not applicable.

Fix: F-31413r3_fix

To disable the SMTP HELP command, clear the Sendmail help file. # echo -n > /etc/mail/helpfile

b

Unencrypted FTP must not be used on the system.

CM-6 - Medium - CCI-000366 - V-12010 - SV-37515r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN004800

Vuln IDs

V-12010

Rule IDs

SV-37515r1_rule

: FTP is typically unencrypted and presents confidentiality and integrity risks. FTP may be protected by encryption in certain cases, such as when used in a Kerberos environment. SFTP and FTPS are encrypted alternatives to FTP.trueSystem AdministratorECSC-1

Checks: C-36174r3_chk

Perform the following to determine if unencrypted FTP is enabled: # chkconfig --list gssftp # chkconfig --list vsftpd If any of these services are found, ask the SA if these services are encrypted. If they are not, this is a finding.

Fix: F-31425r2_fix

Disable the FTP daemons. Procedure: # chkconfig gssftp off # chkconfig vsftpd off

b

All FTP users must have a default umask of 077.

AC-6 - Medium - CCI-000225 - V-12011 - SV-37555r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN005040

Vuln IDs

V-12011

Rule IDs

SV-37555r1_rule

The umask controls the default access mode assigned to newly created files. An umask of 077 limits new files to mode 700 or less permissive. Although umask is stored as a 4-digit number, the first digit representing special access modes is typically ignored or required to be zero (0).System AdministratorECCD-1, ECCD-2

Checks: C-36207r1_chk

Check the umask setting for FTP users. Procedure: For gssftp: Assuming an anonymous ftp user has been defined with no user initialization script invoked to change the umask # ftp localhost Name: (localhost:root): anonymous Password: anything ftp>umask If the umask value returned is not 077, this is a finding. or: # grep "server_args" /etc/xinetd.d/gssftp The default umask for FTP is "023" if the server _args entry does not contain "-u 077" this is a finding. For vsftp: # grep "_mask" /etc/vsftpd/vsftpd.conf The default "local_umask" setting is 077. If this has been changed, or the "anon_umask" setting is not 077, this is a finding.

Fix: F-31466r1_fix

Edit the initialization files for the ftp user and set the umask to 077. Procedure: For gssftp: Modify the /etc/xinetd.d/gssftp file adding "-u 077" to the server_args entry. For vsftp: Modify the "/etc/vsftpd/vsftpd.conf" setting "local_umask" and "anon_umask" to 077.

b

All .Xauthority files must have mode 0600 or less permissive.

AC-6 - Medium - CCI-000225 - V-12014 - SV-37679r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN005180

Vuln IDs

V-12014

Rule IDs

SV-37679r1_rule

.Xauthority files ensure the user is authorized to access specific X Windows host. Excessive permissions may permit unauthorized modification of these files, which could lead to Denial of Service to authorized access or allow unauthorized access to be obtained.System AdministratorECLP-1

Checks: C-36866r1_chk

Check the file permissions for the .Xauthority files. Procedure: # ls -la |egrep "(\.Xauthority|\.xauth)" If the file mode is more permissive than 0600, this is finding.

Fix: F-31822r1_fix

Change the mode of the .Xauthority files. Procedure: # chmod 0600 .Xauthority

b

.Xauthority or X*.hosts (or equivalent) file(s) must be used to restrict access to the X server.

CM-2 - Medium - CCI-000297 - V-12016 - SV-37684r1_rule

RMF Control

CM-2

Severity

M

CCI

CCI-000297

Version

GEN005220

Vuln IDs

V-12016

Rule IDs

SV-37684r1_rule

If access to the X server is not restricted, a user's X session may be compromised.System AdministratorECCD-1, ECCD-2

Checks: C-36875r1_chk

Determine if the X server is running. Procedure: # ps -ef |grep X Determine if xauth is being used. Procedure: # xauth xauth> list If the above command sequence does not show any host other than the localhost, then xauth is not being used. Search the system for an X*.hosts file, where "*" is a display number used to limit X window connections. If no files are found, X*.hosts files are not being used. If the X*.hosts files contain any unauthorized hosts, this is a finding. If both xauth and X*.hosts files are not being used, this is a finding.

Fix: F-31858r1_fix

Create an X*.hosts file, where "*" is a display number used to limit X window connections. Add the list of authorized X clients to the file.

b

The .Xauthority utility must only permit access to authorized hosts.

AC-6 - Medium - CCI-000225 - V-12017 - SV-37685r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN005240

Vuln IDs

V-12017

Rule IDs

SV-37685r1_rule

If unauthorized clients are permitted access to the X server, a user's X session may be compromised.System AdministratorECCD-1, ECCD-2

Checks: C-36877r1_chk

Check the X window system access is limited to authorized clients. Procedure: # xauth xauth> list Ask the SA if the clients listed are authorized. If any are not, this is a finding.

Fix: F-31867r1_fix

Remove unauthorized clients from the xauth configuration. # xauth remove <display name>

b

X Window System connections not required must be disabled.

AC-17 - Medium - CCI-001436 - V-12018 - SV-37686r1_rule

RMF Control

AC-17

Severity

M

CCI

Version

GEN005260

Vuln IDs

V-12018

Rule IDs

SV-37686r1_rule

If unauthorized clients are permitted access to the X server, a user's X session may be compromised.System AdministratorECSC-1

Checks: C-36878r1_chk

Determine if the X window system is running. Procedure: # ps -ef |grep Xorg Ask the SA if the X window system is an operational requirement. If it is not, this is a finding.

Fix: F-31878r1_fix

Disable the X Windows server on the system.

b

The snmpd.conf file must be owned by root.

AC-6 - Medium - CCI-000225 - V-12019 - SV-37703r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN005360

Vuln IDs

V-12019

Rule IDs

SV-37703r1_rule

The snmpd.conf file contains authenticators and must be protected from unauthorized access and modification. If the file is not owned by root, it may be subject to access and modification from unauthorized users.System AdministratorECLP-1

Checks: C-36896r1_chk

Determine the owner of the SNMP configuration file. Procedure: Find the snmpd.conf file. The default install location is /etc/snmp/snmpd.conf but may be different depending on the SNMP agent installed. # find / -name snmpd.conf # ls -lL <snmpd.conf> If the snmpd.conf file is not owned by root, this is a finding.

Fix: F-32028r1_fix

Change the owner of the snmpd.conf file to root. Procedure: # chown root <snmpd.conf file>

b

The system must not be used as a syslog server (loghost) for systems external to the enclave.

CM-6 - Medium - CCI-000366 - V-12020 - SV-37810r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN005440

Vuln IDs

V-12020

Rule IDs

SV-37810r1_rule

Syslog messages are typically unencrypted, may contain sensitive information, and are restricted to the enclave.System AdministratorECSC-1

Checks: C-37010r1_chk

Ask the SA if the loghost server is collecting data for hosts outside the local enclave. If it is, this is a finding.

Fix: F-32274r1_fix

Configure the hosts outside of the local enclave to not log to this system.

b

The syslog daemon must not accept remote messages unless it is a syslog server documented using site-defined procedures.

CM-6 - Medium - CCI-000366 - V-12021 - SV-37813r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN005480

Vuln IDs

V-12021

Rule IDs

SV-37813r1_rule

Unintentionally running a syslog server accepting remote messages puts the system at increased risk. Malicious syslog messages sent to the server could exploit vulnerabilities in the server software itself, could introduce misleading information in to the system's logs, or could fill the system's storage leading to a Denial of Service.System AdministratorECSC-1

Checks: C-37017r2_chk

Ask the SA if the system is an authorized syslog server. If the system is an authorized syslog server, this is not applicable. Determine if the system's syslog service is configured to accept remote messages. # ps -ef | grep syslogd If the '-r' option is present, the system is configured to accept remote syslog messages, and this is a finding.

Fix: F-32284r1_fix

Edit /etc/sysconfig/syslog to removing the '-r' in SYSLOGD_OPTIONS. Restart the syslogd service.

b

The SSH daemon must be configured for IP filtering.

CM-6 - Medium - CCI-000366 - V-12022 - SV-37913r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN005540

Vuln IDs

V-12022

Rule IDs

SV-37913r1_rule

The SSH daemon must be configured for IP filtering to provide a layered defense against connection attempts from unauthorized addresses.System AdministratorECSC-1

Checks: C-37139r1_chk

Check the TCP wrappers configuration files to determine if sshd is configured to use TCP wrappers. Procedure: # grep sshd /etc/hosts.deny # grep sshd /etc/hosts.allow If no entries are returned, the TCP wrappers are not configured for sshd, this is a finding.

Fix: F-32407r1_fix

Add appropriate IP restrictions for SSH to the /etc/hosts.deny and/or /etc/hosts.allow files.

b

IP forwarding for IPv4 must not be enabled, unless the system is a router.

CM-6 - Medium - CCI-000366 - V-12023 - SV-37929r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN005600

Vuln IDs

V-12023

Rule IDs

SV-37929r1_rule

If the system is configured for IP forwarding and is not a designated router, it could be used to bypass network security by providing a path for communication not filtered by network devices.System AdministratorECSC-1

Checks: C-37179r1_chk

Check if the system is configured for IPv4 forwarding. If the system is a VM host and acts as a router solely for the benefits of its client systems, then this rule is not applicable. Procedure: # cat /proc/sys/net/ipv4/ip_forward If the value is set to "1", IPv4 forwarding is enabled this is a finding.

Fix: F-32422r1_fix

Edit "/etc/sysctl.conf" and set net.ipv4.ip_forward to "0". Restart the system or run "sysctl -p" to make the change take effect.

b

The system must not have a public Instant Messaging (IM) client installed.

CM-6 - Medium - CCI-000366 - V-12024 - SV-37862r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN006000

Vuln IDs

V-12024

Rule IDs

SV-37862r1_rule

Public (IM) systems are not approved for use and may result in the unauthorized distribution of information. IM clients provide a way for a user to send a message to one or more other users in real time. Additional capabilities may include file transfer and support for distributed game playing. Communication between clients and associated directory services are managed through messaging servers. Commercial IM clients include AOL Instant Messenger (AIM), MSN Messenger, and Yahoo! Messenger. IM clients present a security issue when the clients route messages through public servers. The obvious implication is potentially sensitive information could be intercepted or altered in the course of transmission. This same issue is associated with the use of public e-mail servers. In order to reduce the potential for disclosure of sensitive Government information and to ensure the validity of official government information, IM clients connecting to public IM services will not be installed. Clients use to access internal or DoD-controlled IM services are permitted.System AdministratorECIM-1

Checks: C-37073r1_chk

If an IM client is installed, ask the SA if it has access to any public domain IM servers. If it does have access to public servers, this is a finding.

Fix: F-32341r1_fix

Uninstall the IM client from the system, or configure the client to only connect to DoD-approved IM services.

b

The system must not have any peer-to-peer file-sharing application installed.

AC-17 - Medium - CCI-001436 - V-12025 - SV-37865r1_rule

RMF Control

AC-17

Severity

M

CCI

Version

GEN006040

Vuln IDs

V-12025

Rule IDs

SV-37865r1_rule

Peer-to-peer file-sharing software can result in the unintentional exfiltration of information. There are also many legal issues associated with these types of utilities including copyright infringement or other intellectual property issues. The ASD Memo "Use of Peer-to-Peer (P2P) File-Sharing Applications across the DoD" states the following: “P2P file-sharing applications are authorized for use on DOD networks with approval by the appropriate Designated Approval Authority (DAA). Documented requirements, security architecture, configuration management process, and a training program for users are all requirements within the approval process. The unauthorized use of application or services, including P2P applications, is prohibited, and such applications or services must be eliminated.” P2P applications include, but are not limited to, the following: -Napster -Kazaa -ARES -Limewire -IRC Chat Relay -BitTorrentSystem AdministratorDesignated Approving AuthorityECSC-1

Checks: C-37078r1_chk

Ask the SA if any peer-to-peer file-sharing applications are installed. Some examples of these applications include: - Napster - Kazaa - ARES - Limewire - IRC Chat Relay - BitTorrent If any of these applications are installed, this is a finding.

Fix: F-32351r1_fix

Uninstall the peer-to-peer file sharing application(s) from the system.

b

NIS maps must be protected through hard-to-guess domain names.

CM-6 - Medium - CCI-000366 - V-12026 - SV-37743r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN006420

Vuln IDs

V-12026

Rule IDs

SV-37743r1_rule

The use of hard-to-guess NIS domain names provides additional protection from unauthorized access to the NIS directory information.System AdministratorECSC-1

Checks: C-36940r2_chk

Check the domain name for NIS maps. Procedure: # domainname If the name returned is simple to guess, such as the organization name, building or room name, etc., this is a finding. If the system does not use NIS, this is not applicable.

Fix: F-32205r1_fix

Change the NIS domainname to a value difficult to guess. Consult vendor documentation for the required procedure.

b

The system vulnerability assessment tool, host-based intrusion detection tool, and file integrity tool must notify the SA and the IAO of a security breach or a suspected security breach.

CM-6 - Medium - CCI-000366 - V-12028 - SV-37747r2_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN006560

Vuln IDs

V-12028

Rule IDs

SV-37747r2_rule

Timely notifications of potential security compromises minimize the potential damage. Minimally, the system must log these events, and the SA and the ISSO will receive the notifications during the daily system log review. If feasible, active alerting (such as e-mail or paging) should be employed consistent with the site's established operations management systems and procedures.System AdministratorInformation Assurance Officer

Checks: C-36944r1_chk

For each security tool on the system, determine if the tool is configured to notify the IAO and SA of any detected security problem. If such notifications are not configured, this is a finding.

Fix: F-32209r1_fix

Configure the security tools on the system to notify the IAO and SA when any security issues are detected.

b

The system's access control program must be configured to grant or deny system access to specific hosts.

CM-6 - Medium - CCI-000366 - V-12030 - SV-37758r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN006620

Vuln IDs

V-12030

Rule IDs

SV-37758r1_rule

If the system's access control program is not configured with appropriate rules for allowing and denying access to system network resources, services may be accessible to unauthorized hosts.System AdministratorECSC-1

Checks: C-36955r1_chk

Check for the existence of the "/etc/hosts.allow" and "/etc/hosts.deny" files. Procedure: # ls -la /etc/hosts.allow # ls -la /etc/hosts.deny If either file does not exist, this is a finding. Check for the presence of a "default deny" entry. Procedure: # grep "ALL: ALL" /etc/hosts.deny If the "ALL: ALL" entry is not present the "/etc/hosts.deny" file, any TCP service from a host or network not matching other rules will be allowed access. If the entry is not in "/etc/hosts.deny", this is a finding.

Fix: F-32220r1_fix

Edit the "/etc/hosts.all" and "/etc/hosts.deny" files to configure access restrictions.

b

The /etc/securetty file must be group-owned by root, sys, or bin.

AC-6 - Medium - CCI-000225 - V-12038 - SV-37340r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN000000-LNX00620

Vuln IDs

V-12038

Rule IDs

SV-37340r1_rule

The securetty file contains the list of terminals permitting direct root logins. It must be protected from unauthorized modification.System AdministratorECLP-1

Checks: C-8001r2_chk

Check /etc/securetty group ownership: # ls -lL /etc/securetty If /etc/securetty is not group owned by root, sys, or bin, then this is a finding.

Fix: F-11295r2_fix

Change the group-owner of /etc/securetty to root, sys, or bin. Example: # chgrp root /etc/securetty

b

The /etc/securetty file must be owned by root.

AC-6 - Medium - CCI-000225 - V-12039 - SV-37341r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN000000-LNX00640

Vuln IDs

V-12039

Rule IDs

SV-37341r1_rule

The securetty file contains the list of terminals permitting direct root logins. It must be protected from unauthorized modification.System AdministratorECLP-1

Checks: C-8002r2_chk

Check /etc/securetty ownership. Procedure: # ls -lL /etc/securetty If /etc/securetty is not owned by root, this is a finding.

Fix: F-11296r2_fix

Change the owner of the /etc/securetty file to root. Procedure: # chown root /etc/securetty

b

The /etc/securetty file must have mode 0600 or less permissive.

AC-6 - Medium - CCI-000225 - V-12040 - SV-37342r3_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN000000-LNX00660

Vuln IDs

V-12040

Rule IDs

SV-37342r3_rule

The securetty file contains the list of terminals permitting direct root logins. It must be protected from unauthorized modification.System Administrator

Checks: C-36031r3_chk

Check /etc/securetty permissions. Procedure: # ls -lL /etc/securetty If /etc/securetty has a mode more permissive than 0600, this is a finding.

Fix: F-31277r3_fix

Change the mode of the /etc/securetty file to 0600. Procedure: # chmod 0600 /etc/securetty

b

Network analysis tools must not be installed.

CM-2 - Medium - CCI-000305 - V-12049 - SV-37446r2_rule

RMF Control

CM-2

Severity

M

CCI

Version

GEN003865

Vuln IDs

V-12049

Rule IDs

SV-37446r2_rule

Network analysis tools allow for the capture of network traffic visible to the system. If the system is being used as a network analysis/troubleshooting system then these tools are allowed if documented.System Administrator

Checks: C-36118r2_chk

Determine if any network analysis tools are installed. Procedure: # find / -name ethereal # find / -name wireshark # find / -name tshark # find / -name nc # find / -name tcpdump # find / -name snoop If any network analysis tools are found, this is a finding

Fix: F-31364r2_fix

Remove each network analysis tool binary from the system. Remove package items with a package manager, others remove the binary directly. Procedure: Find the binary file: # find / -name <Item to be removed> Find the package, if any, to which it belongs: # rpm -qf <binary file> Remove the package if it does not also include other software: # rpm -e <package name> or # yum remove <package name> If the item to be removed is not in a package, or the entire package cannot be removed because of other software it provides, remove the item's binary file. # rm <binary file>

b

The system must use and update a DoD-approved virus scan program.

SI-3 - Medium - CCI-001668 - V-12765 - SV-37760r2_rule

RMF Control

SI-3

Severity

M

CCI

CCI-001668

Version

GEN006640

Vuln IDs

V-12765

Rule IDs

SV-37760r2_rule

Virus scanning software can be used to protect a system from penetration from computer viruses and to limit their spread through intermediate systems. The virus scanning software should be configured to perform scans dynamically on accessed files. If this capability is not available, the system must be configured to scan, at a minimum, all altered files on the system on a daily basis. If the system processes inbound SMTP mail, the virus scanner must be configured to scan all received mail.System Administrator

Checks: C-36956r2_chk

Check for the existence of a cron job to execute a DoD-approved command-line scan tool daily. Other tools may be available but will have to be manually reviewed if they are installed. In addition, the definitions files should not be older than 7 days. Check if DoD-approved command-line scan tool is scheduled to run: # grep [scan tool] /var/spool/cron/* /etc/cron.d/* /etc/cron.daily/* /etc/cron.hourly/* /etc/cron.monthly/* /etc/cron.weekly/* If a virus scanner is not being run daily and an exception has not been documented with the IAO, this is a finding. Perform the following command to ensure the virus definition signature files are not older than 7 days. # cd <scan tool install directory> # ls -la *.dat If the virus definitions are older than 7 days, this is a finding.

Fix: F-32221r2_fix

Install a DoD-approved command-line virus scan tool, or an appropriate alternative. Ensure the virus signature definition files are no older than 7 days. Configure the system to run a virus scan on altered files dynamically or daily. If daily scans impede operations, justify, document, and obtain IAO approval for alternate scheduling.

b

The system clock must be synchronized continuously.

CM-6 - Medium - CCI-000366 - V-22290 - SV-26292r4_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN000241

Vuln IDs

V-22290

Rule IDs

SV-26292r4_rule

A synchronized system clock is critical for the enforcement of time-based policies and the correlation of logs and audit records with other systems. Internal system clocks tend to drift and require periodic resynchronization to ensure their accuracy. Software, such as ntpd, can be used to continuously synchronize the system clock with authoritative sources. Alternatively, the system may be synchronized periodically, with a maximum of one day between synchronizations. If the system is completely isolated (i.e., it has no connections to networks or other systems), time synchronization is not required as no correlation of events or operation of time-dependent protocols between systems will be necessary. If the system is completely isolated, this requirement is not applicable.System Administrator

Checks: C-27388r7_chk

Check to see if ntp is running in continuous mode. # ps -ax | grep ntp If the process is found, then check the ntp.conf file for the maxpoll option setting. # grep maxpoll /etc/ntp.conf If the option is set to 17 or is not set, this is a finding.

Fix: F-23444r3_fix

Enable the NTP daemon for continuous synchronization. # service ntpd start ; chkconfig ntpd on Edit the "/etc/ntp.conf" file and add or update an entry to define "maxpoll" to "10".

b

The system must use at least two time sources for clock synchronization.

AU-8 - Medium - CCI-000160 - V-22291 - SV-37412r1_rule

RMF Control

AU-8

Severity

M

CCI

CCI-000160

Version

GEN000242

Vuln IDs

V-22291

Rule IDs

SV-37412r1_rule

A synchronized system clock is critical for the enforcement of time-based policies and the correlation of logs and audit records with other systems. For redundancy, two time sources are required so synchronization continues to function if one source fails. If the system is completely isolated (i.e., it has no connections to networks or other systems), time synchronization is not required as no correlation of events or operation of time-dependent protocols between systems will be necessary. If the system is completely isolated, this requirement is not applicable. Note: For the network time protocol (NTP), the requirement is two servers, but it is recommended to configure at least four distinct time servers which allow NTP to effectively exclude a time source not consistent with the others. The system's local clock must be excluded from the count of time sources.System AdministratorECSC-1

Checks: C-36095r1_chk

Check the root crontab (crontab -l) and the global crontabs in /etc/crontab, /etc/cron.d/*, or scripts in the /etc/cron.daily directory for the presence of an "ntpd -qg" job. If the "ntpd -qg" command is not invoked with at least two external NTP servers listed, this is a finding. Check the NTP daemon configuration for at least two external servers. # grep ^server /etc/ntp.conf | egrep -v '(127.127.1.0|127.127.1.1)' If less than two servers or external reference clocks (127.127.x.x other than 127.127.1.0 or 127.127.1.1) are listed, this is a finding.

Fix: F-31342r1_fix

If using "ntpd -qg", add additional NTP servers to the cron job running "ntpd -qg". If using the NTP daemon, add an additional "server" line to /etc/ntp.conf for each additional NTP server.

a

The system must use time sources local to the enclave.

AU-8 - Low - CCI-000160 - V-22292 - SV-37413r2_rule

RMF Control

AU-8

Severity

L

CCI

CCI-000160

Version

GEN000244

Vuln IDs

V-22292

Rule IDs

SV-37413r2_rule

A synchronized system clock is critical for the enforcement of time-based policies and the correlation of logs and audit records with other systems. The network architecture should provide multiple time servers within an enclave providing local service to the enclave and synchronize with time sources outside of the enclave. If this server is an enclave time server, this requirement is not applicable. If the system is completely isolated (i.e., it has no connections to networks or other systems), time synchronization is not required as no correlation of events or operation of time-dependent protocols between systems will be necessary. If the system is completely isolated, this requirement is not applicable.System Administrator

Checks: C-36096r1_chk

Check the root crontab (crontab -l) and the global crontabs in /etc/crontab, /etc/cron.d/*, or scripts in the /etc/cron.daily directory for the presence of an "ntpd -qg" job. If the "ntpd -qg" command is invoked with NTP servers outside of the enclave, this is a finding. Check the NTP daemon configuration for NTP servers. # grep ^server /etc/ntp.conf | grep -v 127.127.1.1 If an NTP server is listed outside of the enclave, this is a finding.

Fix: F-31343r1_fix

If using "ntpd -qg", remove NTP servers external to the enclave from the cron job running "ntpd -qg". If using the NTP daemon, remove the "server" line from /etc/ntp.conf for each NTP server external to the enclave.

b

The time synchronization configuration file (such as /etc/ntp.conf) must be owned by root.

AC-6 - Medium - CCI-000225 - V-22294 - SV-37415r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN000250

Vuln IDs

V-22294

Rule IDs

SV-37415r1_rule

A synchronized system clock is critical for the enforcement of time-based policies and the correlation of logs and audit records with other systems. If an illicit time source is used for synchronization, the integrity of system logs and the security of the system could be compromised. If the configuration files controlling time synchronization are not owned by a system account, unauthorized modifications could result in the failure of time synchronization.System AdministratorECLP-1

Checks: C-36098r1_chk

Check the ownership of the NTP configuration file. # ls -l /etc/ntp.conf If the owner is not root, this is a finding.

Fix: F-31345r1_fix

Change the owner of the NTP configuration file. # chown root /etc/ntp.conf

b

The time synchronization configuration file (such as /etc/ntp.conf) must be group-owned by root, bin, or sys.

AC-6 - Medium - CCI-000225 - V-22295 - SV-37416r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN000251

Vuln IDs

V-22295

Rule IDs

SV-37416r1_rule

A synchronized system clock is critical for the enforcement of time-based policies and the correlation of logs and audit records with other systems. If an illicit time source is used for synchronization, the integrity of system logs and the security of the system could be compromised. If the configuration files controlling time synchronization are not owned by a system group, unauthorized modifications could result in the failure of time synchronization.System AdministratorECLP-1

Checks: C-36099r2_chk

Check the group ownership of the NTP configuration file. Procedure: # ls -lL /etc/ntp.conf If the group owner is not root, bin, or sys, this is a finding.

Fix: F-31346r1_fix

Change the group-owner of the NTP configuration file. Procedure: # chgrp root /etc/ntp.conf

b

The time synchronization configuration file (such as /etc/ntp.conf) must have mode 0640 or less permissive.

AC-6 - Medium - CCI-000225 - V-22296 - SV-37417r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN000252

Vuln IDs

V-22296

Rule IDs

SV-37417r1_rule

A synchronized system clock is critical for the enforcement of time-based policies and the correlation of logs and audit records with other systems. If an illicit time source is used for synchronization, the integrity of system logs and the security of the system could be compromised. If the configuration files controlling time synchronization are not protected, unauthorized modifications could result in the failure of time synchronization.System AdministratorECLP-1

Checks: C-36100r1_chk

Check the mode for the NTP configuration file is not more permissive than 0640. # ls -l /etc/ntp.conf If the mode is more permissive than 0640, this is a finding.

Fix: F-31347r1_fix

Change the mode of the NTP configuration file to 0640 or more restrictive. # chmod 0640 /etc/ntp.conf

b

The time synchronization configuration file (such as /etc/ntp.conf) must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22297 - SV-37418r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN000253

Vuln IDs

V-22297

Rule IDs

SV-37418r1_rule

A synchronized system clock is critical for the enforcement of time-based policies and the correlation of logs and audit records with other systems. If an illicit time source is used for synchronization, the integrity of system logs and the security of the system could be compromised. If the configuration files controlling time synchronization are not protected, unauthorized modifications could result in the failure of time synchronization.System AdministratorECLP-1

Checks: C-36101r1_chk

Check the NTP configuration file has no extended ACL. # ls -l /etc/ntp.conf If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-23451r1_fix

Remove the extended ACL from the NTP configuration file. # setfacl --remove-all /etc/ntp.conf

a

The system must limit users to 10 simultaneous system logins, or a site-defined number, in accordance with operational requirements.

AC-10 - Low - CCI-000054 - V-22298 - SV-37182r1_rule

RMF Control

AC-10

Severity

L

CCI

CCI-000054

Version

GEN000450

Vuln IDs

V-22298

Rule IDs

SV-37182r1_rule

Limiting simultaneous user logins can insulate the system from denial of service problems caused by excessive logins. Automated login processes operating improperly or maliciously may result in an exceptional number of simultaneous login sessions. If the defined value of 10 logins does not meet operational requirements, the site may define the permitted number of simultaneous login sessions based on operational requirements. This limit is for the number of simultaneous login sessions for EACH user account. This is NOT a limit on the total number of simultaneous login sessions on the system.trueSystem AdministratorECSC-1

Checks: C-35885r1_chk

Check for a default maxlogins line in the /etc/security/limits.conf and /etc/security/limits.d/* files. Procedure: #grep maxlogins /etc/security/limits.conf /etc/security/limits.d/* The default maxlimits should be set to a max of 10 or a documented site defined number: * - maxlogins 10 If no such line exists, this is a finding.

Fix: F-31140r1_fix

Add a "maxlogins" line such as "* hard maxlogins 10" to /etc/security/limits.conf or a file in /etc/security/limits.d. The enforced maximum should be defined by site requirements and policy.

a

The system must display the date and time of the last successful account login upon login.

AC-9 - Low - CCI-000052 - V-22299 - SV-37187r1_rule

RMF Control

AC-9

Severity

L

CCI

CCI-000052

Version

GEN000452

Vuln IDs

V-22299

Rule IDs

SV-37187r1_rule

Providing users with feedback on when account accesses last occurred facilitates user recognition and reporting of unauthorized account use.System AdministratorECSC-1

Checks: C-35888r2_chk

Check that pam_lastlog is used and not silent, or that the SSH daemon is configured to display last login information. # grep pam_lastlog /etc/pam.d/sshd If pam_lastlog is present, and does not have the "silent" option, this is not a finding. # grep -i PrintLastLog /etc/ssh/sshd_config If PrintLastLog is not present in the configuration, this is not a finding. This is the default setting. If PrintLastLog is present in the configuration and set to "yes" (case insensitive), this is not a finding. Otherwise, this is a finding.

Fix: F-31144r1_fix

Implement pam_lastlog, or enable PrintLastLog in the SSH daemon. To enable pam_lastlog, add a line such as "session required pam_lastlog.so" to /etc/pam.d/sshd. To enable PrintLastLog in the SSH daemon, remove any lines disabling this option from /etc/ssh/sshd_config.

a

The system must display a publicly-viewable pattern during a graphical desktop environment session lock.

AC-14 - Low - CCI-000061 - V-22301 - SV-37222r1_rule

RMF Control

AC-14

Severity

L

CCI

CCI-000061

Version

GEN000510

Vuln IDs

V-22301

Rule IDs

SV-37222r1_rule

To protect the on-screen content of a session, it must be replaced with a publicly-viewable pattern upon session lock. Examples of publicly viewable patterns include screen saver patterns, photographic images, solid colors, or a blank screen, so long as none of those patterns convey sensitive information. This requirement applies to graphical desktop environments provided by the system to locally attached displays and input devices, as well as, to graphical desktop environments provided to remote systems using remote access protocols.System AdministratorPESL-1

Checks: C-35911r1_chk

Determine if a publicly-viewable pattern is displayed during a session lock. Some screensaver themes available but not included in the RHEL distribution use a snapshot of the current screen as a graphic. This theme does not qualify as a publicly-viewable pattern. If the session lock pattern is not publicly-viewable this is a finding.

Fix: F-31169r1_fix

Configure the system to display a publicly-viewable pattern during a session lock. This is done graphically by selecting a screensaver theme using gnome-screensaver-preferences command. Any of the themes distributed with RHEL may be used including "Blank Screen".

b

The system must enforce compliance of the entire password during authentification.

IA-5 - Medium - CCI-000205 - V-22302 - SV-37261r2_rule

RMF Control

IA-5

Severity

M

CCI

CCI-000205

Version

GEN000585

Vuln IDs

V-22302

Rule IDs

SV-37261r2_rule

Some common password hashing schemes only process the first eight characters of a user's password, which reduces the effective strength of the password.System Administrator

Checks: C-35951r3_chk

Verify no valid password hash in /etc/passwd or /etc/shadow begins with a character other than an underscore (_) or dollar sign ($). # cut -d ':' -f2 /etc/passwd # cut -d ':' -f2 /etc/shadow If any valid password hash is present that does not have an initial underscore (_) or dollar sign ($) character, this is a finding. Note: Locked accounts are indicated by a leading exclamation point (!). System accounts, other than "root", may have an asterisk (*) in the password field. On systems utilizing shadow passwords, the password field in /etc/passwd will be a single "x".

Fix: F-31207r1_fix

Change the passwords for all accounts using non-compliant password hashes. (This requires GEN000590 is already met.)

b

The system must use a FIPS 140-2 approved cryptographic hashing algorithm for generating account password hashes.

IA-7 - Medium - CCI-000803 - V-22303 - SV-26313r2_rule

RMF Control

IA-7

Severity

M

CCI

CCI-000803

Version

GEN000590

Vuln IDs

V-22303

Rule IDs

SV-26313r2_rule

Systems must employ cryptographic hashes for passwords using the SHA-2 family of algorithms or FIPS 140-2 approved successors. The use of unapproved algorithms may result in weak password hashes more vulnerable to compromise.System Administrator

Checks: C-35959r2_chk

Verify the algorithm used for password hashing is of the SHA-2 family. # egrep "password .* pam_unix.so" /etc/pam.d/system-auth-ac # egrep "ENCRYPT_METHOD" /etc/login.defs # egrep "crypt_style" /etc/libuser.conf If any output indicates the hash algorithm is not set to sha256 or sha512, this is a finding.

Fix: F-31215r2_fix

Change the default password algorithm. # authconfig --passalgo=sha512 --update NOTE: Executing the above command will also update the required parameters in /etc/login.defs and /etc/libuser.conf

b

The password hashes stored on the system must have been generated using a FIPS 140-2 approved cryptographic hashing algorithm.

IA-5 - Medium - CCI-000196 - V-22304 - SV-26316r2_rule

RMF Control

IA-5

Severity

M

CCI

CCI-000196

Version

GEN000595

Vuln IDs

V-22304

Rule IDs

SV-26316r2_rule

Systems must employ cryptographic hashes for passwords using the SHA-2 family of algorithms or FIPS 140-2 approved successors. The use of unapproved algorithms may result in weak password hashes more vulnerable to compromise.System AdministratorDCNR-1, IAIA-1, IAIA-2

Checks: C-35965r2_chk

Check all password hashes in /etc/passwd or /etc/shadow begin with '$5$' or '$6$'. Procedure: # cut -d ':' -f2 /etc/passwd # cut -d ':' -f2 /etc/shadow Any password hashes present not beginning with '$5$' or, '$6$' is a finding. Any entries showing only NP, LK, or x are not findings.

Fix: F-31221r1_fix

Change the passwords for all accounts using non-compliant password hashes. (This requires GEN000590 is already met.)

b

The system must require passwords contain at least one lowercase alphabetic character.

IA-5 - Medium - CCI-000193 - V-22305 - SV-26321r1_rule

RMF Control

IA-5

Severity

M

CCI

CCI-000193

Version

GEN000610

Vuln IDs

V-22305

Rule IDs

SV-26321r1_rule

To enforce the use of complex passwords, minimum numbers of characters of different classes are mandated. The use of complex passwords reduces the ability of attackers to successfully obtain valid passwords using guessing or exhaustive search techniques. Complexity requirements increase the password search space by requiring users to construct passwords from a larger character set than they may otherwise use.System AdministratorIAIA-1, IAIA-2

Checks: C-35977r1_chk

Check /etc/pam.d/system-auth for lcredit setting. Procedure: Check the password lcredit option # grep pam_cracklib.so /etc/pam.d/system-auth Confirm the lcredit option is set to -1 as in the example: password required pam_cracklib.so lcredit=-1 There may be other options on the line. If no such line is found, or the lcredit is not -1 this is a finding.

Fix: F-31231r1_fix

Edit "/etc/pam.d/system-auth" to include the line: password required pam_cracklib.so lcredit=-1 prior to the "password include system-auth-ac" line.

b

The system must require at least eight characters be changed between the old and new passwords during a password change.

IA-5 - Medium - CCI-000195 - V-22306 - SV-37304r2_rule

RMF Control

IA-5

Severity

M

CCI

CCI-000195

Version

GEN000750

Vuln IDs

V-22306

Rule IDs

SV-37304r2_rule

To ensure password changes are effective in their goals, the system must ensure that old and new passwords have significant differences. Without significant changes, new passwords may be easily guessed based on the value of a previously compromised password.System Administrator

Checks: C-35999r3_chk

Check /etc/pam.d/system-auth for a pam_cracklib parameter difok. Procedure: # grep difok /etc/pam.d/system-auth If difok is not present, or has a value less than 8, this is a finding. Check for system-auth-ac inclusions. # grep -c system-auth-ac /etc/pam.d/* If the system-auth-ac file is included anywhere # more /etc/pam.d/system-auth-ac | grep difok If system-auth-ac is included anywhere and difok is not present, or has a value less than 8, this is a finding. Ensure the passwd command uses the system-auth settings. # grep system-auth /etc/pam.d/passwd If a line "password include system-auth" is not found then the password checks in system-auth will not be applied to new passwords and this is a finding.

Fix: F-31252r2_fix

If /etc/pam.d/system-auth references /etc/pam.d/system-auth-ac refer to the man page for system-auth-ac for a description of how to add options not configurable with authconfig. Edit /etc/pam.d/system-auth and add or edit a pam_cracklib entry with an difok parameter set equal to or greater than 8.

b

The system must prevent the use of dictionary words for passwords.

IA-5 - Medium - CCI-000189 - V-22307 - SV-37318r1_rule

RMF Control

IA-5

Severity

M

CCI

CCI-000189

Version

GEN000790

Vuln IDs

V-22307

Rule IDs

SV-37318r1_rule

An easily guessable password provides an open door to any external or internal malicious intruder. Many computer compromises occur as the result of account name and password guessing. This is generally done by someone with an automated script that uses repeated logon attempts until the correct account and password pair is guessed. Utilities, such as cracklib, can be used to validate passwords are not dictionary words and meet other criteria during password changes.System AdministratorIAIA-1, IAIA-2

Checks: C-36011r1_chk

Check /etc/pam.d/system-auth for pam_cracklib configuration. Procedure: # grep pam_cracklib /etc/pam.d/system-auth* If pam_cracklib is not present. This is a finding. If pam_cracklib is present only in /etc/pam.d/system-auth-ac: ensure that /etc/pam.d/system-auth includes /etc/pam.d/system-auth-ac. #grep system-auth-ac /etc/pam.d/system-auth This should return: auth include system-auth-ac account include system-auth-ac password include system-auth-ac session include system-auth-ac /etc/pam.d/system-auth-ac should only be included by /etc/pam.d/system-auth. All other pam files should include /etc/pam.d/system-auth. If pam_cracklib is not defined in /etc/pam.d/system-auth either directly or through inclusion of system-auth-ac, this is a finding. Ensure the passwd command uses the system-auth settings. # grep system-auth /etc/pam.d/passwd If a line "password include system-auth" is not found then the password checks in system-auth will not be applied to new passwords, this is a finding.

Fix: F-31262r1_fix

If /etc/pam.d/system-auth references /etc/pam.d/system-auth-ac refer to the man page for system-auth-ac for a description of how to add options not configurable with authconfig. Edit /etc/pam.d/system-auth and configure pam_cracklib by adding a line such as "password required pam_cracklib.so"

a

The system must restrict the ability to switch to the root user to members of a defined group.

AC-2 - Low - CCI-000009 - V-22308 - SV-37345r1_rule

RMF Control

AC-2

Severity

L

CCI

CCI-000009

Version

GEN000850

Vuln IDs

V-22308

Rule IDs

SV-37345r1_rule

Configuring a supplemental group for users permitted to switch to the root user prevents unauthorized users from accessing the root account, even with knowledge of the root credentials.System AdministratorECLP-1

Checks: C-27453r1_chk

Check /etc/pam.d/su uses pam_wheel. # grep pam_wheel /etc/pam.d/su If pam_wheel is not present, or is commented out, this is a finding.

Fix: F-31282r1_fix

Edit /etc/pam.d/su and uncomment or add a line such as "auth required pam_wheel.so". If necessary, create a "wheel" group and add administrative users to the group.

b

The root account's home directory must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22309 - SV-37358r2_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN000930

Vuln IDs

V-22309

Rule IDs

SV-37358r2_rule

File system extended ACLs provide access to files beyond what is allowed by the unix permissions of the files.System Administrator

Checks: C-36046r2_chk

Check the root account's home directory has no extended ACL. # find ~root -type d -prune -exec ls -ld {} \; If the permissions include a '+' the directory has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-31290r1_fix

Remove the extended ACL from the root account's home directory. # setfacl --remove-all <root home directory>

b

The root account's library search path must be the system default and must contain only absolute paths.

CM-6 - Medium - CCI-000366 - V-22310 - SV-37363r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN000945

Vuln IDs

V-22310

Rule IDs

SV-37363r1_rule

The library search path environment variable(s) contain a list of directories for the dynamic linker to search to find libraries. If this path includes the current working directory or other relative paths, libraries in these directories may be loaded instead of system libraries. This variable is formatted as a colon-separated list of directories. If there is an empty entry, such as a leading or trailing colon or two consecutive colons, this is interpreted as the current working directory. Entries starting with a slash (/) are absolute paths.System AdministratorECSC-1

Checks: C-36052r1_chk

Check the LD_LIBRARY_PATH environment variable is empty or not defined for the root user. # echo $LD_LIBRARY_PATH If a path list is returned, this is a finding.

Fix: F-31296r1_fix

Edit the root user initialization files and remove any definition of LD_LIBRARY_PATH.

b

The root account's list of preloaded libraries must be empty.

CM-6 - Medium - CCI-000366 - V-22311 - SV-37364r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN000950

Vuln IDs

V-22311

Rule IDs

SV-37364r1_rule

The library preload list environment variable contains a list of libraries for the dynamic linker to load before loading the libraries required by the binary. If this list contains paths to libraries relative to the current working directory, unintended libraries may be preloaded. This variable is formatted as a space-separated list of libraries. Paths starting with (/) are absolute paths.System AdministratorECSC-1

Checks: C-36054r1_chk

Check the LD_PRELOAD environment variable is empty or not defined for the root user. # echo $LD_PRELOAD If a path list is returned, this is a finding.

Fix: F-31298r1_fix

Edit the root user initialization files and remove any definition of LD_PRELOAD.

b

All files and directories must have a valid group-owner.

CM-6 - Medium - CCI-000366 - V-22312 - SV-37165r2_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN001170

Vuln IDs

V-22312

Rule IDs

SV-37165r2_rule

Files without a valid group owner may be unintentionally inherited if a group is assigned the same GID as the GID of the files without a valid group-owner.System Administrator

Checks: C-35872r2_chk

Search the system for files without a valid group-owner. # find / -ignore_readdir_race -nogroup If any files are found, this is a finding.

Fix: F-31126r1_fix

Change the group-owner for each file without a valid group-owner. # chgrp avalidgroup /tmp/a-file-without-a-valid-group-owner

b

All network services daemon files must not have extended ACLs.

AC-6 - Medium - CCI-000225 - V-22313 - SV-37199r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001190

Vuln IDs

V-22313

Rule IDs

SV-37199r1_rule

Restricting permission on daemons will protect them from unauthorized modification and possible system compromise.System AdministratorECLP-1

Checks: C-35893r2_chk

Check network services daemon files have no extended ACLs. # ls -la /usr/sbin If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding. Note: Network daemons not residing in these directories must also be checked.

Fix: F-23542r1_fix

Remove the extended ACL from the file. # setfacl --remove-all /usr/sbin/*

b

All system command files must not have extended ACLs.

CM-5 - Medium - CCI-001499 - V-22314 - SV-37210r1_rule

RMF Control

CM-5

Severity

M

CCI

Version

GEN001210

Vuln IDs

V-22314

Rule IDs

SV-37210r1_rule

Restricting permissions will protect system command files from unauthorized modification. System command files include files present in directories used by the operating system for storing default system executables and files present in directories included in the system's default executable search paths.System AdministratorECLP-1

Checks: C-35901r1_chk

Check all system command files have no extended ACLs. # ls -lL /etc /bin /usr/bin /usr/lbin /usr/usb /sbin /usr/sbin If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-31159r1_fix

Remove the extended ACL from the file. # setfacl --remove-all [file with extended ACL]

b

System log files must not have extended ACLs, except as needed to support authorized software.

SI-11 - Medium - CCI-001314 - V-22315 - SV-37233r1_rule

RMF Control

SI-11

Severity

M

CCI

CCI-001314

Version

GEN001270

Vuln IDs

V-22315

Rule IDs

SV-37233r1_rule

If the system log files are not protected, unauthorized users could change the logged data, eliminating its forensic value. Authorized software may be given log file access through the use of extended ACLs when needed and configured to provide the least privileges required.trueSystem AdministratorECLP-1, ECTP-1

Checks: C-35922r1_chk

Verify system log files have no extended ACLs. Procedure: # ls -lL /var/log If the permissions include a '+', the file has an extended ACL. If an extended ACL exists, verify with the SA if the ACL is required to support authorized software and provides the minimum necessary permissions. If an extended ACL exists providing access beyond the needs of authorized software, this is a finding.

Fix: F-31180r1_fix

Remove the extended ACL from the file. Procedure: # setfacl --remove-all [file with extended ACL]

a

All manual page files must not have extended ACLs.

AC-6 - Low - CCI-000225 - V-22316 - SV-37238r2_rule

RMF Control

AC-6

Severity

L

CCI

Version

GEN001290

Vuln IDs

V-22316

Rule IDs

SV-37238r2_rule

If manual pages are compromised, misleading information could be inserted, causing actions to compromise the system.System Administrator

Checks: C-35929r2_chk

Verify all manual page files have no extended ACLs. # ls -lLR /usr/share/man /usr/share/info /usr/share/infopage If the permissions include a '+', the file has an extended ACL this is a finding.

Fix: F-31185r1_fix

Remove the extended ACL from the file. # setfacl --remove-all /usr/share/man/* /usr/share/info/* /usr/share/infopage/*

b

All library files must not have extended ACLs.

CM-5 - Medium - CCI-001499 - V-22317 - SV-37250r2_rule

RMF Control

CM-5

Severity

M

CCI

Version

GEN001310

Vuln IDs

V-22317

Rule IDs

SV-37250r2_rule

Unauthorized access could destroy the integrity of the library files.System Administrator

Checks: C-35940r3_chk

Verify system libraries have no extended ACLs. # ls -lLR /usr/lib/ /lib/ /usr/lib64 /lib64 | grep "+ " If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and has not been approved by the IAO, this is a finding.

Fix: F-31197r1_fix

Remove the extended ACL from the file. # setfacl --remove-all /usr/lib/* /lib/*

b

NIS/NIS+/yp command files must not have extended ACLs.

AC-6 - Medium - CCI-000225 - V-22318 - SV-37277r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001361

Vuln IDs

V-22318

Rule IDs

SV-37277r1_rule

NIS/NIS+/yp files are part of the system's identification and authentication processes and are critical to system security. ACLs on these files could result in unauthorized modification, which could compromise these processes and the system. System AdministratorECLP-1

Checks: C-35968r1_chk

Verify NIS/NIS+/yp files have no extended ACLs. # ls -lL /var/yp/* If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-23574r1_fix

Remove the extended ACL from the file. # setfacl --remove-all /var/yp/*

b

The /etc/resolv.conf file must be owned by root.

AC-6 - Medium - CCI-000225 - V-22319 - SV-37280r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001362

Vuln IDs

V-22319

Rule IDs

SV-37280r1_rule

The resolv.conf (or equivalent) file configures the system's DNS resolver. DNS is used to resolve host names to IP addresses. If DNS configuration is modified maliciously, host name resolution may fail or return incorrect information. DNS may be used by a variety of system security functions such as time synchronization, centralized authentication, and remote system logging. System AdministratorECLP-1

Checks: C-35971r1_chk

Verify the /etc/resolv.conf file is owned by root. # ls -l /etc/resolv.conf If the file is not owned by root, this is a finding.

Fix: F-31226r1_fix

Change the owner of the /etc/resolv.conf file to root. # chown root /etc/resolv.conf

b

The /etc/resolv.conf file must be group-owned by root, bin, or sys.

AC-6 - Medium - CCI-000225 - V-22320 - SV-37286r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001363

Vuln IDs

V-22320

Rule IDs

SV-37286r1_rule

The resolv.conf (or equivalent) file configures the system's DNS resolver. DNS is used to resolve host names to IP addresses. If DNS configuration is modified maliciously, host name resolution may fail or return incorrect information. DNS may be used by a variety of system security functions such as time synchronization, centralized authentication, and remote system logging.System AdministratorECLP-1

Checks: C-35978r2_chk

Check the group ownership of the resolv.conf file. Procedure: # ls -lL /etc/resolv.conf If the file is not group-owned by root, bin, or sys, this is a finding.

Fix: F-31233r2_fix

Change the group-owner of the /etc/resolv.conf file to root, bin, or sys. Procedure: # chgrp root /etc/resolv.conf

b

The /etc/resolv.conf file must have mode 0644 or less permissive.

AC-6 - Medium - CCI-000225 - V-22321 - SV-37291r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001364

Vuln IDs

V-22321

Rule IDs

SV-37291r1_rule

The resolv.conf (or equivalent) file configures the system's DNS resolver. DNS is used to resolve host names to IP addresses. If DNS configuration is modified maliciously, host name resolution may fail or return incorrect information. DNS may be used by a variety of system security functions such as time synchronization, centralized authentication, and remote system logging.System AdministratorECLP-1

Checks: C-35980r1_chk

Check the mode of the /etc/resolv.conf file. # ls -l /etc/resolv.conf If the file mode is not 0644, this is a finding.

Fix: F-31239r1_fix

Change the mode of the /etc/resolv.conf file to 0644. # chmod 0644 /etc/resolv.conf

b

The /etc/resolv.conf file must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22322 - SV-37307r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001365

Vuln IDs

V-22322

Rule IDs

SV-37307r1_rule

The resolv.conf (or equivalent) file configures the system's DNS resolver. DNS is used to resolve host names to IP addresses. If DNS configuration is modified maliciously, host name resolution may fail or return incorrect information. DNS may be used by a variety of system security functions such as time synchronization, centralized authentication, and remote system logging.System AdministratorECLP-1

Checks: C-36001r1_chk

Verify /etc/resolv.conf has no extended ACL. # ls -l /etc/resolv.conf If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-23589r1_fix

Remove the extended ACL from the file. # setfacl --remove-all /etc/resolv.conf

b

The /etc/hosts file must be owned by root.

AC-6 - Medium - CCI-000225 - V-22323 - SV-37309r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001366

Vuln IDs

V-22323

Rule IDs

SV-37309r1_rule

The /etc/hosts file (or equivalent) configures local host name to IP address mappings that typically take precedence over DNS resolution. If this file is maliciously modified, it could cause the failure or compromise of security functions requiring name resolution, which may include time synchronization, centralized authentication, and remote system logging.System AdministratorECLP-1

Checks: C-36003r1_chk

Verify the /etc/hosts file is owned by root. # ls -l /etc/hosts If the file is not owned by root, this is a finding.

Fix: F-31256r1_fix

Change the owner of the /etc/hosts file to root. # chown root /etc/hosts

b

The /etc/hosts file must be group-owned by root, bin, or sys.

AC-6 - Medium - CCI-000225 - V-22324 - SV-37315r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001367

Vuln IDs

V-22324

Rule IDs

SV-37315r1_rule

The /etc/hosts file (or equivalent) configures local host name to IP address mappings that typically take precedence over DNS resolution. If this file is maliciously modified, it could cause the failure or compromise of security functions requiring name resolution, which may include time synchronization, centralized authentication, and remote system logging.System AdministratorECLP-1

Checks: C-36009r2_chk

Check the /etc/hosts file's group ownership. Procedure: # ls -lL /etc/hosts If the file is not group-owned by root, bin, or sys, this is a finding.

Fix: F-31260r2_fix

Change the group-owner of the /etc/hosts file to root, sys, or bin. Procedure: # chgrp root /etc/hosts

b

The /etc/hosts file must have mode 0644 or less permissive.

AC-6 - Medium - CCI-000225 - V-22325 - SV-37321r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001368

Vuln IDs

V-22325

Rule IDs

SV-37321r1_rule

The /etc/hosts file (or equivalent) configures local host name to IP address mappings that typically take precedence over DNS resolution. If this file is maliciously modified, it could cause the failure or compromise of security functions requiring name resolution, which may include time synchronization, centralized authentication, and remote system logging.System AdministratorECLP-1

Checks: C-36013r1_chk

Check the mode of the /etc/hosts file. # ls -l /etc/hosts If the file mode is not 0644, this is a finding.

Fix: F-31264r1_fix

Change the mode of the /etc/hosts file to 0644. # chmod 0644 /etc/hosts

b

The /etc/hosts file must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22326 - SV-37324r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001369

Vuln IDs

V-22326

Rule IDs

SV-37324r1_rule

The /etc/hosts file (or equivalent) configures local host name to IP address mappings that typically take precedence over DNS resolution. If this file is maliciously modified, it could cause the failure or compromise of security functions requiring name resolution, which may include time synchronization, centralized authentication, and remote system logging.System AdministratorECLP-1

Checks: C-36016r1_chk

Verify /etc/hosts has no extended ACL. # ls -l /etc/hosts If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-23600r1_fix

Remove the extended ACL from the file. # setfacl --remove-all /etc/hosts

b

The /etc/nsswitch.conf file must be owned by root.

AC-6 - Medium - CCI-000225 - V-22327 - SV-37326r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001371

Vuln IDs

V-22327

Rule IDs

SV-37326r1_rule

The nsswitch.conf file (or equivalent) configures the source of a variety of system security information including account, group, and host lookups. Malicious changes could prevent the system from functioning or compromise system security.System AdministratorECLP-1

Checks: C-36018r1_chk

Verify the /etc/nsswitch.conf file is owned by root. # ls -l /etc/nsswitch.conf If the file is not owned by root, this is a finding.

Fix: F-31267r1_fix

Change the owner of the /etc/nsswitch.conf file to root. # chown root /etc/nsswitch.conf

b

The /etc/nsswitch.conf file must be group-owned by root, bin, or sys.

AC-6 - Medium - CCI-000225 - V-22328 - SV-37330r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001372

Vuln IDs

V-22328

Rule IDs

SV-37330r1_rule

The nsswitch.conf file (or equivalent) configures the source of a variety of system security information including account, group, and host lookups. Malicious changes could prevent the system from functioning or compromise system security.System AdministratorECLP-1

Checks: C-36019r1_chk

Check the group ownership of the nsswitch.conf file. Procedure: # ls -lL /etc/nsswitch.conf If the file is not group-owned by root, bin or sys, this is a finding.

Fix: F-31268r1_fix

Change the group-owner of the /etc/nsswitch.conf file to root, bin or sys. Procedure: # chgrp root /etc/nsswitch.conf

b

The /etc/nsswitch.conf file must have mode 0644 or less permissive.

AC-6 - Medium - CCI-000225 - V-22329 - SV-37332r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001373

Vuln IDs

V-22329

Rule IDs

SV-37332r1_rule

The nsswitch.conf file (or equivalent) configures the source of a variety of system security information including account, group, and host lookups. Malicious changes could prevent the system from functioning or compromise system security.System AdministratorECLP-1

Checks: C-36022r1_chk

Check the mode of the /etc/nsswitch.conf file. # ls -l /etc/nsswitch.conf If the file mode is not 0644, this is a finding.

Fix: F-31270r1_fix

Change the mode of the /etc/nsswitch.conf file to 0644 or less permissive. # chmod 0644 /etc/nsswitch.conf

b

The /etc/nsswitch.conf file must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22330 - SV-37334r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001374

Vuln IDs

V-22330

Rule IDs

SV-37334r1_rule

The nsswitch.conf file (or equivalent) configures the source of a variety of system security information including account, group, and host lookups. Malicious changes could prevent the system from functioning or compromise system security.System AdministratorECLP-1

Checks: C-36025r1_chk

Verify /etc/nsswitch.conf has no extended ACL. # ls -l /etc/nsswitch.conf If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-23607r1_fix

Remove the extended ACL from the file. # setfacl --remove-all /etc/nsswitch.conf

a

For systems using DNS resolution, at least two name servers must be configured.

SC-22 - Low - CCI-001182 - V-22331 - SV-37335r2_rule

RMF Control

SC-22

Severity

L

CCI

CCI-001182

Version

GEN001375

Vuln IDs

V-22331

Rule IDs

SV-37335r2_rule

To provide availability for name resolution services, multiple redundant name servers are mandated. A failure in name resolution could lead to the failure of security functions requiring name resolution, which may include time synchronization, centralized authentication, and remote system logging.System AdministratorECSC-1

Checks: C-36026r1_chk

Determine if DNS is enabled on the system. # grep dns /etc/nsswitch.conf If no line is returned, or any returned line is commented out, the system does not use DNS, and this is not applicable. Determine the name servers used by the system. # grep nameserver /etc/resolv.conf If less than two lines are returned that are not commented out, this is a finding.

Fix: F-31272r1_fix

Edit /etc/resolv.conf and add additional "nameserver" lines until at least two are present.

b

The /etc/passwd file must be owned by root.

AC-6 - Medium - CCI-000225 - V-22332 - SV-37336r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001378

Vuln IDs

V-22332

Rule IDs

SV-37336r1_rule

The /etc/passwd file contains the list of local system accounts. It is vital to system security and must be protected from unauthorized modification.System AdministratorECLP-1

Checks: C-36027r1_chk

Verify the /etc/passwd file is owned by root. # ls -l /etc/passwd If the file is not owned by root, this is a finding.

Fix: F-31273r1_fix

Change the owner of the /etc/passwd file to root. # chown root /etc/passwd

b

The /etc/passwd file must be group-owned by root, bin, or sys.

AC-6 - Medium - CCI-000225 - V-22333 - SV-37337r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001379

Vuln IDs

V-22333

Rule IDs

SV-37337r1_rule

The /etc/passwd file contains the list of local system accounts. It is vital to system security and must be protected from unauthorized modification.System AdministratorECLP-1

Checks: C-36028r1_chk

Check the group ownership of the passwd file. Procedure: # ls -lL /etc/passwd If the file is not group-owned by root, bin or sys, this is a finding.

Fix: F-31274r1_fix

Change the group-owner of the /etc/passwd file to root, bin or sys. Procedure: # chgrp root /etc/passwd

b

The /etc/passwd file must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22334 - SV-37346r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001390

Vuln IDs

V-22334

Rule IDs

SV-37346r1_rule

File system ACLs can provide access to files beyond what is allowed by the mode numbers of the files. The /etc/passwd file contains the list of local system accounts. It is vital to system security and must be protected from unauthorized modification.System AdministratorECLP-1

Checks: C-36038r1_chk

Verify /etc/passwd has no extended ACL. # ls -l /etc/passwd If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-23614r1_fix

Remove the extended ACL from the file. # setfacl --remove-all /etc/passwd

b

The /etc/group file must be owned by root.

AC-6 - Medium - CCI-000225 - V-22335 - SV-37351r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001391

Vuln IDs

V-22335

Rule IDs

SV-37351r1_rule

The /etc/group file is critical to system security and must be owned by a privileged user. The group file contains a list of system groups and associated information.System AdministratorECLP-1

Checks: C-36042r1_chk

Verify the /etc/group file is owned by root. # ls -l /etc/group If the file is not owned by root, this is a finding.

Fix: F-31286r1_fix

Change the owner of the /etc/group file to root. # chown root /etc/group

b

The /etc/group file must be group-owned by root, bin, or sys.

AC-6 - Medium - CCI-000225 - V-22336 - SV-37352r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001392

Vuln IDs

V-22336

Rule IDs

SV-37352r1_rule

The /etc/group file is critical to system security and must be protected from unauthorized modification. The group file contains a list of system groups and associated information.System AdministratorECLP-1

Checks: C-36043r1_chk

Check the group ownership of the /etc/group file. Procedure: # ls -lL /etc/group If the file is not group-owned by root, bin or sys, this is a finding.

Fix: F-31287r1_fix

Change the group-owner of the /etc/group file. Procedure: # chgrp root /etc/group

b

The /etc/group file must have mode 0644 or less permissive.

AC-6 - Medium - CCI-000225 - V-22337 - SV-37354r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001393

Vuln IDs

V-22337

Rule IDs

SV-37354r1_rule

The /etc/group file is critical to system security and must be protected from unauthorized modification. The group file contains a list of system groups and associated information.System AdministratorECLP-1

Checks: C-36045r1_chk

Check the mode of the /etc/group file. # ls -l /etc/group If the file mode is more permissive than 0644, this is a finding.

Fix: F-31289r1_fix

Change the mode of the /etc/group file to 0644 or less permissive. # chmod 0644 /etc/group

b

The /etc/group file must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22338 - SV-37357r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001394

Vuln IDs

V-22338

Rule IDs

SV-37357r1_rule

The /etc/group file is critical to system security and must be protected from unauthorized modification. The group file contains a list of system groups and associated information.System AdministratorECLP-1

Checks: C-36047r1_chk

Verify /etc/group has no extended ACL. # ls -l /etc/group If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-31291r1_fix

Remove the extended ACL from the file. # setfacl --remove-all /etc/group

b

The /etc/shadow file (or equivalent) must be group-owned by root, bin, or sys.

AC-6 - Medium - CCI-000225 - V-22339 - SV-37365r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001410

Vuln IDs

V-22339

Rule IDs

SV-37365r1_rule

The /etc/shadow file contains the list of local system accounts. It is vital to system security and must be protected from unauthorized modification. The file also contains password hashes which must not be accessible to users other than root.System AdministratorECLP-1

Checks: C-36053r1_chk

Check the ownership of the /etc/shadow file. Procedure: # ls -lL /etc/shadow If the file is not group-owned by root, bin, or sys, this is a finding.

Fix: F-31297r1_fix

Change the group-owner of the /etc/shadow file. Procedure: # chgrp root /etc/shadow

b

The /etc/shadow file must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22340 - SV-37371r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001430

Vuln IDs

V-22340

Rule IDs

SV-37371r1_rule

The /etc/shadow file contains the list of local system accounts. It is vital to system security and must be protected from unauthorized modification. The file also contains password hashes which must not be accessible to users other than root.System AdministratorECLP-1

Checks: C-36058r1_chk

Verify /etc/shadow has no extended ACL. # ls -l /etc/shadow If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-31303r1_fix

Remove the extended ACL from the file. # setfacl --remove-all /etc/shadow

b

The /etc/gshadow file must be owned by root.

AC-6 - Medium - CCI-000225 - V-22341 - SV-37143r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN000000-LNX001431

Vuln IDs

V-22341

Rule IDs

SV-37143r1_rule

The /etc/gshadow file is critical to system security and must be owned by a privileged user. The /etc/gshadow file contains a list of system groups and hashes for group passwords.System AdministratorECLP-1

Checks: C-35861r1_chk

Check the /etc/gshadow file is owned by root. # ls -l /etc/gshadow If the file is not owned by root, this is a finding.

Fix: F-31110r1_fix

Change the owner of the /etc/gshadow file to root. # chown root /etc/gshadow

b

The /etc/gshadow file must be group-owned by root.

AC-6 - Medium - CCI-000225 - V-22342 - SV-37164r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN000000-LNX001432

Vuln IDs

V-22342

Rule IDs

SV-37164r1_rule

The /etc/gshadow file is critical to system security and must be protected from unauthorized modification. The /etc/gshadow file contains a list of system groups and hashes for group passwords.System AdministratorECLP-1

Checks: C-35871r1_chk

Check the /etc/gshadow file is group-owned by root. # ls -l /etc/gshadow If the file is not group-owned by root, this is a finding.

Fix: F-31125r1_fix

Change the group-owner of the /etc/gshadow file to root. # chgrp root /etc/gshadow

b

The /etc/gshadow file must have mode 0400.

AC-6 - Medium - CCI-000225 - V-22343 - SV-37170r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN000000-LNX001433

Vuln IDs

V-22343

Rule IDs

SV-37170r1_rule

The /etc/gshadow file is critical to system security and must be protected from unauthorized modification. The /etc/gshadow file contains a list of system groups and hashes for group passwords.System AdministratorECLP-1

Checks: C-35875r1_chk

Check the mode of the /etc/gshadow file. # ls -l /etc/gshadow If the file mode is more permissive than 0400, this is a finding.

Fix: F-31130r1_fix

Change the mode of the /etc/gshadow file to 0400 or less permissive. # chmod 0400 /etc/gshadow

b

The /etc/gshadow file must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22344 - SV-37176r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN000000-LNX001434

Vuln IDs

V-22344

Rule IDs

SV-37176r1_rule

The /etc/gshadow file is critical to system security and must be protected from unauthorized modification. The /etc/gshadow file contains a list of system groups and hashes for group passwords.System AdministratorECLP-1

Checks: C-35880r1_chk

Check /etc/gshadow has no extended ACL. # ls -l /etc/gshadow If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-31135r1_fix

Remove the extended ACL from the file. # setfacl --remove-all /etc/gshadow

b

The /etc/passwd file must not contain password hashes.

IA-5 - Medium - CCI-000201 - V-22347 - SV-37381r2_rule

RMF Control

IA-5

Severity

M

CCI

CCI-000201

Version

GEN001470

Vuln IDs

V-22347

Rule IDs

SV-37381r2_rule

If password hashes are readable by non-administrators, the passwords are subject to attack through lookup tables or cryptographic weaknesses in the hashes.System AdministratorECLP-1

Checks: C-36068r2_chk

Verify no password hashes are present in /etc/passwd. # cut -d : -f 2 /etc/passwd | egrep -v '^(x|\*)$' If any password hashes are returned, this is a finding.

Fix: F-31312r1_fix

Migrate /etc/passwd password hashes to /etc/shadow. # pwconv

b

The /etc/group file must not contain any group password hashes.

AC-6 - Medium - CCI-000225 - V-22348 - SV-37383r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001475

Vuln IDs

V-22348

Rule IDs

SV-37383r1_rule

Group passwords are typically shared and should not be used. Additionally, if password hashes are readable by non-administrators, the passwords are subject to attack through lookup tables or cryptographic weaknesses in the hashes.System AdministratorECLP-1

Checks: C-36070r1_chk

Check the /etc/group file for password hashes. # cut -d : -f 2 /etc/group | egrep -v '^(x|!)$' If any password hashes are returned, this is a finding.

Fix: F-31314r1_fix

Edit /etc/group and change the password field to an exclamation point (!) to lock the group password.

b

The /etc/gshadow file must not contain any group password hashes.

CM-6 - Medium - CCI-000366 - V-22349 - SV-37386r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN000000-LNX001476

Vuln IDs

V-22349

Rule IDs

SV-37386r1_rule

Group passwords are typically shared and should not be used.System AdministratorECLP-1

Checks: C-36073r1_chk

Check the /etc/gshadow file for password hashes. # cut -d : -f 2 /etc/gshadow | egrep -v '^(x|!!)$' If any password hashes are returned, this is a finding.

Fix: F-31317r1_fix

Edit /etc/gshadow and change the password field to an exclamation point (!) to lock the group password.

a

User home directories must not have extended ACLs.

AC-6 - Low - CCI-000225 - V-22350 - SV-37162r1_rule

RMF Control

AC-6

Severity

L

CCI

Version

GEN001490

Vuln IDs

V-22350

Rule IDs

SV-37162r1_rule

Excessive permissions on home directories allow unauthorized access to user files.System AdministratorECLP-1

Checks: C-37525r1_chk

Verify user home directories have no extended ACLs. # cut -d : -f 6 /etc/passwd | xargs -n1 ls -ld If the permissions include a '+', the file has an extended ACL this is a finding.

Fix: F-23641r1_fix

Remove the extended ACL from the file. # setfacl --remove-all [user home directory with extended ACL]

b

All files and directories contained in user home directories must be group-owned by a group of which the home directory's owner is a member.

AC-6 - Medium - CCI-000225 - V-22351 - SV-37180r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001550

Vuln IDs

V-22351

Rule IDs

SV-37180r1_rule

If a user's files are group-owned by a group of which the user is not a member, unintended users may be able to access them.System AdministratorECLP-1

Checks: C-35883r2_chk

Check the contents of user home directories for files group-owned by a group of which the home directory's owner is not a member. 1. List the user accounts. # cut -d : -f 1 /etc/passwd 2. For each user account, get a list of GIDs for files in the user's home directory. # find ~username -printf %G\\n | sort | uniq 3. Obtain the list of GIDs where the user is a member. # id -G username 4. Check the GID lists. If there are GIDs in the file list not present in the user list, this is a finding.

Fix: F-31138r1_fix

Change the group of a file not group-owned by a group of which the home directory's owner is a member. # chgrp <group with user as member> <file with bad group ownership> Document all changes.

b

All files and directories contained in user home directories must not have extended ACLs.

AC-6 - Medium - CCI-000225 - V-22352 - SV-37188r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001570

Vuln IDs

V-22352

Rule IDs

SV-37188r1_rule

Excessive permissions allow unauthorized access to user files.System AdministratorECLP-1

Checks: C-37530r1_chk

Check the contents of user home directories for files with extended ACLs. # cut -d : -f 6 /etc/passwd | xargs -n1 -IDIR ls -alLR DIR If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-32776r1_fix

Remove the extended ACL from the file. # setfacl --remove-all <user file with extended ACL>

b

All run control scripts must have no extended ACLs.

AC-6 - Medium - CCI-000225 - V-22353 - SV-37196r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001590

Vuln IDs

V-22353

Rule IDs

SV-37196r1_rule

If the startup files are writable by other users, they could modify the startup files to insert malicious commands into the startup files.System AdministratorECLP-1

Checks: C-37532r1_chk

Verify run control scripts have no extended ACLs. # ls -lL /etc/rc* /etc/init.d If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-32778r1_fix

Remove the extended ACL from the file. # setfacl --remove-all <run control script with extended ACL>

b

Run control scripts' library search paths must contain only absolute paths.

CM-6 - Medium - CCI-000366 - V-22354 - SV-37211r2_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN001605

Vuln IDs

V-22354

Rule IDs

SV-37211r2_rule

The library search path environment variable(s) contain a list of directories for the dynamic linker to search to find libraries. If this path includes the current working directory or other relative paths, libraries in these directories may be loaded instead of system libraries. This variable is formatted as a colon-separated list of directories. If there is an empty entry, such as a leading or trailing colon, or two consecutive colons, this is interpreted as the current working directory. Paths starting with a slash (/) are absolute paths. System Administrator

Checks: C-37534r2_chk

Verify run control scripts' library search paths. # grep -r LD_LIBRARY_PATH /etc/rc* /etc/init.d This variable is formatted as a colon-separated list of directories. If there is an empty entry, such as a leading or trailing colon, or two consecutive colons, this is a finding. If an entry begins with a character other than a slash (/) or other than "$PATH", it is a relative path, and this is a finding.

Fix: F-32780r1_fix

Edit the run control script and remove the relative path entry from the library search path variable.

b

Run control scripts' lists of preloaded libraries must contain only absolute paths.

CM-6 - Medium - CCI-000366 - V-22355 - SV-37215r2_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN001610

Vuln IDs

V-22355

Rule IDs

SV-37215r2_rule

The library preload list environment variable contains a list of libraries for the dynamic linker to load before loading the libraries required by the binary. If this list contains paths to libraries relative to the current working directory, unintended libraries may be preloaded. This variable is formatted as a space-separated list of libraries. Paths starting with a slash (/) are absolute paths.System Administrator

Checks: C-37535r2_chk

Verify run control scripts' library preload list. # grep -r LD_PRELOAD /etc/rc* /etc/init.d This variable is formatted as a colon-separated list of paths. If there is an empty entry, such as a leading or trailing colon, or two consecutive colons, this is a finding. If an entry begins with a character other than a slash (/) or other than "$PATH", it is a relative path, and this is a finding.

Fix: F-32781r1_fix

Edit the run control script and remove the relative path entry from the library preload variable.

b

All global initialization files must not have extended ACLs.

AC-6 - Medium - CCI-000225 - V-22356 - SV-37279r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001730

Vuln IDs

V-22356

Rule IDs

SV-37279r1_rule

Global initialization files are used to configure the user's shell environment upon login. Malicious modification of these files could compromise accounts upon logon.System AdministratorECLP-1

Checks: C-35970r1_chk

Check global initialization files for extended ACLs: # ls -l /etc/bashrc /etc/csh.cshrc /etc/csh.login /etc/csh.logout /etc/environment /etc/ksh.kshrc /etc/profile /etc/suid_profile /etc/profile.d/* 2>null|grep "\+ " If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-31225r1_fix

Remove the extended ACL from the file. # ls -l etc/bashrc /etc/csh.cshrc /etc/csh.login /etc/csh.logout /etc/environment /etc/ksh.kshrc /etc/profile /etc/suid_profile /etc/profile.d/* 2>null|grep "\+ "|sed "s/^.* \///g"|xargs setfacl --remove-all

b

Skeleton files must not have extended ACLs.

AC-6 - Medium - CCI-000225 - V-22357 - SV-37297r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001810

Vuln IDs

V-22357

Rule IDs

SV-37297r1_rule

If the skeleton files are not protected, unauthorized personnel could change user startup parameters and possibly jeopardize user files.System AdministratorECLP-1

Checks: C-35991r2_chk

Check skeleton files for extended ACLs: # ls -alL /etc/skel If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-31245r1_fix

Remove the extended ACL from the file. # setfacl --remove-all [skeleton file with extended ACL] or: # ls -lL /etc/skel|grep "\+ "|sed "s/^.* \//|xargs setfacl --remove-all will remove all ACLs from the files.

b

All skeleton files (typically in /etc/skel) must be group-owned by root, bin, sys, system, or other.

AC-6 - Medium - CCI-000225 - V-22358 - SV-37237r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001830

Vuln IDs

V-22358

Rule IDs

SV-37237r1_rule

If the skeleton files are not protected, unauthorized personnel could change user startup parameters and possibly jeopardize user files.System AdministratorECLP-1

Checks: C-35927r1_chk

Verify the skeleton files are group-owned by root. Procedure: # ls -alL /etc/skel If a skeleton file is not group-owned by root, bin, sys, system, or other this is a finding.

Fix: F-31184r1_fix

b

Global initialization files' library search paths must contain only absolute paths.

CM-6 - Medium - CCI-000366 - V-22359 - SV-37246r2_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN001845

Vuln IDs

V-22359

Rule IDs

SV-37246r2_rule

The library search path environment variable(s) contain a list of directories for the dynamic linker to search to find libraries. If this path includes the current working directory or other relative paths, libraries in these directories may be loaded instead of system libraries. This variable is formatted as a colon-separated list of directories. If there is an empty entry, such as a leading or trailing colon, or two consecutive colons, this is interpreted as the current working directory. Paths starting with a slash (/) are absolute paths.System Administrator

Checks: C-35936r2_chk

Check the global initialization files' library search paths. Procedure: # grep LD_LIBRARY_PATH /etc/bashrc /etc/csh.cshrc /etc/csh.login /etc/csh.logout /etc/environment /etc/ksh.kshrc /etc/profile /etc/suid_profile /etc/profile.d/* This variable is formatted as a colon-separated list of directories. If there is an empty entry, such as a leading or trailing colon, or two consecutive colons, this is a finding. If an entry begins with a character other than a slash (/) or other than "$PATH", it is a relative path, and this is a finding.

Fix: F-31193r1_fix

Edit the global initialization file and remove the relative path entry from the library search path variable.

b

Global initialization files' lists of preloaded libraries must contain only absolute paths.

CM-6 - Medium - CCI-000366 - V-22360 - SV-37248r2_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN001850

Vuln IDs

V-22360

Rule IDs

SV-37248r2_rule

The library preload list environment variable contains a list of libraries for the dynamic linker to load before loading the libraries required by the binary. If this list contains paths to libraries relative to the current working directory, unintended libraries may be preloaded. This variable is formatted as a space-separated list of libraries. Paths starting with a slash (/) are absolute paths.System Administrator

Checks: C-35938r2_chk

Check the global initialization files' library preload list. # grep -r LD_PRELOAD /etc/bashrc /etc/csh.cshrc /etc/csh.login /etc/csh.logout /etc/environment /etc/ksh.kshrc /etc/profile /etc/suid_profile /etc/profile.d/* This variable is formatted as a colon-separated list of paths. If there is an empty entry, such as a leading or trailing colon, or two consecutive colons, this is a finding. If an entry begins with a character other than a slash (/) or other than "$PATH", it is a relative path, and this is a finding.

Fix: F-31195r1_fix

Edit the global initialization file and remove the relative path entry from the library preload variable.

b

Local initialization files must be group-owned by the user's primary group or root.

AC-6 - Medium - CCI-000225 - V-22361 - SV-37252r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001870

Vuln IDs

V-22361

Rule IDs

SV-37252r1_rule

Local initialization files are used to configure the user's shell environment upon login. Malicious modification of these files could compromise accounts upon logon.System AdministratorECLP-1

Checks: C-35943r1_chk

Check user home directories for local initialization files group-owned by a group other than the user's primary group or root. Procedure: # FILES=" .login .cshrc .logout .profile .bash_profile .bashrc .bash_logout .env .dtprofile .dispatch .emacs .exrc"; # for PWLINE in `cut -d: -f4,6 /etc/passwd`; do HOMEDIR=$(echo ${PWLINE}|cut -d: -f2);GROUP=$(echo ${PWLINE} | cut -d: -f1);for INIFILE in $FILES;do stat -c %g/%G:%n ${HOMEDIR}/${INIFILE} 2>null|egrep -v "${GROUP}";done;done If any file is not group-owned by root or the user's primary GID, this is a finding.

Fix: F-31199r1_fix

Change the group-owner of the local initialization file to the user's primary group, or root. # chgrp <user's primary GID> <user's local initialization file> Procedure: # FILES=".bashrc .bash_login .bash_logout .bash_profile .cshrc .kshrc .login .logout .profile .tcshrc .env .dtprofile .dispatch .emacs .exrc"; # for PWLINE in `cut -d: -f4,6 /etc/passwd`; do HOMEDIR=$(echo ${PWLINE}|cut -d: -f2);GROUP=$(echo ${PWLINE} | cut -d: -f1);for INIFILE in $FILES;do MATCH=$(stat -c %g/%G:%n ${HOMEDIR}/${INIFILE} 2>null|egrep -c -v "${GROUP}");if [ $MATCH != 0 ] ; then chgrp ${GROUP} ${HOMEDIR}/${INIFILE};fi;done;done

b

Local initialization files must not have extended ACLs.

AC-6 - Medium - CCI-000225 - V-22362 - SV-37271r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN001890

Vuln IDs

V-22362

Rule IDs

SV-37271r1_rule

Local initialization files are used to configure the user's shell environment upon login. Malicious modification of these files could compromise accounts upon logon.System AdministratorECLP-1

Checks: C-35963r1_chk

Check user home directories for local initialization files with extended ACLs. # cut -d : -f 6 /etc/passwd | xargs -n1 -IDIR ls -alL DIR/.bashrc DIR/.bash_login DIR/.bash_logout DIR/.bash_profile DIR/.cshrc DIR/.kshrc DIR/.login DIR/.logout DIR/.profile DIR/.env DIR/.dtprofile DIR/.dispatch DIR/.emacs DIR/.exrc If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-31219r1_fix

Remove the extended ACL from the file. # setfacl --remove-all <local initialization file with extended ACL>

b

Local initialization files' library search paths must contain only absolute paths.

CM-6 - Medium - CCI-000366 - V-22363 - SV-37305r3_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN001901

Vuln IDs

V-22363

Rule IDs

SV-37305r3_rule

The library search path environment variable(s) contain a list of directories for the dynamic linker to search to find libraries. If this path includes the current working directory or other relative paths, libraries in these directories may be loaded instead of system libraries. This variable is formatted as a colon-separated list of directories. If there is an empty entry, such as a leading or trailing colon, or two consecutive colons, this is interpreted as the current working directory. Paths starting with a slash (/) are absolute paths.System Administrator

Checks: C-36000r3_chk

Verify local initialization files have library search path containing only absolute paths. Procedure: NOTE: This must be done in the BASH shell. # cut -d: -f6 /etc/passwd |xargs -n1 -IDIR find DIR -name ".*" -type f -maxdepth 1 -exec grep -H LD_LIBRARY_PATH {} \; This variable is formatted as a colon-separated list of directories. If there is an empty entry, such as a leading or trailing colon, or two consecutive colons, this is a finding. If an entry begins with a character other than a slash (/) or other than "$PATH", it is a relative path, and this is a finding.

Fix: F-31253r1_fix

Edit the local initialization file and remove the relative path entry from the library search path variable.

b

Local initialization files' lists of preloaded libraries must contain only absolute paths.

CM-6 - Medium - CCI-000366 - V-22364 - SV-37312r3_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN001902

Vuln IDs

V-22364

Rule IDs

SV-37312r3_rule

The library preload list environment variable contains a list of libraries for the dynamic linker to load before loading the libraries required by the binary. If this list contains paths to libraries relative to the current working directory, unintended libraries may be preloaded. This variable is formatted as a space-separated list of libraries. Paths starting with a slash (/) are absolute paths.System Administrator

Checks: C-36005r3_chk

Verify local initialization files have library preload list containing only absolute paths. NOTE: The following must be done in the BASH shell. Procedure: # cut -d: -f6 /etc/passwd |xargs -n1 -IDIR find DIR -name ".*" -type f -maxdepth 1 -exec grep -H LD_PRELOAD {} \; This variable is formatted as a colon-separated list of paths. If there is an empty entry, such as a leading or trailing colon, or two consecutive colons, this is a finding. If an entry begins with a character other than a slash (/) or other than "$PATH", it is a relative path, and this is a finding.

Fix: F-31257r1_fix

Edit the local initialization file and remove the relative path entry from the library preload variable.

b

All shell files must be group-owned by root, bin, sys, or system.

AC-6 - Medium - CCI-000225 - V-22365 - SV-37399r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN002210

Vuln IDs

V-22365

Rule IDs

SV-37399r1_rule

If shell files are group-owned by users other than root or a system group, they could be modified by intruders or malicious users to perform unauthorized actions.System AdministratorECLP-1

Checks: C-36082r1_chk

If /etc/shells exists, check the group ownership of each shell referenced. Procedure: # cat /etc/shells | xargs -n1 ls -l Otherwise, check any shells found on the system. Procedure: # find / -name "*sh" | xargs -n1 ls -l If a shell is not group-owned by root, bin, sys, or system, this is a finding.

Fix: F-31329r1_fix

Change the group-owner of the shell to root, bin, sys, or system. Procedure: # chgrp root <shell>

b

All shell files must not have extended ACLs.

AC-6 - Medium - CCI-000225 - V-22366 - SV-37405r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN002230

Vuln IDs

V-22366

Rule IDs

SV-37405r1_rule

Shells with world/group write permissions give the ability to maliciously modify the shell to obtain unauthorized access.System AdministratorECLP-1

Checks: C-36088r1_chk

If /etc/shells exists, check the permissions of each shell referenced. # cat /etc/shells | xargs -n1 ls -lL Otherwise, check any shells found on the system. # find / -name "*sh" | xargs -n1 ls -lL If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-31335r1_fix

Remove the extended ACL from the file. # setfacl --remove-all [shell]

b

Audio devices must not have extended ACLs.

AC-6 - Medium - CCI-000225 - V-22367 - SV-37569r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN002330

Vuln IDs

V-22367

Rule IDs

SV-37569r1_rule

File system ACLs can provide access to files beyond what is allowed by the mode numbers of the files.System AdministratorECLP-1

Checks: C-36218r1_chk

Check the permissions of audio devices. # ls -lL /dev/audio* /dev/snd/* If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-31478r1_fix

Remove the extended ACL from the file. # setfacl --remove-all [device file]

b

Removable media, remote file systems, and any file system not containing approved device files must be mounted with the "nodev" option.

CM-6 - Medium - CCI-000366 - V-22368 - SV-37623r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN002430

Vuln IDs

V-22368

Rule IDs

SV-37623r1_rule

The "nodev" (or equivalent) mount option causes the system to not handle device files as system devices. This option must be used for mounting any file system not containing approved device files. Device files can provide direct access to system hardware and can compromise security if not protected.System AdministratorECSC-1

Checks: C-36822r2_chk

Check /etc/mtab and verify the "nodev" mount option is used on any filesystems mounted from removable media or network shares. If any filesystem mounted from removable media or network shares does not have this option, this is a finding.

Fix: F-31660r1_fix

Edit /etc/fstab and add the "nodev" option to any filesystems mounted from removable media or network shares.

b

All system audit files must not have extended ACLs.

AU-9 - Medium - CCI-000163 - V-22369 - SV-37917r1_rule

RMF Control

AU-9

Severity

M

CCI

CCI-000163

Version

GEN002710

Vuln IDs

V-22369

Rule IDs

SV-37917r1_rule

If a user can write to the audit logs, then audit trails can be modified or destroyed and system intrusion may not be detected.System AdministratorECTP-1

Checks: C-37143r1_chk

Check the system audit log files for extended ACLs. Procedure: # grep "^log_file" /etc/audit/auditd.conf|sed s/^[^\/]*//|xargs ls -l If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-26222r1_fix

Remove the extended ACL from the system audit file(s).

a

System audit tool executables must be owned by root.

AU-9 - Low - CCI-001493 - V-22370 - SV-26504r1_rule

RMF Control

AU-9

Severity

L

CCI

Version

GEN002715

Vuln IDs

V-22370

Rule IDs

SV-26504r1_rule

To prevent unauthorized access or manipulation of system audit logs, the tools for manipulating those logs must be protected.System AdministratorECLP-1

Checks: C-27558r1_chk

Verify the audit tool executables are owned by root. # ls -l /sbin/auditctl /sbin/auditd /sbin/ausearch /sbin/aureport /sbin/autrace /sbin/audispd If any listed file is not owned by root, this is a finding.

Fix: F-23742r1_fix

Change the owner of the audit tool executable to root. # chown root [audit tool executable]

a

System audit tool executables must be group-owned by root, bin, sys, or system.

AU-9 - Low - CCI-001493 - V-22371 - SV-26507r1_rule

RMF Control

AU-9

Severity

L

CCI

Version

GEN002716

Vuln IDs

V-22371

Rule IDs

SV-26507r1_rule

To prevent unauthorized access or manipulation of system audit logs, the tools for manipulating those logs must be protected.System AdministratorECLP-1

Checks: C-27561r1_chk

Verify the audit tool executables are group-owned by root, bin, sys, or system. Procedure: # ls -lL /sbin/auditctl /sbin/auditd /sbin/ausearch /sbin/aureport /sbin/autrace /sbin/audispd If any listed file is not group-owned by root, bin, sys, or system, this is a finding.

Fix: F-23743r1_fix

Change the group-owner of the audit tool executable to root, bin, sys, or system. Procedure: # chgrp root <audit tool executable>

a

System audit tool executables must have mode 0750 or less permissive.

AU-9 - Low - CCI-001493 - V-22372 - SV-26510r1_rule

RMF Control

AU-9

Severity

L

CCI

Version

GEN002717

Vuln IDs

V-22372

Rule IDs

SV-26510r1_rule

To prevent unauthorized access or manipulation of system audit logs, the tools for manipulating those logs must be protected.System AdministratorECLP-1

Checks: C-27564r1_chk

Check the mode of audit tool executables. # ls -l /sbin/auditctl /sbin/auditd /sbin/ausearch /sbin/aureport /sbin/autrace /sbin/audispd If any listed file has a mode more permissive than 0750, this is a finding.

Fix: F-23745r1_fix

Change the mode of the audit tool executable to 0750, or less permissive. # chmod 0750 [audit tool executable]

a

System audit tool executables must not have extended ACLs.

AU-9 - Low - CCI-001493 - V-22373 - SV-26513r1_rule

RMF Control

AU-9

Severity

L

CCI

Version

GEN002718

Vuln IDs

V-22373

Rule IDs

SV-26513r1_rule

To prevent unauthorized access or manipulation of system audit logs, the tools for manipulating those logs must be protected.System AdministratorECLP-1

Checks: C-27567r1_chk

Check the permissions of audit tool executables. # ls -l /sbin/auditctl /sbin/auditd /sbin/ausearch /sbin/aureport /sbin/autrace /sbin/audispd If the permissions include a '+' the file has an extended ACL, this is a finding.

Fix: F-23749r1_fix

Remove the extended ACL from the file. # setfacl --remove-all [audit file]

a

The audit system must alert the SA in the event of an audit processing failure.

AU-5 - Low - CCI-000139 - V-22374 - SV-68095r2_rule

RMF Control

AU-5

Severity

L

CCI

CCI-000139

Version

GEN002719

Vuln IDs

V-22374

Rule IDs

SV-68095r2_rule

An accurate and current audit trail is essential for maintaining a record of system activity. If the system fails, the SA must be notified and must take prompt action to correct the problem. Minimally, the system must log this event, and the SA will receive this notification during the daily system log review. If feasible, active alerting (such as e-mail or paging) should be employed consistent with the site's established operations management systems and procedures.System Administrator

Checks: C-54715r1_chk

Verify the /etc/audit/auditd.conf has the disk_full_action and disk_error_action parameters set. Procedure: # grep disk_full_action /etc/audit/auditd.conf If the disk_full_action parameter is missing or set to "suspend" or "ignore" this is a finding. # grep disk_error_action /etc/audit/auditd.conf If the disk_error_action parameter is missing or set to "suspend" or "ignore" this is a finding.

Fix: F-32421r1_fix

Edit /etc/audit/auditd.conf and set the disk_full_action and/or disk_error_action parameters to a valid setting of "syslog", "exec", "single" or "halt", adding the parameters if necessary.

b

The audit system must alert the SA when the audit storage volume approaches its capacity.

AU-5 - Medium - CCI-000143 - V-22375 - SV-26518r2_rule

RMF Control

AU-5

Severity

M

CCI

CCI-000143

Version

GEN002730

Vuln IDs

V-22375

Rule IDs

SV-26518r2_rule

An accurate and current audit trail is essential for maintaining a record of system activity. If the system fails, the SA must be notified and must take prompt action to correct the problem. Minimally, the system must log this event, and the SA will receive this notification during the daily system log review. If feasible, active alerting (such as e-mail or paging) should be employed consistent with the site's established operations management systems and procedures.System Administrator

Checks: C-37192r2_chk

Check /etc/audit/auditd.conf for the space_left_action and action_mail_accnt parameters. If the space_left_action or the action_mail_accnt parameters are set to blanks, this is a finding. If the space_left_action is set to "syslog", the system logs the event, this is not a finding. If the space_left_action is set to "exec", the system executes a designated script. If this script informs the SA of the event, this is not a finding. If the space_left_action parameter is missing, this is a finding. If the space_left_action parameter is set to "ignore" or "suspend" no logging would be performed after the event, this is a finding. If the space_left_action parameter is set to "single" or "halt" this effectively stops the system causing a Denial of Service, this is a finding. If the space_left_action is set to "email" and the action_mail_acct parameter is not set to the e-mail address of the system administrator, this is a finding. The action_mail_acct parameter, if missing, defaults to "root". Note that if the email address of the system administrator is on a remote system "sendmail" must be available.

Fix: F-32424r1_fix

Edit /etc/audit/auditd.conf and set the space_left_action parameter to a valid setting other than "ignore". If the space_left_action parameter is set to "email" set the action_mail_acct parameter to an e-mail address for the system administrator.

a

The audit system must be configured to audit account creation.

AC-2 - Low - CCI-000018 - V-22376 - SV-26519r1_rule

RMF Control

AC-2

Severity

L

CCI

CCI-000018

Version

GEN002750

Vuln IDs

V-22376

Rule IDs

SV-26519r1_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises, and damages incurred during a system compromise.System AdministratorECAT-1

Checks: C-27572r1_chk

Determine if execution of the useradd and groupadd executable are audited. # auditctl -l | egrep '(useradd|groupadd)' If either useradd or groupadd are not listed with a permissions filter of at least 'x', this is a finding. Determine if /etc/passwd, /etc/shadow, /etc/group, and /etc/gshadow are audited for appending. # auditctl -l | egrep '(/etc/passwd|/etc/shadow|/etc/group|/etc/gshadow)' If any of these are not listed with a permissions filter of at least 'a', this is a finding.

Fix: F-23761r1_fix

Configure execute auditing of the useradd and groupadd executables. Add the following to audit.rules: -w /usr/sbin/useradd -p x -k useradd -w /usr/sbin/groupadd -p x -k groupadd Configure append auditing of the passwd, shadow, group, and gshadow files. Add the following to audit.rules: -w /etc/passwd -p a -k passwd -w /etc/shadow -p a -k shadow -w /etc/group -p a -k group -w /etc/gshadow -p a -k gshadow Restart the auditd service.

a

The audit system must be configured to audit account modification.

AC-2 - Low - CCI-001403 - V-22377 - SV-26520r1_rule

RMF Control

AC-2

Severity

L

CCI

CCI-001403

Version

GEN002751

Vuln IDs

V-22377

Rule IDs

SV-26520r1_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System AdministratorECAT-1

Checks: C-27573r1_chk

Determine if execution of the usermod and groupmod executable are audited. # auditctl -l | egrep '(usermod|groupmod)' If either useradd or groupadd are not listed with a permissions filter of at least 'w', this is a finding. Determine if /etc/passwd, /etc/shadow, /etc/group, and /etc/gshadow are audited for writing. # auditctl -l | egrep '(/etc/passwd|/etc/shadow|/etc/group|/etc/gshadow)' If any of these are not listed with a permissions filter of at least 'w', this is a finding.

Fix: F-23762r1_fix

Configure execute auditing of the usermod and groupmod executables. Add the following to the audit.rules file: -w /usr/sbin/usermod -p x -k usermod -w /usr/sbin/groupmod -p x -k groupmod Configure append auditing of the passwd, shadow, group, and gshadow files. Add the following to the audit.rules file: -w /etc/passwd -p w -k passwd -w /etc/shadow -p w -k shadow -w /etc/group -p w -k group -w /etc/gshadow -p w -k gshadow Restart the auditd service.

a

The audit system must be configured to audit account disabling.

AC-2 - Low - CCI-001404 - V-22378 - SV-26521r1_rule

RMF Control

AC-2

Severity

L

CCI

CCI-001404

Version

GEN002752

Vuln IDs

V-22378

Rule IDs

SV-26521r1_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System AdministratorECAT-1

Checks: C-27574r1_chk

Determine if execution of the passwd executable is audited. # auditctl -l | grep /usr/bin/passwd If passwd is not listed with a permissions filter of at least 'x', this is a finding.

Fix: F-23763r1_fix

Configure execute auditing of the passwd executable. Add the following to the audit.rules file: -w /usr/bin/passwd -p x -k passwd Restart the auditd service.

a

The audit system must be configured to audit account termination.

AC-2 - Low - CCI-001405 - V-22382 - SV-26522r1_rule

RMF Control

AC-2

Severity

L

CCI

CCI-001405

Version

GEN002753

Vuln IDs

V-22382

Rule IDs

SV-26522r1_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System AdministratorECAT-1

Checks: C-37216r1_chk

Determine if execution of the userdel and groupdel executable are audited. # auditctl -l | egrep '(userdel|groupdel)' If either userdel or groupdel are not listed with a permissions filter of at least 'x', this is a finding.

Fix: F-32432r1_fix

Configure execute auditing of the userdel and groupdel executables. Add the following to the audit.rules file: -w /usr/sbin/userdel -p x -w /usr/sbin/groupdel -p x Restart the auditd service.

b

The audit system must be configured to audit the loading and unloading of dynamic kernel modules.

AU-2 - Medium - CCI-000126 - V-22383 - SV-38652r1_rule

RMF Control

AU-2

Severity

M

CCI

Version

GEN002825

Vuln IDs

V-22383

Rule IDs

SV-38652r1_rule

Actions concerning dynamic kernel modules must be recorded as they are substantial events. Dynamic kernel modules can increase the attack surface of a system. A malicious kernel module can be used to substantially alter the functioning of a system, often with the purpose of hiding a compromise from the SA.System AdministratorECAR-1

Checks: C-37564r1_chk

Determine if the init_module syscall is audited. # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -i "init_module" If the result does not contain "-S init_module", this is a finding.

Fix: F-32807r1_fix

The "-F arch=<ARCH>" restriction is required on dual-architecture systems (such as x86_64). On dual-architecture systems, two separate rules must exist - one for each architecture supported. Use the generic architectures "b32" and "b64" for specifying these rules. On single architecture systems, the "-F arch=<ARCH>" restriction may be omitted, but if present must match either the architecture of the system or its corresponding generic architecture. The architecture of the system may be determined by running "uname -m". See the auditctl(8) manpage for additional details. Any restrictions (such as with "-F") beyond those provided in the example rules are not in strict compliance with this requirement, and are a finding unless justified and documented appropriately. The use of audit keys consistent with the provided example is encouraged to provide for uniform audit logs, however omitting the audit key or using an alternate audit key is not a finding. Procedure: Configure auditing of the init_module syscalls. Add the following to the "etc/audit/audit.rules" or "etc/audit.rules" file: -a exit,always -S init_module Restart the auditd service. # service auditd restart

b

The cron.allow file must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22384 - SV-37382r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN002990

Vuln IDs

V-22384

Rule IDs

SV-37382r1_rule

A readable and/or writeable cron.allow file by other users than root could allow potential intruders and malicious users to use the file contents to help discern information, such as who is allowed to execute cron programs, which could be harmful to overall system and network security.System AdministratorECLP-1

Checks: C-36069r1_chk

Check the permissions of the cron.allow file. # ls -l /etc/cron.allow If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-31313r1_fix

Remove the extended ACL from the file. # setfacl --remove-all /etc/cron.allow

b

Crontab files must be group-owned by root, cron, or the crontab creator's primary group.

AC-6 - Medium - CCI-000225 - V-22385 - SV-37400r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003050

Vuln IDs

V-22385

Rule IDs

SV-37400r1_rule

To protect the integrity of scheduled system jobs and prevent malicious modification to these jobs, crontab files must be secured.System AdministratorECLP-1

Checks: C-36079r1_chk

Check the group ownership of the crontab files. Procedure: # ls -lL /var/spool/cron # ls -lL /etc/cron.d /etc/crontab /etc/cron.daily /etc/cron.hourly /etc/cron.monthly /etc/cron.weekly or # ls -lL /etc/cron*|grep -v deny If the group owner is not root or the crontab owner's primary group, this is a finding.

Fix: F-31323r1_fix

Change the group owner of the crontab file to root, cron, or the crontab's primary group. Procedure: # chgrp root [crontab file]

b

Crontab files must not have extended ACLs.

AC-6 - Medium - CCI-000225 - V-22386 - SV-37467r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003090

Vuln IDs

V-22386

Rule IDs

SV-37467r1_rule

To protect the integrity of scheduled system jobs and to prevent malicious modification to these jobs, crontab files must be secured. ACLs on crontab files may provide unauthorized access to the files.System AdministratorECLP-1

Checks: C-36133r1_chk

Check the permissions of the crontab files. Procedure: # ls -lL /var/spool/cron # ls -lL /etc/cron.d /etc/crontab /etc/cron.daily /etc/cron.hourly /etc/cron.monthly /etc/cron.weekly or # ls -lL /etc/cron*|grep -v deny If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-31378r1_fix

Remove the extended ACL from the file. # setfacl --remove-all [crontab file]

b

Cron and crontab directories must not have extended ACLs.

AC-6 - Medium - CCI-000225 - V-22387 - SV-37471r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003110

Vuln IDs

V-22387

Rule IDs

SV-37471r1_rule

To protect the integrity of scheduled system jobs and to prevent malicious modification to these jobs, crontab files must be secured. ACLs on cron and crontab directories may provide unauthorized access to these directories. Unauthorized modifications to these directories or their contents may result in the addition of unauthorized cron jobs or deny service to authorized cron jobs.System AdministratorECLP-1

Checks: C-36138r1_chk

Check the permissions of the crontab directories. Procedure: # ls -ld /var/spool/cron # ls -ld /etc/cron.d /etc/crontab /etc/cron.daily /etc/cron.hourly /etc/cron.monthly /etc/cron.weekly or # ls -ld /etc/cron*|grep -v deny If the permissions include a '+' the directory has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-31383r1_fix

Remove the extended ACL from the directory. # setfacl --remove-all <crontab directory>

b

The cron log files must not have extended ACLs.

AC-6 - Medium - CCI-000225 - V-22388 - SV-37477r2_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003190

Vuln IDs

V-22388

Rule IDs

SV-37477r2_rule

Cron logs contain reports of scheduled system activities and must be protected from unauthorized access or manipulation.System Administrator

Checks: C-36144r2_chk

Check the permissions of the file. Procedure: Depending on what system is used for log processing either /etc/syslog.conf or /etc/rsyslog.conf will be the logging configuration file. Check the configured cron log file found in the cron entry in /etc/syslog.conf or /etc/rsyslog.conf(normally /var/log/cron). # grep cron /etc/syslog.conf Or: # grep cron /etc/rsyslog.conf # ls -lL /var/log/cron If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-31390r1_fix

Remove the extended ACL from the file. # setfacl --remove-all /var/log/cron

b

The cron.deny file must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22389 - SV-37486r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003210

Vuln IDs

V-22389

Rule IDs

SV-37486r1_rule

If there are excessive file permissions for the cron.deny file, sensitive information could be viewed or edited by unauthorized users.System AdministratorECLP-1

Checks: C-36145r1_chk

Check the permissions of the file. # ls -lL /etc/cron.deny If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-31394r1_fix

Remove the extended ACL from the file. # setfacl --remove-all /etc/cron.deny

b

The at.allow file must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22390 - SV-37495r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003245

Vuln IDs

V-22390

Rule IDs

SV-37495r1_rule

File system extended ACLs provide access to files beyond what is allowed by the mode numbers of the files. Unauthorized modification of the at.allow file could result in Denial of Service to authorized "at" users and the granting of the ability to run "at" jobs to unauthorized users.System AdministratorECLP-1

Checks: C-36151r1_chk

Check the permissions of the file. # ls -lL /etc/at.allow If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-31402r1_fix

Remove the extended ACL from the file. # setfacl --remove-all /etc/at.allow

b

The cron.allow file must be group-owned by root, bin, sys, or cron.

AC-6 - Medium - CCI-000225 - V-22391 - SV-37499r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003250

Vuln IDs

V-22391

Rule IDs

SV-37499r1_rule

If the group of the cron.allow is not set to root, bin, sys, or cron, the possibility exists for an unauthorized user to view or edit the list of users permitted to use cron. Unauthorized modification of this file could cause Denial of Service to authorized cron users or provide unauthorized users with the ability to run cron jobs.System AdministratorECLP-1

Checks: C-36155r1_chk

Check the group ownership of the file. Procedure: # ls -lL /etc/cron.allow If the file exists and is not group-owned by root, bin, sys or cron, this is a finding.

Fix: F-31406r1_fix

Change the group ownership of the file. Procedure: # chgrp root /etc/cron.allow

b

The at.deny file must have mode 0600 or less permissive.

AC-6 - Medium - CCI-000225 - V-22392 - SV-26555r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003252

Vuln IDs

V-22392

Rule IDs

SV-26555r1_rule

The "at" daemon control files restrict access to scheduled job manipulation and must be protected. Unauthorized modification of the at.deny file could result in Denial of Service to authorized "at" users or provide unauthorized users with the ability to run "at" jobs.System AdministratorECLP-1

Checks: C-27598r1_chk

Check the permissions of the file. # ls -lL /etc/at.deny If the file has a mode more permissive than 0600, this is a finding.

Fix: F-23799r1_fix

Change the mode of the file. # chmod 0600 /etc/at.deny

b

The at.deny file must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22393 - SV-26558r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003255

Vuln IDs

V-22393

Rule IDs

SV-26558r1_rule

The "at" daemon control files restrict access to scheduled job manipulation and must be protected. Unauthorized modification of the at.deny file could result in Denial of Service to authorized "at" users or provide unauthorized users with the ability to run "at" jobs.System AdministratorECLP-1

Checks: C-36161r1_chk

Check the permissions of the file. # ls -lL /etc/at.deny If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-31412r1_fix

Remove the extended ACL from the file. # setfacl --remove-all /etc/at.deny

b

The cron.deny file must be group-owned by root, bin, or sys.

AC-6 - Medium - CCI-000225 - V-22394 - SV-26562r2_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003270

Vuln IDs

V-22394

Rule IDs

SV-26562r2_rule

Cron daemon control files restrict the scheduling of automated tasks and must be protected. Unauthorized modification of the cron.deny file could result in Denial of Service to authorized cron users or could provide unauthorized users with the ability to run cron jobs.System Administrator

Checks: C-36164r4_chk

Check the group ownership of the file. Procedure: # ls -lL /etc/cron.deny If the file is not group-owned by root, bin, or sys, this is a finding.

Fix: F-31415r1_fix

Change the group ownership of the file. # chgrp root /etc/cron.deny

b

The "at" directory must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22395 - SV-37523r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003410

Vuln IDs

V-22395

Rule IDs

SV-37523r1_rule

If the "at" directory has an extended ACL, unauthorized users could be allowed to view or to edit files containing sensitive information within the "at" directory. Unauthorized modifications could result in Denial of Service to authorized "at" jobs.System AdministratorECLP-1

Checks: C-36184r1_chk

Check the permissions of the directory. # ls -lLd /var/spool/at If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-31438r1_fix

Remove the extended ACL from the directory. # setfacl --remove-all /var/spool/at

b

The "at" directory must be group-owned by root, bin, sys, or cron.

AC-6 - Medium - CCI-000225 - V-22396 - SV-37529r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003430

Vuln IDs

V-22396

Rule IDs

SV-37529r1_rule

If the group of the "at" directory is not root, bin, sys, or cron, unauthorized users could be allowed to view or edit files containing sensitive information within the directory.System AdministratorECLP-1

Checks: C-36188r1_chk

Check the group ownership of the file. Procedure: # ls -lL /var/spool/at If the file is not group-owned by root, bin, sys, daemon or cron, this is a finding.

Fix: F-31443r1_fix

Change the group ownership of the file to root, bin, sys, daemon or cron. Procedure: # chgrp <root or other system group> <"at" directory>

b

The at.allow file must be group-owned by root, bin, sys, or cron.

AC-6 - Medium - CCI-000225 - V-22397 - SV-26569r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003470

Vuln IDs

V-22397

Rule IDs

SV-26569r1_rule

If the group owner of the at.allow file is not set to root, bin, sys, or cron, unauthorized users could be allowed to view or edit the list of users permitted to run "at" jobs. Unauthorized modification could result in Denial of Service to authorized "at" users or provide unauthorized users with the ability to run "at" jobs.System AdministratorECLP-1

Checks: C-36193r1_chk

Check the group ownership of the file. Procedure: # ls -lL /etc/at.allow If the file is not group-owned by root, bin, sys, or cron, this is a finding.

Fix: F-31450r1_fix

Change the group ownership of the file. Procedure: # chgrp root /etc/at.allow

b

The at.deny file must be group-owned by root, bin, sys, or cron.

AC-6 - Medium - CCI-000225 - V-22398 - SV-26572r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003490

Vuln IDs

V-22398

Rule IDs

SV-26572r1_rule

If the group owner of the at.deny file is not set to root, bin, sys, or cron, unauthorized users could be allowed to view or edit sensitive information contained within the file. Unauthorized modification could result in Denial of Service to authorized "at" users or provide unauthorized users with the ability to run "at" jobs.System AdministratorECLP-1

Checks: C-36197r1_chk

Check the group ownership of the file. Procedure: # ls -lL /etc/at.deny If the file is not group-owned by root, bin, sys, or cron, this is a finding.

Fix: F-31455r1_fix

Change the group ownership of the at.deny file to root, sys, bin, or cron. Procedure: # chgrp root /etc/at.deny

b

Kernel core dumps must be disabled unless needed.

CM-6 - Medium - CCI-000366 - V-22404 - SV-26604r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN003510

Vuln IDs

V-22404

Rule IDs

SV-26604r1_rule

Kernel core dumps may contain the full contents of system memory at the time of the crash. Kernel core dumps may consume a considerable amount of disk space and may result in Denial of Service by exhausting the available space on the target file system. The kernel core dump process may increase the amount of time a system is unavailable due to a crash. Kernel core dumps can be useful for kernel debugging.System AdministratorECSC-1

Checks: C-27645r1_chk

Verify the kdump service is not running. Procedure: # service kdump status If "Kdump is operational" is returned, this is a finding.

Fix: F-23849r1_fix

Disable kdump. # service kdump stop # chkconfig kdump off

a

The kernel core dump data directory must be group-owned by root, bin, sys, or system.

AC-6 - Low - CCI-000225 - V-22405 - SV-26608r1_rule

RMF Control

AC-6

Severity

L

CCI

Version

GEN003521

Vuln IDs

V-22405

Rule IDs

SV-26608r1_rule

Kernel core dumps may contain the full contents of system memory at the time of the crash. As the system memory may contain sensitive information, it must be protected accordingly. If the kernel core dump data directory is not group-owned by a system group, the core dumps contained in the directory may be subject to unauthorized access.System AdministratorECLP-1

Checks: C-27647r1_chk

Determine the kernel core dump data directory and check its ownership. Procedure: Examine /etc/kdump.conf. The "path" parameter, which defaults to /var/crash, determines the path relative to the crash dump device. The crash device is specified with a filesystem type and device, such as "ext3 /dev/sda2". Using this information, determine where this path is currently mounted on the system. # ls -ld <kernel dump data directory> If the directory is not group-owned by root, bin, sys, or system, this is a finding.

Fix: F-31609r1_fix

Change the group-owner of the kernel core dump data directory. # chgrp root <kernel core dump data directory>

a

The kernel core dump data directory must have mode 0700 or less permissive.

AC-6 - Low - CCI-000225 - V-22406 - SV-26612r2_rule

RMF Control

AC-6

Severity

L

CCI

Version

GEN003522

Vuln IDs

V-22406

Rule IDs

SV-26612r2_rule

Kernel core dumps may contain the full contents of system memory at the time of the crash. As the system memory may contain sensitive information, it must be protected accordingly. If the mode of the kernel core dump data directory is more permissive than 0700, unauthorized users may be able to view or to modify kernel core dump data files.System Administrator

Checks: C-27651r2_chk

Verify the location of the kernel core dump data directory: # grep “path” /etc/kdump.conf Note: If this setting is not configured or commented out, the default kernel dump data directory is /var/crash. Check the permissions of the dump data directory: # ls -ld <path to kernel core dump data directory> If the directory has a mode more permissive than 0700, this is a finding.

Fix: F-31610r2_fix

Set the permissions on the kernel core dump data directory to 0700. # chmod 0700 <kernel core dump data directory>

a

The kernel core dump data directory must not have an extended ACL.

AC-6 - Low - CCI-000225 - V-22407 - SV-26616r2_rule

RMF Control

AC-6

Severity

L

CCI

Version

GEN003523

Vuln IDs

V-22407

Rule IDs

SV-26616r2_rule

Kernel core dumps may contain the full contents of system memory at the time of the crash. As the system memory may contain sensitive information, it must be protected accordingly. If there is an extended ACL for the kernel core dump data directory, unauthorized users may be able to view or to modify kernel core dump data files.System Administrator

Checks: C-36352r2_chk

Determine the kernel core dump data directory and check its permissions. Procedure: Verify the location of the kernel core dump data directory: # grep “path” /etc/kdump.conf Note: If this setting is not configured or commented out, the default kernel dump data directory is /var/crash. Check the permissions of the dump data directory: # ls -ld <path to kernel core dump data directory> If the permissions include a '+', the directory has an extended ACL. If the directory has an extended ACL and it has not been documented with the ISSO, this is a finding.

Fix: F-23859r2_fix

Remove the extended ACL from the directory. # setfacl --remove-all <path to kernel core dump data directory>

b

Network interfaces must not be configured to allow user control.

AC-6 - Medium - CCI-000225 - V-22408 - SV-26620r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003581

Vuln IDs

V-22408

Rule IDs

SV-26620r1_rule

Configuration of network interfaces should be limited to privileged users. Manipulation of network interfaces may result in a Denial of Service or bypass of network security mechanisms.System AdministratorECLP-1

Checks: C-27658r1_chk

Check the system for user-controlled network interfaces. # grep -l '^USERCTL=yes' /etc/sysconfig/network-scripts/ifcfg* If any results are returned, this is a finding.

Fix: F-23863r1_fix

Edit the configuration for the user-controlled interface and remove the "USERCTL=yes" configuration line or set to "USERCTL=no".

a

The system must not process Internet Control Message Protocol (ICMP) timestamp requests.

AC-4 - Low - CCI-001551 - V-22409 - SV-37601r1_rule

RMF Control

AC-4

Severity

L

CCI

Version

GEN003602

Vuln IDs

V-22409

Rule IDs

SV-37601r1_rule

The processing of (ICMP) timestamp requests increases the attack surface of the system.System AdministratorECSC-1

Checks: C-36721r2_chk

Verify the system does not respond to ICMP TIMESTAMP_REQUESTs Procedure: # grep "timestamp" /etc/sysconfig/iptables This should return entries for "timestamp-reply" and "timestamp_request". Both should end with "-j DROP'. If either does not exist or does not "DROP" the message, this is a finding.

Fix: F-31637r1_fix

Configure the system to not respond to ICMP TIMESTAMP_REQUESTs. This is done by rejecting ICMP type 13 and 14 messages at the firewall. Procedure: Edit /etc/sysconfig/iptables to add: -A RH-Firewall-1-INPUT -p ICMP --icmp-type timestamp-request -j DROP -A RH-Firewall-1-INPUT -p ICMP --icmp-type timestamp-reply -j DROP Restart the firewall: # service iptables restart

b

The system must not respond to Internet Control Message Protocol v4 (ICMPv4) echoes sent to a broadcast address.

AC-4 - Medium - CCI-001551 - V-22410 - SV-37608r1_rule

RMF Control

AC-4

Severity

M

CCI

Version

GEN003603

Vuln IDs

V-22410

Rule IDs

SV-37608r1_rule

Responding to broadcast (ICMP) echoes facilitates network mapping and provides a vector for amplification attacks.System AdministratorECSC-1

Checks: C-36776r1_chk

Verify the system does not respond to ICMP ECHO_REQUESTs set to broadcast addresses. Procedure: # cat /proc/sys/net/ipv4/icmp_echo_ignore_broadcasts If the result is not 1, this is a finding.

Fix: F-31641r1_fix

Configure the system to not respond to ICMP ECHO_REQUESTs sent to broadcast addresses. Edit /etc/sysctl.conf and add a setting for "net.ipv4.icmp_echo_ignore_broadcasts=1" and reload the sysctls. Procedure: # echo "net.ipv4.icmp_echo_ignore_broadcasts=1" >> /etc/sysctl.conf # sysctl -p

b

The system must not respond to Internet Control Message Protocol (ICMP) timestamp requests sent to a broadcast address.

AC-4 - Medium - CCI-001551 - V-22411 - SV-29288r1_rule

RMF Control

AC-4

Severity

M

CCI

Version

GEN003604

Vuln IDs

V-22411

Rule IDs

SV-29288r1_rule

The processing of (ICMP) timestamp requests increases the attack surface of the system. Responding to broadcast ICMP timestamp requests facilitates network mapping and provides a vector for amplification attacks.GEN000000-FWThe system's firewall default-deny policy mitigates the risk from this vulnerability.System AdministratorECSC-1

Checks: C-36792r1_chk

Verify the system does not respond to ICMP TIMESTAMP_REQUESTs set to broadcast addresses. Procedure: # cat /proc/sys/net/ipv4/icmp_echo_ignore_broadcasts If the result is not 1, this is a finding. Note: The same parameter controls both ICMP ECHO_REQUESTs and TIMESTAMP_REQUESTs.

Fix: F-31645r1_fix

Configure the system to not respond to ICMP TIMESTAMP_REQUESTs sent to broadcast addresses. Edit /etc/sysctl.conf and add a setting for "net.ipv4.icmp_echo_ignore_broadcasts=1" and reload the sysctls. Procedure: # echo "net.ipv4.icmp_echo_ignore_broadcasts=1" >> /etc/sysctl.conf # sysctl -p

b

The system must not accept source-routed IPv4 packets.

AC-4 - Medium - CCI-001551 - V-22414 - SV-37622r1_rule

RMF Control

AC-4

Severity

M

CCI

Version

GEN003607

Vuln IDs

V-22414

Rule IDs

SV-37622r1_rule

Source-routed packets allow the source of the packet to suggest routers forward the packet along a different path than configured on the router, which can be used to bypass network security measures. This requirement applies only to the handling of source-routed traffic destined to the system itself, not to traffic forwarded by the system to another system, such as when IPv4 forwarding is enabled and the system is functioning as a router.System AdministratorECSC-1

Checks: C-36821r1_chk

Verify the system does not accept source-routed IPv4 packets. Procedure: # grep [01] /proc/sys/net/ipv4/conf/*/accept_source_route|egrep "default|all" If all of the resulting lines do not end with "0", this is a finding.

Fix: F-31659r1_fix

Configure the system to not accept source-routed IPv4 packets. Edit /etc/sysctl.conf and add a setting for "net.ipv4.conf.all.accept_source_route=0" and "net.ipv4.conf.default.accept_source_route=0". Reload the sysctls. Procedure: # sysctl -p

b

Proxy Address Resolution Protocol (Proxy ARP) must not be enabled on the system.

AC-4 - Medium - CCI-001551 - V-22415 - SV-37624r1_rule

RMF Control

AC-4

Severity

M

CCI

Version

GEN003608

Vuln IDs

V-22415

Rule IDs

SV-37624r1_rule

Proxy ARP allows a system to respond to ARP requests on one interface on behalf of hosts connected to another interface. If this function is enabled when not required, addressing information may be leaked between the attached network segments.System AdministratorECSC-1

Checks: C-36823r1_chk

Verify the system does not use proxy ARP. # grep [01] /proc/sys/net/ipv4/conf/*/proxy_arp|egrep "default|all" If all of the resulting lines do not end with "0", this is a finding.

Fix: F-31661r1_fix

Configure the system to not use proxy ARP. Edit /etc/sysctl.conf and add a setting for "net.ipv4.conf.all.proxy_arp=0" and "net.ipv4.conf.default.proxy_arp=0". # sysctl -p

b

The system must ignore IPv4 Internet Control Message Protocol (ICMP) redirect messages.

CM-6 - Medium - CCI-001503 - V-22416 - SV-37626r1_rule

RMF Control

CM-6

Severity

M

CCI

CCI-001503

Version

GEN003609

Vuln IDs

V-22416

Rule IDs

SV-37626r1_rule

ICMP redirect messages are used by routers to inform hosts that a more direct route exists for a particular destination. These messages modify the host's route table and are unauthenticated. An illicit ICMP redirect message could result in a man-in-the-middle attack.System AdministratorECSC-1

Checks: C-36825r1_chk

Verify the system does not accept IPv4 ICMP redirect messages. # grep [01] /proc/sys/net/ipv4/conf/*/accept_redirects|egrep "default|all" If all of the resulting lines do not end with "0", this is a finding.

Fix: F-31663r1_fix

Configure the system to not accept IPv4 ICMP redirect messages. Edit /etc/sysctl.conf and add a setting for "net.ipv4.conf.all.accept_redirects=0" and "net.ipv4.conf.default.accept_redirects=0". # sysctl -p

b

The system must not send IPv4 Internet Control Message Protocol (ICMP) redirects.

AC-4 - Medium - CCI-001551 - V-22417 - SV-37629r1_rule

RMF Control

AC-4

Severity

M

CCI

Version

GEN003610

Vuln IDs

V-22417

Rule IDs

SV-37629r1_rule

ICMP redirect messages are used by routers to inform hosts that a more direct route exists for a particular destination. These messages contain information from the system's route table possibly revealing portions of the network topology.System AdministratorECSC-1

Checks: C-36828r1_chk

Verify the system does not send IPv4 ICMP redirect messages. # grep [01] /proc/sys/net/ipv4/conf/*/send_redirects|egrep "default|all" If all of the resulting lines do not end with "0", this is a finding.

Fix: F-31666r1_fix

Configure the system to not send IPv4 ICMP redirect messages. Edit /etc/sysctl.conf and add a setting for "net.ipv4.conf.all.send_redirects=0" and "net.ipv4.conf.default.send_redirects=0". # sysctl -p

a

The system must log martian packets.

AU-2 - Low - CCI-000126 - V-22418 - SV-37630r1_rule

RMF Control

AU-2

Severity

L

CCI

Version

GEN003611

Vuln IDs

V-22418

Rule IDs

SV-37630r1_rule

Martian packets are packets containing addresses known by the system to be invalid. Logging these messages allows the SA to identify misconfigurations or attacks in progress.System AdministratorECAT-1

Checks: C-36830r1_chk

Verify the system logs martian packets. # grep [01] /proc/sys/net/ipv4/conf/*/log_martians|egrep "default|all" If all of the resulting lines do not end with "1", this is a finding.

Fix: F-31667r1_fix

Configure the system to log martian packets. Edit /etc/sysctl.conf and add a setting for "net.ipv4.conf.all.log_martians=1" and "net.ipv4.conf.default.log_martians=1". Reload the sysctls. Procedure: # sysctl -p

b

The system must be configured to use TCP syncookies when experiencing a TCP SYN flood.

SC-5 - Medium - CCI-001092 - V-22419 - SV-37633r1_rule

RMF Control

SC-5

Severity

M

CCI

CCI-001092

Version

GEN003612

Vuln IDs

V-22419

Rule IDs

SV-37633r1_rule

A TCP SYN flood attack can cause Denial of Service by filling a system's TCP connection table with connections in the SYN_RCVD state. Syncookies are a mechanism used to only track a connection when a subsequent ACK is received, verifying the initiator is attempting a valid connection and is not a flood source. This technique does not operate in a fully standards-compliant manner, but is only activated when a flood condition is detected, and allows defense of the system while continuing to service valid requests.System AdministratorECSC-1

Checks: C-36832r1_chk

Verify the system configured to use TCP syncookies when experiencing a TCP SYN flood. # cat /proc/sys/net/ipv4/tcp_syncookies If the result is not "1", this is a finding.

Fix: F-31670r1_fix

Configure the system to use TCP syncookies when experiencing a TCP SYN flood. Edit /etc/sysctl.conf and add a setting for "net.ipv4.tcp_syncookies=1". # sysctl -p

b

The system must not be configured for network bridging.

AC-4 - Medium - CCI-001551 - V-22421 - SV-37639r1_rule

RMF Control

AC-4

Severity

M

CCI

Version

GEN003619

Vuln IDs

V-22421

Rule IDs

SV-37639r1_rule

Some systems have the ability to bridge or switch frames (link-layer forwarding) between multiple interfaces. This can be useful in a variety of situations but, if enabled when not needed, has the potential to bypass network partitioning and security.System AdministratorECSC-1

Checks: C-36836r1_chk

Verify the system is not configured for bridging. # ls /proc/sys/net/bridge If the directory exists, this is a finding. # lsmod | grep '^bridge ' If any results are returned, this is a finding. Fix Text: Configure the system to not use bridging.

Fix: F-31674r1_fix

Configure the system to not use bridging. # rmmod bridge Edit /etc/modprobe.conf and add a line such as "install bridge /bin/false" to prevent the loading of the bridge module.

a

All local file systems must employ journaling or another mechanism ensuring file system consistency.

CP-10 - Low - CCI-000553 - V-22422 - SV-37401r1_rule

RMF Control

CP-10

Severity

L

CCI

CCI-000553

Version

GEN003650

Vuln IDs

V-22422

Rule IDs

SV-37401r1_rule

File system journaling, or logging, can allow reconstruction of file system data after a system crash preserving the integrity of data that may have otherwise been lost. Journaling file systems typically do not require consistency checks upon booting after a crash, which can improve system availability. Some file systems employ other mechanisms to ensure consistency also satisfying this requirement.System AdministratorECSC-1

Checks: C-36084r1_chk

Verify local filesystems use journaling. # mount | grep '^/dev/' | egrep -v 'type (ext3|ext4|jfs|reiserfs|xfs|iso9660|udf)' If a mount is listed, this is a finding.

Fix: F-31331r1_fix

Convert local file systems to use journaling or another mechanism ensuring file system consistency.

b

The inetd.conf file, xinetd.conf file, and the xinetd.d directory must be group-owned by root, bin, sys, or system.

AC-6 - Medium - CCI-000225 - V-22423 - SV-37407r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003730

Vuln IDs

V-22423

Rule IDs

SV-37407r1_rule

Failure to give ownership of sensitive files or utilities to system groups may provide unauthorized users with the potential to access sensitive information or change the system configuration possibly weakening the system's security posture.System AdministratorECLP-1

Checks: C-36090r1_chk

Check the group ownership of the xinetd configuration files and directories. Procedure: # ls -alL /etc/xinetd.conf /etc/xinetd.d If a file or directory is not group-owned by root, bin, sys, or system, this is a finding.

Fix: F-31337r1_fix

Change the group-owner of the xinetd configuration files and directories. Procedure: # chgrp -R root /etc/xinetd.conf /etc/xinetd.d

b

The inetd.conf and xinetd.conf files must not have extended ACLs.

AC-6 - Medium - CCI-000225 - V-22424 - SV-37409r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003745

Vuln IDs

V-22424

Rule IDs

SV-37409r1_rule

The Internet service daemon configuration files must be protected as malicious modification could cause Denial of Service or increase the attack surface of the system.System AdministratorECLP-1

Checks: C-36092r1_chk

Check the permissions of the xinetd configuration files. Procedure: # ls -alL /etc/xinetd.conf If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-31339r1_fix

Remove the extended ACL from the file. # setfacl --remove-all /etc/xinetd.conf

b

The xinetd.d directory must have mode 0755 or less permissive.

AC-6 - Medium - CCI-000225 - V-22425 - SV-37410r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003750

Vuln IDs

V-22425

Rule IDs

SV-37410r1_rule

The Internet service daemon configuration files must be protected as malicious modification could cause Denial of Service or increase the attack surface of the system.System AdministratorECLP-1

Checks: C-36093r1_chk

Check the permissions of the xinetd configuration directories. # ls -dlL /etc/xinetd.d If the mode of the directory is more permissive than 0755, this is a finding.

Fix: F-31340r1_fix

Change the mode of the directory. # chmod 0755 /etc/xinetd.d

b

The xinetd.d directory must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22426 - SV-37411r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003755

Vuln IDs

V-22426

Rule IDs

SV-37411r1_rule

The Internet service daemon configuration files must be protected as malicious modification could cause Denial of Service or increase the attack surface of the system.System AdministratorECLP-1

Checks: C-36094r1_chk

Check the permissions of the xinetd configuration files and directories. # ls -alL /etc/xinetd.conf /etc/xinetd.d If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-31341r1_fix

Remove the extended ACL from the file. # setfacl --remove-all /etc/xinetd.d

b

The services file must be group-owned by root, bin, sys, or system.

AC-6 - Medium - CCI-000225 - V-22427 - SV-37425r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003770

Vuln IDs

V-22427

Rule IDs

SV-37425r1_rule

Failure to give ownership of system configuration files to root or a system group provides the designated owner and unauthorized users with the potential to change the system configuration possibly weakening the system's security posture.System AdministratorECLP-1

Checks: C-36106r1_chk

Check the group ownership of the services file. Procedure: # ls -lL /etc/services If the file is not group-owned by root, bin, sys, or system, this is a finding

Fix: F-31352r1_fix

Change the group-owner of the services file. Procedure: # chgrp root /etc/services

b

The services file must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22428 - SV-37438r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003790

Vuln IDs

V-22428

Rule IDs

SV-37438r1_rule

The services file is critical to the proper operation of network services and must be protected from unauthorized modification. If the services file has an extended ACL, it may be possible for unauthorized users to modify the file. Unauthorized modification could result in the failure of network services.System AdministratorECLP-1

Checks: C-36109r1_chk

Check the permissions of the /etc/services file. # ls -lL /etc/services If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-31356r1_fix

Remove the extended ACL from the file. # setfacl --remove-all /etc/services

b

The portmap or rpcbind service must not be running unless needed.

AC-17 - Medium - CCI-001436 - V-22429 - SV-26662r1_rule

RMF Control

AC-17

Severity

M

CCI

Version

GEN003810

Vuln IDs

V-22429

Rule IDs

SV-26662r1_rule

The portmap and rpcbind services increase the attack surface of the system and should only be used when needed. The portmap or rpcbind services are used by a variety of services using Remote Procedure Calls (RPCs).System AdministratorECSC-1

Checks: C-27694r1_chk

Check the status of the portmap service. # service portmap status If the service is running, this is a finding.

Fix: F-23904r1_fix

Shutdown and disable the portmap service. # service portmap stop; chkconfig portmap off

b

The portmap or rpcbind service must not be installed unless needed.

CM-2 - Medium - CCI-000305 - V-22430 - SV-26666r1_rule

RMF Control

CM-2

Severity

M

CCI

Version

GEN003815

Vuln IDs

V-22430

Rule IDs

SV-26666r1_rule

The portmap and rpcbind services increase the attack surface of the system and should only be used when needed. The portmap or rpcbind services are used by a variety of services using Remote Procedure Calls (RPCs).System AdministratorECSC-1

Checks: C-27698r1_chk

Check if the portmap package is installed. # rpm -qa | grep portmap If a package is found, this is a finding.

Fix: F-23908r1_fix

Remove the portmap package. # rpm -e portmap or # yum remove portmap

b

The rshd service must not be installed.

CM-2 - Medium - CCI-000305 - V-22431 - SV-26667r1_rule

RMF Control

CM-2

Severity

M

CCI

Version

GEN003825

Vuln IDs

V-22431

Rule IDs

SV-26667r1_rule

The rshd process provides a typically unencrypted, host-authenticated remote access service. SSH should be used in place of this service.System AdministratorDCPP-1

Checks: C-27699r1_chk

Check if the rsh-server package is installed. Procedure: # rpm -qa | grep rsh-server If a package is found, this is a finding.

Fix: F-23909r1_fix

Remove the rsh-server package. Procedure: # rpm -e rsh-server

b

The rlogind service must not be running.

AC-17 - Medium - CCI-000068 - V-22432 - SV-26671r1_rule

RMF Control

AC-17

Severity

M

CCI

Version

GEN003830

Vuln IDs

V-22432

Rule IDs

SV-26671r1_rule

The rlogind process provides a typically unencrypted, host-authenticated remote access service. SSH should be used in place of this service.System AdministratorDCPP-1

Checks: C-27701r1_chk

Check the rlogind configuration. # cat /etc/xinetd.d/rlogin If the file exists and does not contain "disable = yes" this is a finding.

Fix: F-23912r1_fix

Remove or disable the rlogin configuration and restart xinetd. # rm /etc/xinetd.d/rlogin ; service xinetd restart

b

The rlogind service must not be installed.

CM-2 - Medium - CCI-000305 - V-22433 - SV-26669r1_rule

RMF Control

CM-2

Severity

M

CCI

Version

GEN003835

Vuln IDs

V-22433

Rule IDs

SV-26669r1_rule

The rlogind process provides a typically unencrypted, host-authenticated remote access service. SSH should be used in place of this service.System AdministratorDCPP-1

Checks: C-27699r1_chk

Check if the rsh-server package is installed. Procedure: # rpm -qa | grep rsh-server If a package is found, this is a finding.

Fix: F-23909r1_fix

Remove the rsh-server package. Procedure: # rpm -e rsh-server

b

The rexecd service must not be installed.

CM-2 - Medium - CCI-000305 - V-22434 - SV-26673r1_rule

RMF Control

CM-2

Severity

M

CCI

Version

GEN003845

Vuln IDs

V-22434

Rule IDs

SV-26673r1_rule

The rexecd process provides a typically unencrypted, host-authenticated remote access service. SSH should be used in place of this service.System AdministratorECSC-1

Checks: C-27699r1_chk

Check if the rsh-server package is installed. Procedure: # rpm -qa | grep rsh-server If a package is found, this is a finding.

Fix: F-23909r1_fix

Remove the rsh-server package. Procedure: # rpm -e rsh-server

b

The hosts.lpd (or equivalent) file must be group-owned by lp.

AC-6 - Medium - CCI-000225 - V-22435 - SV-37449r2_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003930

Vuln IDs

V-22435

Rule IDs

SV-37449r2_rule

Failure to give group-ownership of the hosts.lpd file to root, bin, sys, or system provides the members of the owning group and possible unauthorized users, with the potential to modify the hosts.lpd file. Unauthorized modifications could disrupt access to local printers from authorized remote hosts or permit unauthorized remote access to local printers.System Administrator

Checks: C-36121r1_chk

Check the group ownership of the /etc/cups/printers.conf file. Procedure: # ls -lL /etc/cups/printers.conf If the file is not group-owned by lp, this is a finding.

Fix: F-31367r1_fix

Change the group-owner of the printers.conf file. Procedure: # chgrp lp /etc/cups/printers.conf

b

The hosts.lpd (or equivalent) file must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22436 - SV-37462r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003950

Vuln IDs

V-22436

Rule IDs

SV-37462r1_rule

Excessive permissions on the hosts.lpd (or equivalent) file may permit unauthorized modification. Unauthorized modifications could disrupt access to local printers from authorized remote hosts or permit unauthorized remote access to local printers.System AdministratorECLP-1

Checks: C-36128r2_chk

Check the permissions of the /etc/cups/printers.conf file. # ls -lL /etc/cups/printers.conf If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-31372r1_fix

Remove the extended ACL from the file. # setfacl --remove-all /etc/cups/printers.conf

b

The traceroute file must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22437 - SV-37468r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN004010

Vuln IDs

V-22437

Rule IDs

SV-37468r1_rule

If an extended ACL exists on the traceroute executable file, it may provide unauthorized users with access to the file. Malicious code could be inserted by an attacker and triggered whenever the traceroute command is executed by authorized users. Additionally, if an unauthorized user is granted executable permissions to the traceroute command, it could be used to gain information about the network topology behind the firewall. This information may allow an attacker to determine trusted routers and other network information potentially leading to system and network compromise.System AdministratorECLP-1

Checks: C-36134r1_chk

Check the permissions of the /bin/traceroute file. # ls -lL /bin/traceroute If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-31379r1_fix

Remove the extended ACL from the file. # setfacl --remove-all /bin/traceroute

b

The aliases file must be group-owned by root, sys, bin, or system.

AC-6 - Medium - CCI-000225 - V-22438 - SV-37473r2_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN004370

Vuln IDs

V-22438

Rule IDs

SV-37473r2_rule

If the alias file is not group-owned by root or a system group, an unauthorized user may modify the file adding aliases to run malicious code or redirect e-mail.System Administrator

Checks: C-36139r2_chk

If the "sendmail" and "postfix" packages are not installed, this is not applicable. Check the group ownership of the alias files. Procedure: for sendmail: # ls -lL /etc/aliases If the files are not group-owned by root, this is a finding. # ls -lL /etc/aliases.db If the file is not group-owned by the same system group as sendmail, which is smmsp by default, this is a finding. for postfix: Verify the location of the alias file. # postconf alias maps This will return the location of the "aliases" file, by default "/etc/postfix/aliases" # ls -lL <postfix aliases file> If the files are not group-owned by root, this is a finding. # ls -lL <postfix aliases.db file> If the file is not group-owned by root, this is a finding.

Fix: F-31385r1_fix

Change the group-owner of the /etc/aliases file. Procedure: for sendmail: # chgrp root /etc/aliases # chgrp smmsp /etc/aliases.db The aliases.db file must be owned by the same system group as sendmail, which is smmsp by default. for postfix # chgrp root /etc/postfix/aliases # chgrp root /etc/postfix/aliases.db

b

The alias file must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22439 - SV-37488r2_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN004390

Vuln IDs

V-22439

Rule IDs

SV-37488r2_rule

Excessive permissions on the aliases file may permit unauthorized modification. If the alias file is modified by an unauthorized user, they may modify the file to run malicious code or redirect e-mail.System Administrator

Checks: C-36146r2_chk

If the "sendmail" and "postfix" packages are not installed, this is not applicable. Check the permissions of the alias file. Procedure: for sendmail: # ls -lL /etc/aliases /etc/aliases.db If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding. for postfix: Verify the location of the alias file. # postconf alias maps This will return the location of the "aliases" file, by default "/etc/postfix/aliases" # ls -lL <postfix aliases file> <postfix aliases.db file> If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-31396r1_fix

Remove the extended permissions from the alias files. Procedure: for sendmail: # setfacl --remove-all /etc/aliases /etc/aliases.db for postfix (assuming the default postfix directory): # setfacl --remove-all /etc/postfix/aliases /etc/postfix/aliases.db

b

Files executed through a mail aliases file must be group-owned by root, bin, sys, or system, and must reside within a directory group-owned by root, bin, sys, or system.

AC-6 - Medium - CCI-000225 - V-22440 - SV-37493r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN004410

Vuln IDs

V-22440

Rule IDs

SV-37493r1_rule

If a file executed through a mail aliases file is not group-owned by root or a system group, it may be subject to unauthorized modification. Unauthorized modification of files executed through aliases may allow unauthorized users to attain root privileges.System AdministratorECLP-1

Checks: C-36150r1_chk

Examine the contents of the /etc/aliases file. Procedure: # more /etc/aliases Examine the aliases file for any utilized directories or paths. # ls -lL <file referenced from aliases> Check the permissions for any paths referenced. If the group owner of any file is not root, bin, sys, or system, this is a finding.

Fix: F-31401r1_fix

Change the group ownership of the file referenced from /etc/aliases. Procedure: # chgrp root <file referenced from aliases>

b

Files executed through a mail aliases file must not have extended ACLs.

AC-6 - Medium - CCI-000225 - V-22441 - SV-37496r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN004430

Vuln IDs

V-22441

Rule IDs

SV-37496r1_rule

Excessive permissions on files executed through a mail aliases file could result in modification by an unauthorized user, execution of malicious code, and/or system compromise.System AdministratorECLP-1

Checks: C-36153r1_chk

Examine the contents of the /etc/aliases file. Procedure: # more /etc/aliases Examine the aliases file for any utilized directories or paths. # ls -lL <file referenced from aliases> Check the permissions for any paths referenced. If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-31404r1_fix

Remove the extended ACL from the file. # setfacl --remove-all <file referenced from aliases>

b

The SMTP service log file must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22442 - SV-37503r3_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN004510

Vuln IDs

V-22442

Rule IDs

SV-37503r3_rule

If the SMTP service log file has an extended ACL, unauthorized users may be allowed to access or to modify the log file.System Administrator

Checks: C-36160r4_chk

Depending on what system is used for log processing, either /etc/syslog.conf or /etc/rsyslog.conf will be the logging configuration file. Examine /etc/syslog.conf or /etc/rsyslog.conf and determine the log file(s) receiving logs for "mail.crit", "mail.debug", mail.*, or "*.crit". Procedure: This check is applicable to both Postfix and sendmail servers. Check the permissions on these log files.Identify any log files configured for "*.crit" and the "mail" service (excluding mail.none) and at any severity level. For syslog: # egrep "(\*.crit|mail\.[^n][^/]*)" /etc/syslog.conf|sed 's/^[^/]*//'|xargs ls -lL For rsyslog: # egrep "(\*.crit|mail\.[^n][^/]*)" /etc/rsyslog.conf|sed 's/^[^/]*//'|xargs ls -lL If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the ISSO, this is a finding.

Fix: F-31411r1_fix

This fix is applicable to both Postfix and sendmail servers. Remove the extended ACL from the file. # setfacl --remove-all <log file>

b

The ftpusers file must be group-owned by root, bin, sys, or system.

AC-6 - Medium - CCI-000225 - V-22444 - SV-37538r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN004930

Vuln IDs

V-22444

Rule IDs

SV-37538r1_rule

If the ftpusers file is not group-owned by root or a system group, an unauthorized user may modify the file to allow unauthorized accounts to use FTP.System AdministratorECLP-1

Checks: C-36196r1_chk

Check the group ownership of the ftpusers file. Procedure: # ls -lL /etc/ftpusers /etc/vsftpd.ftpusers /etc/vsftpd/ftpusers If the file is not group-owned by root, bin, sys, or system, this is a finding.

Fix: F-31454r1_fix

Change the group owner of the ftpusers file. Procedure: # chgrp root /etc/ftpusers /etc/vsftpd.ftpusers /etc/vsftpd/ftpusers

b

The ftpusers file must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22445 - SV-37544r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN004950

Vuln IDs

V-22445

Rule IDs

SV-37544r1_rule

Excessive permissions on the ftpusers file could permit unauthorized modification. Unauthorized modification could result in Denial of Service to authorized FTP users or permit unauthorized users to access the FTP service.System AdministratorECLP-1

Checks: C-36200r1_chk

Check the permissions of the /etc/ftpusers file. # ls -lL /etc/ftpusers /etc/vsftpd.ftpusers /etc/vsftpd/ftpusers If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-31459r1_fix

Remove the extended ACL from the file. # setfacl --remove-all /etc/ftpusers /etc/vsftpd.ftpusers /etc/vsftpd/ftpusers

b

The .Xauthority files must not have extended ACLs.

AC-6 - Medium - CCI-000225 - V-22446 - SV-37682r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN005190

Vuln IDs

V-22446

Rule IDs

SV-37682r1_rule

.Xauthority files ensure the user is authorized to access specific X Windows host. Extended ACLs may permit unauthorized modification of these files, which could lead to Denial of Service to authorized access or allow unauthorized access to be obtained.System AdministratorECLP-1

Checks: C-36869r2_chk

Check the file permissions for the .Xauthority files. These files will be located in user home directories. Procedure: # ls -la ~username |egrep "(\.Xauthority|\.xauth)" If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-31834r1_fix

Remove the extended ACL from the file. # setfacl --remove-all .Xauthority

b

The SNMP service must use only SNMPv3 or its successors.

AC-17 - Medium - CCI-001435 - V-22447 - SV-37692r1_rule

RMF Control

AC-17

Severity

M

CCI

CCI-001435

Version

GEN005305

Vuln IDs

V-22447

Rule IDs

SV-37692r1_rule

SNMP Versions 1 and 2 are not considered secure. Without the strong authentication and privacy provided by the SNMP Version 3 User-based Security Model (USM), an attacker or other unauthorized users may gain access to detailed system management information and use the information to launch attacks against the system.System AdministratorDCPP-1

Checks: C-36889r1_chk

Check the SNMP daemon is not configured to use the v1 or v2c security models. Procedure: Examine the default install location /etc/snmpd.conf or: # find / -name snmpd.conf # grep -E '(v1|v2c|community|com2sec)' <snmp.conf file> | grep -v '^#' If any configuration is found, this is a finding.

Fix: F-31966r1_fix

Edit /etc/snmpd.conf and remove references to the "v1", "v2c", "community", or "com2sec". Restart the SNMP service. # service snmpd restart

b

The SNMP service must require the use of a FIPS 140-2 approved cryptographic hash algorithm as part of its authentication and integrity methods.

AC-17 - Medium - CCI-001453 - V-22448 - SV-37693r1_rule

RMF Control

AC-17

Severity

M

CCI

Version

GEN005306

Vuln IDs

V-22448

Rule IDs

SV-37693r1_rule

The SNMP service must use SHA-1 or a FIPS 140-2 approved successor for authentication and integrity.System AdministratorDCNR-1

Checks: C-36890r1_chk

Verify the SNMP daemon uses SHA for SNMPv3 users. Procedure: Examine the default install location /etc/snmp/snmpd.conf or: # find / -name snmpd.conf # grep -v '^#' <snmpd.conf file> | grep -i createuser | grep -vi SHA If any line is present this is a finding.

Fix: F-31971r1_fix

Edit /etc/snmp/snmpd.conf and add the SHA keyword for any create user statement without one. Restart the SNMP service. # service snmpd restart

b

The SNMP service must require the use of a FIPS 140-2 approved encryption algorithm for protecting the privacy of SNMP messages.

AC-17 - Medium - CCI-000068 - V-22449 - SV-37695r1_rule

RMF Control

AC-17

Severity

M

CCI

Version

GEN005307

Vuln IDs

V-22449

Rule IDs

SV-37695r1_rule

The SNMP service must use AES or a FIPS 140-2 approved successor algorithm for protecting the privacy of communications.System AdministratorDCNR-1

Checks: C-36891r1_chk

Verify the SNMP daemon uses AES for SNMPv3 users. Procedure: Examine the default install location /etc/snmp/snmpd.conf or: # find / -name snmpd.conf # grep -v '^#' <snmpd.conf file> | grep -i createuser | grep -vi AES If any line is present this is a finding.

Fix: F-31986r1_fix

Edit /etc/snmp/snmpd.conf and add the AES keyword for any create user statement without one. Restart the SNMP service. # service snmpd restart

b

Management Information Base (MIB) files must not have extended ACLs.

AC-6 - Medium - CCI-000225 - V-22450 - SV-37700r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN005350

Vuln IDs

V-22450

Rule IDs

SV-37700r1_rule

The ability to read the MIB file could impart special knowledge to an intruder or malicious user about the ability to extract compromising information about the system or network.System AdministratorECLP-1

Checks: C-36895r1_chk

Check the file permissions for the MIB files. # find / -name *.mib # ls -lL <mib file> If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-32014r1_fix

Remove the extended ACL from the file. # setfacl --remove-all <mib file>

b

The snmpd.conf file must be group-owned by root, bin, sys, or system.

AC-6 - Medium - CCI-000225 - V-22451 - SV-37704r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN005365

Vuln IDs

V-22451

Rule IDs

SV-37704r1_rule

The snmpd.conf file contains authenticators and must be protected from unauthorized access and modification. If the file is not group-owned by a system group, it may be subject to access and modification from unauthorized users.System AdministratorECLP-1

Checks: C-36898r1_chk

Check the group ownership of the SNMP configuration file. Procedure: Examine the default install location /etc/snmp/snmpd.conf or: # find / -name snmpd.conf # ls -lL <snmpd.conf> If the file is not group-owned by root, bin, sys, or system, this is a finding.

Fix: F-32038r1_fix

Change the group ownership of the SNMP configuration file. Procedure: # chgrp root <snmpd.conf>

b

The snmpd.conf file must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22452 - SV-37706r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN005375

Vuln IDs

V-22452

Rule IDs

SV-37706r1_rule

The snmpd.conf file contains authenticators and must be protected from unauthorized access and modification.System AdministratorECLP-1

Checks: C-36900r1_chk

Check the permissions of the SNMP configuration file. Procedure: Examine the default install location /etc/snmp/snmpd.conf or: # find / -name snmpd.conf # ls -lL <snmpd.conf> If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-32047r1_fix

Remove the extended ACL from the file. # setfacl --remove-all <snmpd.conf file>

b

The /etc/syslog.conf file must have mode 0640 or less permissive.

AC-6 - Medium - CCI-000225 - V-22453 - SV-37709r2_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN005390

Vuln IDs

V-22453

Rule IDs

SV-37709r2_rule

Unauthorized users must not be allowed to access or modify the /etc/syslog.conf file.System Administrator

Checks: C-36907r2_chk

Check the permissions of the syslog configuration file. Depending on what system is used for log processing either /etc/syslog.conf or /etc/rsyslog.conf will be the logging configuration file. # ls -lL /etc/syslog.conf Or: # ls -lL /etc/rsyslog.conf If the mode of the file is more permissive than 0640, this is a finding.

Fix: F-32082r2_fix

Change the permissions of the syslog or rsyslog configuration file. # chmod 0640 /etc/syslog.conf Or: # chmod 0640 /etc/rsyslog.conf

b

The /etc/syslog.conf file must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22454 - SV-37710r2_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN005395

Vuln IDs

V-22454

Rule IDs

SV-37710r2_rule

Unauthorized users must not be allowed to access or modify the /etc/syslog.conf file.System Administrator

Checks: C-36909r2_chk

Check the permissions of the syslog configuration file. Depending on what system is used for log processing either /etc/syslog.conf or /etc/rsyslog.conf will be the logging configuration file. # ls -lL /etc/syslog.conf Or: # ls -lL /etc/rsyslog.conf If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-32087r2_fix

Remove the extended ACL from the file. # setfacl --remove-all /etc/syslog.conf Or: # setfacl -- remove-all /etc/rsyslog.conf

b

The system must use a remote syslog server (loghost).

AU-3 - Medium - CCI-000136 - V-22455 - SV-37811r2_rule

RMF Control

AU-3

Severity

M

CCI

CCI-000136

Version

GEN005450

Vuln IDs

V-22455

Rule IDs

SV-37811r2_rule

A syslog server (loghost) receives syslog messages from one or more systems. This data can be used as an authoritative log source in the event a system is compromised and its local logs are suspect.System Administrator

Checks: C-37012r2_chk

Check the syslog configuration file for remote syslog servers. Depending on what system is used for log processing either /etc/syslog.conf or /etc/rsyslog.conf will be the logging configuration file. # grep '@' /etc/syslog.conf | grep -v '^#' Or: # grep '@' /etc/rsyslog.conf | grep -v '^#' If no line is returned, this is a finding.

Fix: F-32277r2_fix

Edit the syslog or rsyslog configuration file and add an appropriate remote syslog server.

b

The SSH client must be configured to only use the SSHv2 protocol.

AC-17 - Medium - CCI-001436 - V-22456 - SV-37820r1_rule

RMF Control

AC-17

Severity

M

CCI

Version

GEN005501

Vuln IDs

V-22456

Rule IDs

SV-37820r1_rule

SSHv1 is not a DoD-approved protocol and has many well-known vulnerability exploits. Exploits of the SSH client could provide access to the system with the privileges of the user running the client.System AdministratorDCPP-1

Checks: C-37022r1_chk

Check the SSH client configuration for allowed protocol versions. # grep -i protocol /etc/ssh/ssh_config | grep -v '^#' If the returned protocol configuration allows versions less than 2, this is a finding.

Fix: F-32289r1_fix

Edit the /etc/ssh/ssh_config file and add or edit a "Protocol" configuration line not allowing versions less than 2.

b

The SSH daemon must only listen on management network addresses unless authorized for uses other than management.

AC-17 - Medium - CCI-000069 - V-22457 - SV-37823r2_rule

RMF Control

AC-17

Severity

M

CCI

CCI-000069

Version

GEN005504

Vuln IDs

V-22457

Rule IDs

SV-37823r2_rule

The SSH daemon should only listen on network addresses designated for management traffic. If the system has multiple network interfaces and SSH listens on addresses not designated for management traffic, the SSH service could be subject to unauthorized access. If SSH is used for purposes other than management, such as providing an SFTP service, the list of approved listening addresses may be documented.trueSystem Administrator

Checks: C-37024r2_chk

Ask the SA to identify which interfaces on the system are designated for management traffic. If all interfaces on the system are authorized for management traffic, this is not applicable. Check the SSH daemon configuration for listening network addresses. # grep -i Listen /etc/ssh/sshd_config | grep -v '^#' If no configuration is returned, or if a returned 'Listen' configuration contains addresses not designated for management traffic, this is a finding.

Fix: F-32292r2_fix

Edit the SSH daemon configuration to specify listening network addresses designated for management traffic. Restart the SSH daemon. # /sbin/service sshd restart

b

The SSH daemon must be configured to only use FIPS 140-2 approved ciphers.

AC-17 - Medium - CCI-000068 - V-22458 - SV-37824r3_rule

RMF Control

AC-17

Severity

M

CCI

Version

GEN005505

Vuln IDs

V-22458

Rule IDs

SV-37824r3_rule

DoD information systems are required to use FIPS 140-2 approved ciphers. SSHv2 ciphers meeting this requirement are 3DES and AES.System Administrator

Checks: C-37025r1_chk

Check the SSH daemon configuration for allowed ciphers. # grep -i ciphers /etc/ssh/sshd_config | grep -v '^#' If no lines are returned, or the returned ciphers list contains any cipher not starting with "3des" or "aes", this is a finding

Fix: F-32293r4_fix

Edit the SSH daemon configuration and remove any ciphers not starting with "3des" or "aes" and remove any ciphers ending with "cbc". If necessary, add a "Ciphers" line. Ciphers aes256-ctr,aes192-ctr,aes128-ctr Restart the SSH daemon. # /sbin/service sshd restart

b

The SSH daemon must be configured to not use Cipher-Block Chaining (CBC) ciphers.

CM-6 - Medium - CCI-000366 - V-22459 - SV-26752r2_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN005506

Vuln IDs

V-22459

Rule IDs

SV-26752r2_rule

The Cipher-Block Chaining (CBC) mode of encryption as implemented in the SSHv2 protocol is vulnerable to chosen plain text attacks and must not be used. System Administrator

Checks: C-27761r1_chk

Check the SSH daemon configuration for allowed ciphers. # grep -i ciphers /etc/ssh/sshd_config | grep -v '^#' If no lines are returned, or the returned ciphers list contains any cipher ending with cbc, this is a finding.

Fix: F-24001r2_fix

Edit /etc/ssh/sshd_config and add or edit the "Ciphers" line. Only include ciphers that start with "3des" or "aes" and do not contain "cbc". For the list of available ciphers for the particular version of your software, consult the sshd_config manpage. Restart the SSH daemon.

b

The SSH daemon must be configured to only use Message Authentication Codes (MACs) employing FIPS 140-2 approved cryptographic hash algorithms.

AC-17 - Medium - CCI-001453 - V-22460 - SV-37826r3_rule

RMF Control

AC-17

Severity

M

CCI

Version

GEN005507

Vuln IDs

V-22460

Rule IDs

SV-37826r3_rule

DoD information systems are required to use FIPS 140-2 approved cryptographic hash functions.System Administrator

Checks: C-37026r2_chk

Check the SSH daemon configuration for allowed MACs. Procedure: # grep -i macs /etc/ssh/sshd_config | grep -v '^#' If no lines are returned, or the returned MACs list contains any MAC that is not hmac-sha1 or a better hmac algorithm that is on the FIPS 140-2 approved list, this is a finding.

Fix: F-32294r3_fix

Edit the SSH daemon configuration and remove any MACs that are not hmac-sha1 or a better hmac algorithm that is on the FIPS 140-2 approved list. If necessary, add a MACs line. Restart the SSH daemon. # /sbin/service sshd restart

b

The SSH client must be configured to only use FIPS 140-2 approved ciphers.

AC-17 - Medium - CCI-000068 - V-22461 - SV-37828r1_rule

RMF Control

AC-17

Severity

M

CCI

Version

GEN005510

Vuln IDs

V-22461

Rule IDs

SV-37828r1_rule

DoD information systems are required to use FIPS 140-2 approved ciphers. SSHv2 ciphers meeting this requirement are 3DES and AES.System Administrator

Checks: C-37029r3_chk

Check the SSH client configuration for allowed ciphers. # grep -i ciphers /etc/ssh/ssh_config | grep -v '^#' If no lines are returned, or the returned ciphers list contains any cipher not starting with "3des" or "aes", this is a finding.

Fix: F-32297r2_fix

Edit the SSH client configuration and remove any ciphers not starting with "3des" or "aes" and remove any ciphers ending with "cbc". If necessary, add a "Ciphers" line.

b

The SSH client must be configured to not use Cipher-Block Chaining (CBC)-based ciphers.

CM-6 - Medium - CCI-000366 - V-22462 - SV-37830r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN005511

Vuln IDs

V-22462

Rule IDs

SV-37830r1_rule

The (CBC) mode of encryption as implemented in the SSHv2 protocol is vulnerable to chosen-plaintext attacks and must not be used. System AdministratorECSC-1

Checks: C-37030r1_chk

Check the SSH client configuration for allowed ciphers. # grep -i ciphers /etc/ssh/ssh_config | grep -v '^#' If no lines are returned, or the returned ciphers list contains any cipher ending with "cbc", this is a finding.

Fix: F-32298r2_fix

Edit the SSH client configuration and remove any ciphers not starting with "3des" or "aes" and remove any ciphers ending with "cbc". If necessary, add a "Ciphers" line.

b

The SSH client must be configured to only use Message Authentication Codes (MACs) employing FIPS 140-2 approved cryptographic hash algorithms.

AC-17 - Medium - CCI-001453 - V-22463 - SV-37836r2_rule

RMF Control

AC-17

Severity

M

CCI

Version

GEN005512

Vuln IDs

V-22463

Rule IDs

SV-37836r2_rule

DoD information systems are required to use FIPS 140-2 approved cryptographic hash functions.System Administrator

Checks: C-37033r2_chk

Check the SSH client configuration for allowed MACs. Procedure: # grep -i macs /etc/ssh/ssh_config | grep -v '^#' If no lines are returned, or the returned MACs list contains any MAC that is not hmac-sha1 or a better hmac algorithm that is on the FIPS 140-2 approved list, this is a finding.

Fix: F-32301r2_fix

Edit the SSH client configuration and remove any MACs that are not hmac-sha1 or a better hmac algorithm that is on the FIPS 140-2 approved list. If necessary, add a MACs line.

b

The SSH daemon must restrict login ability to specific users and/or groups.

AC-6 - Medium - CCI-000225 - V-22470 - SV-37843r2_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN005521

Vuln IDs

V-22470

Rule IDs

SV-37843r2_rule

Restricting SSH logins to a limited group of users, such as system administrators, prevents password-guessing and other SSH attacks from reaching system accounts and other accounts not authorized for SSH access.System Administrator

Checks: C-37041r1_chk

There are two ways in which access to SSH may restrict users or groups. Check if /etc/pam.d/sshd is configured to require daemon style login control. # grep pam_access.so /etc/pam.d/sshd|grep "required"|grep "account"| grep -v '^#' If no lines are returned, sshd is not configured to use pam_access. Check the SSH daemon configuration for the AllowGroups setting. # egrep -i "AllowGroups|AllowUsers" /etc/ssh/sshd_config | grep -v '^#' If no lines are returned, sshd is not configured to limit access to users/groups. If sshd is not configured to limit access either through pam_access or the use "AllowUsers" or "Allowgroups", this is a finding.

Fix: F-32309r2_fix

Edit the SSH daemon configuration and add an "AllowGroups" or "AllowUsers" directive specifying the groups and users allowed to have access. Restart the SSH daemon. # /sbin/service sshd restart Alternatively, modify the /etc/pam.d/sshd file to include the line account required pam_access.so accessfile=<path to access.conf for sshd> If the "accessfile" option is not specified the default "access.conf" file will be used. The "access.conf" file must contain the user restriction definitions.

b

The SSH public host key files must have mode 0644 or less permissive.

AC-6 - Medium - CCI-000225 - V-22471 - SV-37844r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN005522

Vuln IDs

V-22471

Rule IDs

SV-37844r1_rule

If a public host key file is modified by an unauthorized user, the SSH service may be compromised.System AdministratorECLP-1

Checks: C-37042r1_chk

Check the permissions for SSH public host key files. # ls -lL /etc/ssh/*key.pub If any file has a mode more permissive than 0644, this is a finding.

Fix: F-32310r1_fix

Change the permissions for the SSH public host key files. # chmod 0644 /etc/ssh/*key.pub

b

The SSH private host key files must have mode 0600 or less permissive.

AC-6 - Medium - CCI-000225 - V-22472 - SV-37863r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN005523

Vuln IDs

V-22472

Rule IDs

SV-37863r1_rule

If an unauthorized user obtains the private SSH host key file, the host could be impersonated.System AdministratorECLP-1

Checks: C-37075r1_chk

Check the permissions for SSH private host key files. # ls -lL /etc/ssh/*key If any file has a mode more permissive than 0600, this is a finding.

Fix: F-32347r1_fix

Change the permissions for the SSH private host key files. # chmod 0600 /etc/ssh/*key

a

The SSH daemon must not permit GSSAPI authentication unless needed.

CM-6 - Low - CCI-000366 - V-22473 - SV-37866r3_rule

RMF Control

CM-6

Severity

L

CCI

Version

GEN005524

Vuln IDs

V-22473

Rule IDs

SV-37866r3_rule

GSSAPI authentication is used to provide additional authentication mechanisms to applications. Allowing GSSAPI authentication through SSH exposes the system's GSSAPI to remote hosts, increasing the attack surface of the system. GSSAPI authentication must be disabled unless needed.System Administrator

Checks: C-37074r1_chk

Ask the SA if GSSAPI authentication is used for SSH authentication to the system. If so, this is not applicable. Check the SSH daemon configuration for the GSSAPIAuthentication setting. # grep -i GSSAPIAuthentication /etc/ssh/sshd_config | grep -v '^#' If no lines are returned, or the setting is set to "yes", this is a finding.

Fix: F-32342r2_fix

Edit the SSH daemon configuration and set (add if necessary) a "GSSAPIAuthentication" directive set to "no". Restart the SSH daemon. # /sbin/service sshd restart

a

The SSH client must not permit GSSAPI authentication unless needed.

CM-6 - Low - CCI-000366 - V-22474 - SV-37868r2_rule

RMF Control

CM-6

Severity

L

CCI

Version

GEN005525

Vuln IDs

V-22474

Rule IDs

SV-37868r2_rule

GSSAPI authentication is used to provide additional authentication mechanisms to applications. Allowing GSSAPI authentication through SSH exposes the system's GSSAPI to remote hosts, increasing the attack surface of the system. GSSAPI authentication must be disabled unless needed.System Administrator

Checks: C-37084r1_chk

The default setting for GSSAPIAuthentication is "no" . Check for a change from the default. # grep -i GSSAPIAuthentication /etc/ssh/ssh_config | grep -v '^#' If the setting is "yes" this is a finding.

Fix: F-32356r1_fix

Edit the SSH client configuration and set the GSSAPIAuthentication" directive set to "no".

a

The SSH daemon must not permit Kerberos authentication unless needed.

CM-6 - Low - CCI-000366 - V-22475 - SV-37872r2_rule

RMF Control

CM-6

Severity

L

CCI

Version

GEN005526

Vuln IDs

V-22475

Rule IDs

SV-37872r2_rule

Kerberos authentication for SSH is often implemented using GSSAPI. If Kerberos is enabled through SSH, the SSH daemon provides a means of access to the system's Kerberos implementation. Vulnerabilities in the system's Kerberos implementation may then be subject to exploitation. To reduce the attack surface of the system, the Kerberos authentication mechanism within SSH must be disabled for systems not using this capability. System Administrator

Checks: C-37088r1_chk

Ask the SA if Kerberos authentication is used by the system. If it is, this is not applicable. Check the SSH daemon configuration for the KerberosAuthentication setting. # grep -i KerberosAuthentication /etc/ssh/sshd_config | grep -v '^#' If no lines are returned, or the setting is set to "yes", this is a finding.

Fix: F-32363r2_fix

Edit the SSH daemon configuration and set (add if necessary) the "KerberosAuthentication" directive set to "no". Restart the SSH daemon. # /sbin/service sshd restart

b

The SSH daemon must perform strict mode checking of home directory configuration files.

AC-6 - Medium - CCI-000225 - V-22485 - SV-37900r2_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN005536

Vuln IDs

V-22485

Rule IDs

SV-37900r2_rule

If other users have access to modify user-specific SSH configuration files, they may be able to log into the system as another user.System Administrator

Checks: C-37126r1_chk

Check the SSH daemon configuration for the StrictModes setting. # grep -i StrictModes /etc/ssh/sshd_config | grep -v '^#' If the setting is not present, or not set to "yes", this is a finding.

Fix: F-32394r2_fix

Edit the SSH daemon configuration and add or edit the "StrictModes" setting value to "yes". Restart the SSH daemon. # /sbin/service sshd restart

b

The SSH daemon must use privilege separation.

AC-6 - Medium - CCI-000225 - V-22486 - SV-37904r2_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN005537

Vuln IDs

V-22486

Rule IDs

SV-37904r2_rule

SSH daemon privilege separation causes the SSH process to drop root privileges when not needed, which would decrease the impact of software vulnerabilities in the unprivileged section.System Administrator

Checks: C-37130r1_chk

Check the SSH daemon configuration for the UsePrivilegeSeparation setting. # grep -i UsePrivilegeSeparation /etc/ssh/sshd_config | grep -v '^#' If the setting is not present, or not set to "yes", this is a finding.

Fix: F-32398r2_fix

Edit the SSH daemon configuration and add or edit the "UsePrivilegeSeparation" setting value to "yes". Restart the SSH daemon. # /sbin/service sshd restart

b

The SSH daemon must not allow rhosts RSA authentication.

CM-6 - Medium - CCI-000366 - V-22487 - SV-37905r2_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN005538

Vuln IDs

V-22487

Rule IDs

SV-37905r2_rule

If SSH permits rhosts RSA authentication, a user may be able to log in based on the keys of the host originating the request and not any user-specific authentication.System Administrator

Checks: C-37131r1_chk

Check the SSH daemon configuration for the RhostsRSAAuthentication setting. # grep -i RhostsRSAAuthentication /etc/ssh/sshd_config | grep -v '^#' If the setting is set to "yes", this is a finding.

Fix: F-32399r2_fix

Edit the SSH daemon configuration and add or edit the "RhostsRSAAuthentication" setting value to "no". Restart the SSH daemon. # /sbin/service sshd restart

b

The SSH daemon must not allow compression or must only allow compression after successful authentication.

CM-6 - Medium - CCI-000366 - V-22488 - SV-37908r2_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN005539

Vuln IDs

V-22488

Rule IDs

SV-37908r2_rule

If compression is allowed in an SSH connection prior to authentication, vulnerabilities in the compression software could result in compromise of the system from an unauthenticated connection, potentially with root privileges.System Administrator

Checks: C-37134r1_chk

Check the SSH daemon configuration for the compression setting. # grep -i Compression /etc/ssh/sshd_config | egrep "no|delayed" If the setting is missing or is commented out, this is a finding. If the setting is present but is not set to "no" or "delayed", this is a finding.

Fix: F-32403r2_fix

Edit the SSH daemon configuration and add or edit the "Compression" setting value to "no" or "delayed". Restart the SSH daemon. # /sbin/service sshd restart

b

The SSH daemon must be configured with the Department of Defense (DoD) logon banner.

AC-8 - Medium - CCI-000048 - V-22489 - SV-37915r3_rule

RMF Control

AC-8

Severity

M

CCI

Version

GEN005550

Vuln IDs

V-22489

Rule IDs

SV-37915r3_rule

Failure to display the DoD logon banner prior to a logon attempt will negate legal proceedings resulting from unauthorized access to system resources. The SSH service must be configured to display the DoD logon warning banner either through the SSH configuration or a wrapper program such as TCP_WRAPPERS. The SSH daemon may also be used to provide SFTP service. The warning banner configuration for SSH will apply to SFTP.System Administrator

Checks: C-37141r2_chk

Verify the SSH daemon is configured for logon warning banners. Procedure: An exact match is required to have a valid warning banner. Check for the following login banner. You are accessing a U.S. Government (USG) Information System (IS) that is provided for USG-authorized use only. By using this IS (which includes any device attached to this IS), you consent to the following conditions: -The USG routinely intercepts and monitors communications on this IS for purposes including, but not limited to, penetration testing, COMSEC monitoring, network operations and defense, personnel misconduct (PM), law enforcement (LE), and counterintelligence (CI) investigations. -At any time, the USG may inspect and seize data stored on this IS. -Communications using, or data stored on, this IS are not private, are subject to routine monitoring, interception, and search, and may be disclosed or used for any USG-authorized purpose. -This IS includes security measures (e.g., authentication and access controls) to protect USG interests--not for your personal benefit or privacy. -Notwithstanding the above, using this IS does not constitute consent to PM, LE or CI investigative searching or monitoring of the content of privileged communications, or work product, related to personal representation or services by attorneys, psychotherapists, or clergy, and their assistants. Such communications and work product are private and confidential. See User Agreement for details. OR I've read & consent to terms in IS user agreem't.

Fix: F-32408r3_fix

Edit /etc/issue and the DoD login banner. DoD Login Banners: You are accessing a U.S. Government (USG) Information System (IS) that is provided for USG-authorized use only. By using this IS (which includes any device attached to this IS), you consent to the following conditions: -The USG routinely intercepts and monitors communications on this IS for purposes including, but not limited to, penetration testing, COMSEC monitoring, network operations and defense, personnel misconduct (PM), law enforcement (LE), and counterintelligence (CI) investigations. -At any time, the USG may inspect and seize data stored on this IS. -Communications using, or data stored on, this IS are not private, are subject to routine monitoring, interception, and search, and may be disclosed or used for any USG-authorized purpose. -This IS includes security measures (e.g., authentication and access controls) to protect USG interests- -not for your personal benefit or privacy. -Notwithstanding the above, using this IS does not constitute consent to PM, LE or CI investigative searching or monitoring of the content of privileged communications, or work product, related to personal representation or services by attorneys, psychotherapists, or clergy, and their assistants. Such communications and work product are private and confidential. See User Agreement for details. OR I've read & consent to terms in IS user agreem't. Find the location of the banner file for sshd and examine the content: # grep -i banner /etc/ssh/sshd_config | grep -v '^#' # cat Edit the SSH daemon configuration and add or edit a "Banner" setting referencing a file containing a logon warning banner. Restart the SSH daemon. # /sbin/service sshd restart

b

The system must be configured with a default gateway for IPv6 if the system uses IPv6, unless the system is a router.

CM-6 - Medium - CCI-000366 - V-22490 - SV-37921r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN005570

Vuln IDs

V-22490

Rule IDs

SV-37921r1_rule

If a system has no default gateway defined, the system is at increased risk of man-in-the-middle, monitoring, and Denial of Service attacks.System AdministratorECSC-1

Checks: C-37153r1_chk

Check for a default route for IPv6. If the system is a VM host and acts as a router solely for the benefit of its client systems, then this rule is not applicable. # ip -6 route list | grep default If the system uses IPv6, and no results are returned, this is a finding.

Fix: F-24048r1_fix

Add a default route for IPv6. Edit /etc/sysconfig/network-scripts/ifcfg-eth0 (substitute interface as appropriate). Add an IPV6_DEFAULTGW=<gateway> configuration setting. Restart the interface. # ifdown eth0; ifup eth0

b

The system must not have IP forwarding for IPv6 enabled, unless the system is an IPv6 router.

CM-6 - Medium - CCI-000366 - V-22491 - SV-37930r2_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN005610

Vuln IDs

V-22491

Rule IDs

SV-37930r2_rule

If the system is configured for IP forwarding and is not a designated router, it could be used to bypass network security by providing a path for communication not filtered by network devices.System Administrator

Checks: C-37186r3_chk

Check if the system is configured for IPv6 forwarding. # grep [01] /proc/sys/net/ipv6/conf/*/forwarding|egrep "default|all" If the /proc/sys/net/ipv6/conf/*/forwarding entries do not exist because of compliance with GEN007720, this is not a finding. If all of the resulting lines do not end with 0, this is a finding.

Fix: F-32423r1_fix

Disable IPv6 forwarding. Edit /etc/sysctl.conf and add a setting for "net.ipv6.conf.all.forwarding=0" and "net.ipv6.conf.default.forwarding=0". Reload the sysctls. Procedure: # sysctl -p

b

The Network File System (NFS) export configuration file must be group-owned by root, bin, sys, or system.

AC-6 - Medium - CCI-000225 - V-22492 - SV-37940r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN005750

Vuln IDs

V-22492

Rule IDs

SV-37940r1_rule

Failure to give group-ownership of the NFS export configuration file to root or a system group provides the designated group-owner and possible unauthorized users with the potential to change system configuration which could weaken the system's security posture.System AdministratorECLP-1

Checks: C-37213r1_chk

Check the group ownership of the NFS export configuration file. Procedure: # ls -lL /etc/exports If the file is not group-owned by root, bin, sys, or system, this is a finding.

Fix: F-32431r1_fix

Change the group ownership of the NFS export configuration file. Procedure: # chgrp root /etc/exports

a

The Network File System (NFS) exports configuration file must not have an extended ACL.

AC-6 - Low - CCI-000225 - V-22493 - SV-37947r1_rule

RMF Control

AC-6

Severity

L

CCI

Version

GEN005770

Vuln IDs

V-22493

Rule IDs

SV-37947r1_rule

File system extended ACLs provide access to files beyond what is allowed by the mode numbers of the files. Excessive permissions on the NFS export configuration file could allow unauthorized modification of the file, which could result in Denial of Service to authorized NFS exports and the creation of additional unauthorized exports.System AdministratorECLP-1

Checks: C-37232r1_chk

Check the permissions of the NFS export configuration file. # ls -lL /etc/exports If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-32439r1_fix

Remove the extended ACL from the file. # setfacl --remove-all /etc/exports

b

All Network File System (NFS) exported system files and system directories must be group-owned by root, bin, sys, or system.

AC-6 - Medium - CCI-000225 - V-22496 - SV-37851r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN005810

Vuln IDs

V-22496

Rule IDs

SV-37851r1_rule

Failure to give group-ownership of sensitive files or directories to root provides the members of the owning group with the potential to access sensitive information or change system configuration which could weaken the system's security posture.System AdministratorECLP-1

Checks: C-37046r1_chk

List the exports. # cat /etc/exports For each file system displayed, check the ownership. # ls -ldL <exported file system path> If the directory is not group-owned by root, bin, sys, or system, this is a finding.

Fix: F-32314r1_fix

Change the group owner of the export directory. # chgrp root <export>

b

The /etc/smb.conf file must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22497 - SV-37877r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN006150

Vuln IDs

V-22497

Rule IDs

SV-37877r1_rule

Excessive permissions could endanger the security of the Samba configuration file and, ultimately, the system and network.System AdministratorECLP-1

Checks: C-37098r1_chk

Check the permissions of the Samba configuration file. # ls -lL /etc/samba/smb.conf If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-32372r1_fix

Remove the extended ACL from the file. # setfacl --remove-all /etc/samba/smb.conf

b

The /etc/smbpasswd file must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22498 - SV-37884r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN006210

Vuln IDs

V-22498

Rule IDs

SV-37884r1_rule

If the permissions of the "smbpasswd" file are too permissive, it may be maliciously accessed or modified, potentially resulting in the compromise of Samba accounts.System AdministratorECLP-1

Checks: C-37109r1_chk

Check the permissions of the Samba password files. Procedure: # ls -lL /etc/samba/passdb.tdb /etc/samba/secrets.tdb If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-32377r1_fix

Remove the extended ACL from the file. # setfacl --remove-all /etc/samba/passdb.tdb /etc/samba/secrets.tdb

b

Samba must be configured to use an authentication mechanism other than "share."

CM-6 - Medium - CCI-000366 - V-22499 - SV-37891r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN006225

Vuln IDs

V-22499

Rule IDs

SV-37891r1_rule

Samba share authentication does not provide for individual user identification and must not be used.System AdministratorECSC-1

Checks: C-37117r1_chk

Check the security mode of the Samba configuration. # grep -i security /etc/samba/smb.conf If the security mode is "share", this is a finding.

Fix: F-32385r1_fix

Edit the "/etc/samba/smb.conf" file and change the "security" setting to "user" or another valid setting other than "share".

b

Samba must be configured to use encrypted passwords.

CM-6 - Medium - CCI-000366 - V-22500 - SV-37894r2_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN006230

Vuln IDs

V-22500

Rule IDs

SV-37894r2_rule

Samba must be configured to protect authenticators. If Samba passwords are not encrypted for storage, plain-text user passwords may be read by those with access to the Samba password file.System Administrator

Checks: C-37120r3_chk

If the "samba-common" package is not installed, this is not applicable. Check the encryption setting of Samba. # grep -i 'encrypt passwords' /etc/samba/smb.conf If the setting is not present, or not set to 'yes', this is a finding.

Fix: F-32388r1_fix

Edit the "/etc/samba/smb.conf" file and change the "encrypt passwords" setting to "yes".

b

Samba must be configured to not allow guest access to shares.

CM-6 - Medium - CCI-000366 - V-22501 - SV-37896r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN006235

Vuln IDs

V-22501

Rule IDs

SV-37896r1_rule

Guest access to shares permits anonymous access and is not permitted.System AdministratorECSC-1

Checks: C-37122r1_chk

Check the access to shares for Samba. # grep -i 'guest ok' /etc/samba/smb.conf If the setting exists and is set to 'yes', this is a finding.

Fix: F-32390r1_fix

Edit the "/etc/samba/smb.conf" file and change the "guest ok" setting to "no".

b

The /etc/news/incoming.conf file must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22502 - SV-37902r2_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN006270

Vuln IDs

V-22502

Rule IDs

SV-37902r2_rule

File system extended ACLs provide access to files beyond what is allowed by the mode numbers of the files. Excessive permissions on the "incoming.conf" file may allow unauthorized modification which could lead to Denial of Service to authorized users or provide access to unauthorized users.System Administrator

Checks: C-37128r2_chk

Check the permissions of the file. # ls -lL /etc/news/incoming.conf If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-32396r2_fix

Remove the extended ACL from the file. # setfacl --remove-all /etc/news/incoming.conf

b

The /etc/news/hosts.nntp.nolimit file must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22503 - SV-37713r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN006290

Vuln IDs

V-22503

Rule IDs

SV-37713r1_rule

File system extended ACLs provide access to files beyond what is allowed by the mode numbers of the files. Excessive permissions on the hosts.nntp.nolimit file may allow unauthorized modification which could lead to Denial of Service to authorized users or provide access to unauthorized users.System AdministratorECLP-1

Checks: C-36914r1_chk

Check the permissions for "/etc/news/hosts.nntp.nolimit". # ls -lL /etc/news/hosts.nntp.nolimit If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-32132r1_fix

Remove the extended ACL from the file. # setfacl --remove-all /etc/news/hosts.nntp.nolimit

b

The /etc/news/nnrp.access file must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22504 - SV-37730r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN006310

Vuln IDs

V-22504

Rule IDs

SV-37730r1_rule

File system extended ACLs provide access to files beyond what is allowed by the mode numbers of the files. Excessive permissions on the nnrp.access file may allow unauthorized modification which could lead to Denial of Service to authorized users or provide access to unauthorized users.System AdministratorECLP-1

Checks: C-36926r1_chk

Check the permissions of the file. # ls -lL /etc/news/nnrp.access If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-32191r1_fix

Remove the extended ACL from the file. # setfacl --remove-all /etc/news/nnrp.access

b

The /etc/news/passwd.nntp file must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22505 - SV-37733r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN006330

Vuln IDs

V-22505

Rule IDs

SV-37733r1_rule

Extended ACLs may provide excessive permissions on the /etc/news/passwd.nntp file, which may permit unauthorized access or modification to the NNTP configuration.System AdministratorECLP-1

Checks: C-36929r1_chk

Check the permissions of the file. # ls -lL /etc/news/passwd.nntp If the mode includes a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-32194r1_fix

Remove the extended ACL from the file. # setfacl --remove-all /etc/news/passwd.nntp

b

The system package management tool must be used to verify system software periodically.

CM-6 - Medium - CCI-000366 - V-22506 - SV-37751r2_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN006565

Vuln IDs

V-22506

Rule IDs

SV-37751r2_rule

Verification using the system package management tool can be used to determine that system software has not been tampered with. This requirement is not applicable to systems not using package management tools.System AdministratorECAT-1

Checks: C-36948r3_chk

Check the root crontab (crontab -l) and the global crontabs in "/etc/crontab", "/etc/cron.*" for the presence of an rpm verification command such as: rpm -qVa | awk '$2!="c" {print $0}' If no such cron job is found, this is a finding. If the result of the cron job indicates packages which do not pass verification exist, this is a finding unless the changes were made due to another STIG entry.

Fix: F-32212r1_fix

Add a cron job to run an rpm verification command such as: rpm -qVa | awk '$2!="c" {print $0}' For packages which failed verification: If the package is not necessary for operations, remove it from the system. If the package is necessary for operations, re-install the package.

a

The file integrity tool must be configured to verify ACLs.

SI-7 - Low - CCI-001297 - V-22507 - SV-37752r1_rule

RMF Control

SI-7

Severity

L

CCI

CCI-001297

Version

GEN006570

Vuln IDs

V-22507

Rule IDs

SV-37752r1_rule

ACLs can provide permissions beyond those permitted through the file mode and must be verified by file integrity tools.System AdministratorECAT-1

Checks: C-36950r1_chk

If using an Advanced Intrusion Detection Environment (AIDE), verify that the configuration contains the "ACL" option for all monitored files and directories. Procedure: Check for the default location /etc/aide/aide.conf or: # find / -name aide.conf # egrep "[+]?acl" <aide.conf file> If the option is not present. This is a finding. If using a different file integrity tool, check the configuration per tool documentation.

Fix: F-32214r1_fix

If using AIDE, edit the configuration and add the "ACL" option for all monitored files and directories. If using a different file integrity tool, configure ACL checking per the tool's documentation.

a

The file integrity tool must be configured to verify extended attributes.

SI-7 - Low - CCI-001297 - V-22508 - SV-37753r1_rule

RMF Control

SI-7

Severity

L

CCI

CCI-001297

Version

GEN006571

Vuln IDs

V-22508

Rule IDs

SV-37753r1_rule

Extended attributes in file systems are used to contain arbitrary data and file metadata with security implications.System AdministratorECAT-1

Checks: C-36951r1_chk

If using an Advanced Intrusion Detection Environment (AIDE), verify the configuration contains the "xattrs" option for all monitored files and directories. Procedure: Check for the default location /etc/aide/aide.conf or: # find / -name aide.conf # egrep "[+]?xattrs" <aide.conf file> If the option is not present. This is a finding. If using a different file integrity tool, check the configuration per tool documentation.

Fix: F-32215r1_fix

If using AIDE, edit the configuration and add the "xattrs" option for all monitored files and directories. If using a different file integrity tool, configure extended attributes checking per the tool's documentation.

a

The file integrity tool must use FIPS 140-2 approved cryptographic hashes for validating file contents.

SI-7 - Low - CCI-001297 - V-22509 - SV-37754r1_rule

RMF Control

SI-7

Severity

L

CCI

CCI-001297

Version

GEN006575

Vuln IDs

V-22509

Rule IDs

SV-37754r1_rule

File integrity tools often use cryptographic hashes for verifying that file contents have not been altered. These hashes must be FIPS 140-2 approved.System AdministratorECSC-1

Checks: C-36952r1_chk

If using an Advanced Intrusion Detection Environment (AIDE), verify the configuration contains the "sha256" or "sha512" options for all monitored files and directories. Procedure: Check for the default location /etc/aide/aide.conf or: # find / -name aide.conf # egrep "[+]?(sha256|sha512)" <aide.conf file> If the option is not present. This is a finding. If one of these options is not present. This is a finding. If using a different file integrity tool, check the configuration per tool documentation.

Fix: F-32217r1_fix

If using AIDE, edit the configuration and add the "sha512" option for all monitored files and directories. If using a different file integrity tool, configure FIPS 140-2 approved cryptographic hashes per the tool's documentation.

b

The Stream Control Transmission Protocol (SCTP) must be disabled unless required.

CM-7 - Medium - CCI-000382 - V-22511 - SV-37761r1_rule

RMF Control

CM-7

Severity

M

CCI

Version

GEN007020

Vuln IDs

V-22511

Rule IDs

SV-37761r1_rule

The Stream Control Transmission Protocol (SCTP) is an Internet Engineering Task Force (IETF)-standardized transport layer protocol. This protocol is not yet widely used. Binding this protocol to the network stack increases the attack surface of the host. Unprivileged local processes may be able to cause the system to dynamically load a protocol handler by opening a socket using the protocol.System AdministratorECSC-1

Checks: C-36957r1_chk

Verify the SCTP protocol handler is prevented from dynamic loading. # grep 'install sctp /bin/true' /etc/modprobe.conf /etc/modprobe.d/* If no result is returned, this is a finding.

Fix: F-32222r1_fix

Prevent the SCTP protocol handler for dynamic loading. # echo "install sctp /bin/true" >> /etc/modprobe.conf

b

The Datagram Congestion Control Protocol (DCCP) must be disabled unless required.

CM-7 - Medium - CCI-000382 - V-22514 - SV-37763r1_rule

RMF Control

CM-7

Severity

M

CCI

Version

GEN007080

Vuln IDs

V-22514

Rule IDs

SV-37763r1_rule

The DCCP is a proposed transport layer protocol. This protocol is not yet widely used. Binding this protocol to the network stack increases the attack surface of the host. Unprivileged local processes may be able to cause the system to dynamically load a protocol handler by opening a socket using the protocol.System AdministratorECSC-1

Checks: C-36958r1_chk

Verify the DCCP protocol handler is prevented from dynamic loading. # grep 'install dccp /bin/true' /etc/modprobe.conf /etc/modprobe.d/* If no result is returned, this is a finding. # grep 'install dccp_ipv4 /bin/true' /etc/modprobe.conf /etc/modprobe.d/* If no result is returned, this is a finding. # grep 'install dccp_ipv6 /bin/true' /etc/modprobe.conf /etc/modprobe.d/* If no result is returned, this is a finding.

Fix: F-32223r1_fix

Prevent the DCCP protocol handler for dynamic loading. # echo "install dccp /bin/true" >> /etc/modprobe.conf # echo "install dccp_ipv4 /bin/true" >> /etc/modprobe.conf # echo "install dccp_ipv6 /bin/true" >> /etc/modprobe.conf

b

The AppleTalk protocol must be disabled or not installed.

CM-7 - Medium - CCI-000382 - V-22524 - SV-26887r1_rule

RMF Control

CM-7

Severity

M

CCI

Version

GEN007260

Vuln IDs

V-22524

Rule IDs

SV-26887r1_rule

The AppleTalk suite of protocols is no longer in common use. Binding this protocol to the network stack increases the attack surface of the host. Unprivileged local processes may be able to cause the system to dynamically load a protocol handler by opening a socket using the protocol.System AdministratorECSC-1

Checks: C-27846r1_chk

Verify the AppleTalk protocol handler is prevented from dynamic loading. # grep 'install appletalk' /etc/modprobe.conf /etc/modprobe.d/* If anything is returned check that appletalk is disabled by having the executable set to '/bin/true'. If an uncommented line containing "appletalk" is found which has not been disabled, this is a finding.

Fix: F-24130r1_fix

Prevent the AppleTalk protocol handler for dynamic loading. # echo "install appletalk /bin/true" >> /etc/modprobe.conf

b

The Reliable Datagram Sockets (RDS) protocol must be disabled or not installed unless required.

CM-7 - Medium - CCI-000382 - V-22530 - SV-37603r1_rule

RMF Control

CM-7

Severity

M

CCI

Version

GEN007480

Vuln IDs

V-22530

Rule IDs

SV-37603r1_rule

The RDS protocol is a relatively new protocol developed by Oracle for communication between the nodes of a cluster. Binding this protocol to the network stack increases the attack surface of the host. Unprivileged local processes may be able to cause the system to dynamically load a protocol handler by opening a socket using the protocol.System AdministratorECSC-1

Checks: C-36740r1_chk

Ask the SA if RDS is required by application software running on the system. If so, this is not applicable. Verify the RDS protocol handler is prevented from dynamic loading. # grep 'install rds /bin/true' /etc/modprobe.conf /etc/modprobe.d/* If no result is returned, this is a finding.

Fix: F-31638r1_fix

Prevent the RDS protocol handler for dynamic loading. # echo "install rds /bin/true" >> /etc/modprobe.conf

b

The Transparent Inter-Process Communication (TIPC) protocol must be disabled or uninstalled.

CM-7 - Medium - CCI-000382 - V-22533 - SV-37604r1_rule

RMF Control

CM-7

Severity

M

CCI

Version

GEN007540

Vuln IDs

V-22533

Rule IDs

SV-37604r1_rule

The TIPC protocol is a relatively new cluster communications protocol developed by Ericsson. Binding this protocol to the network stack increases the attack surface of the host. Unprivileged local processes may be able to cause the system to dynamically load a protocol handler by opening a socket using the protocol.System AdministratorECSC-1

Checks: C-36758r1_chk

Verify the TIPC protocol handler is prevented from dynamic loading. # grep 'install tipc /bin/true' /etc/modprobe.conf /etc/modprobe.d/* If no result is returned, this is a finding.

Fix: F-31639r1_fix

Prevent the TIPC protocol handler for dynamic loading. # echo "install tipc /bin/true" >> /etc/modprobe.conf

b

The Bluetooth protocol handler must be disabled or not installed.

AC-4 - Medium - CCI-001551 - V-22539 - SV-37605r1_rule

RMF Control

AC-4

Severity

M

CCI

Version

GEN007660

Vuln IDs

V-22539

Rule IDs

SV-37605r1_rule

Bluetooth is a Personal Area Network (PAN) technology. Binding this protocol to the network stack increases the attack surface of the host. Unprivileged local processes may be able to cause the kernel to dynamically load a protocol handler by opening a socket using the protocol.System AdministratorECSC-1

Checks: C-36766r1_chk

Verify the Bluetooth protocol handler is prevented from dynamic loading. # grep 'install bluetooth /bin/true' /etc/modprobe.conf /etc/modprobe.d/* If no result is returned, this is a finding.

Fix: F-31640r1_fix

Prevent the Bluetooth protocol handler for dynamic loading. # echo "install bluetooth /bin/true" >> /etc/modprobe.conf

b

The IPv6 protocol handler must not be bound to the network stack unless needed.

AC-4 - Medium - CCI-001551 - V-22541 - SV-37606r1_rule

RMF Control

AC-4

Severity

M

CCI

Version

GEN007700

Vuln IDs

V-22541

Rule IDs

SV-37606r1_rule

IPv6 is the next version of the Internet protocol. Binding this protocol to the network stack increases the attack surface of the host.System AdministratorECSC-1

Checks: C-36779r1_chk

If the IPv6 protocol handler is bound to the network stack, and the system does not need IPv6, this is a finding. # grep NETWORKING_IPV6 /etc/sysconfig/network If the line is set to "yes", this is a finding.

Fix: F-31643r1_fix

Remove the capability to use IPv6 protocol handler. Procedure: Edit /etc/sysconfig/network and change NETWORKING_IPV6=yes to NETWORKING_IPV6=no Edit /etc/modprobe.conf and add these lines (if they are not in it): alias net-pf-10 off alias ipv6 off Stop the ipv6tables service by typing: service ip6tables stop Disable the ipv6tables service by typing: chkconfig ip6tables off Remove the ipv6 kernel module # rmmod ipv6 Reboot

b

The IPv6 protocol handler must be prevented from dynamic loading unless needed.

AC-4 - Medium - CCI-001551 - V-22542 - SV-37609r1_rule

RMF Control

AC-4

Severity

M

CCI

Version

GEN007720

Vuln IDs

V-22542

Rule IDs

SV-37609r1_rule

IPv6 is the next generation of the Internet protocol. Binding this protocol to the network stack increases the attack surface of the host. Unprivileged local processes may be able to cause the system to dynamically load a protocol handler by opening a socket using the protocol.System AdministratorECSC-1

Checks: C-36786r1_chk

If this system uses IPv6, this is not applicable. Verify the IPv6 protocol handler is prevented from dynamic loading. # grep 'install ipv6 /bin/true' /etc/modprobe.conf /etc/modprobe.d/* If no result is returned, this is a finding.

Fix: F-31644r1_fix

Prevent the IPv6 protocol handler for dynamic loading. # echo "install ipv6 /bin/true" >> /etc/modprobe.conf

b

The system must not have 6to4 enabled.

AC-4 - Medium - CCI-001551 - V-22545 - SV-37610r1_rule

RMF Control

AC-4

Severity

M

CCI

Version

GEN007780

Vuln IDs

V-22545

Rule IDs

SV-37610r1_rule

6to4 is an IPv6 transition mechanism involving tunneling IPv6 packets encapsulated in IPv4 packets on an ad-hoc basis. This is not a preferred transition strategy and increases the attack surface of the system.System AdministratorECSC-1

Checks: C-36796r1_chk

Check the system for any active 6to4 tunnels without specific remote addresses. # ip tun list | grep "remote any" | grep "ipv6/ip" If any results are returned the "tunnel" is the first field. If any results are returned, this is a finding.

Fix: F-31646r1_fix

Disable the active 6to4 tunnel. # ip link set <tunnel> down Add this command to a startup script, or remove the configuration creating the tunnel.

b

The system must not have Teredo enabled.

AC-4 - Medium - CCI-001551 - V-22546 - SV-37611r1_rule

RMF Control

AC-4

Severity

M

CCI

Version

GEN007800

Vuln IDs

V-22546

Rule IDs

SV-37611r1_rule

Teredo is an IPv6 transition mechanism involving tunneling IPv6 packets encapsulated in IPv4 packets. Unauthorized tunneling may circumvent network security.System AdministratorECSC-1

Checks: C-36805r1_chk

Verify the Miredo service is not running. # ps ax | grep miredo | grep -v grep If the miredo process is running, this is a finding.

Fix: F-31647r1_fix

Edit startup scripts to prevent the service from running on startup.

b

The system must not have IP tunnels configured.

AC-4 - Medium - CCI-001551 - V-22547 - SV-37613r1_rule

RMF Control

AC-4

Severity

M

CCI

Version

GEN007820

Vuln IDs

V-22547

Rule IDs

SV-37613r1_rule

IP tunneling mechanisms can be used to bypass network filtering.System AdministratorECSC-1

Checks: C-36809r1_chk

Check for any IP tunnels. # ip tun list # ip -6 tun list If any tunnels are listed, this is a finding.

Fix: F-31648r1_fix

Remove the tunnels. # ip tun del <tunnel> Edit system startup scripts to prevent tunnel creation on startup.

b

The DHCP client must be disabled if not needed.

CM-6 - Medium - CCI-000366 - V-22548 - SV-37615r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN007840

Vuln IDs

V-22548

Rule IDs

SV-37615r1_rule

DHCP allows for the unauthenticated configuration of network parameters on the system by exchanging information with a DHCP server.System AdministratorECSC-1

Checks: C-36811r1_chk

Verify no interface is configured to use DHCP. # grep -i bootproto=dhcp /etc/sysconfig/network-scripts/ifcfg-* If any configuration is found, this is a finding.

Fix: F-24173r1_fix

Edit the "/etc/sysconfig/network-scripts/ifcfg-*" file(s) and change the "bootproto" setting to "static".

b

The DHCP client must not send dynamic DNS updates.

CM-6 - Medium - CCI-000366 - V-22549 - SV-26933r2_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN007850

Vuln IDs

V-22549

Rule IDs

SV-26933r2_rule

Dynamic DNS updates transmit unencrypted information about a system including its name and address and should not be used unless needed.System Administrator

Checks: C-27883r2_chk

If the "dhclient" package is not installed, this is not applicable. Verify the DHCP client is configured to not send dynamic DNS updates. Procedure: # grep do-forward-updates /etc/dhclient.conf If the file is not present, does not contain this configuration, or has the setting set to "true", this is a finding.

Fix: F-24178r1_fix

Edit or add the "/etc/dhclient.conf" file and add or edit the "do-forward-updates" setting to false. Procedure: # echo "do-forward-updates false;" >> /etc/dhclient.conf

b

The system must ignore IPv6 ICMP redirect messages.

AC-4 - Medium - CCI-001551 - V-22550 - SV-37616r2_rule

RMF Control

AC-4

Severity

M

CCI

Version

GEN007860

Vuln IDs

V-22550

Rule IDs

SV-37616r2_rule

ICMP redirect messages are used by routers to inform hosts that a more direct route exists for a particular destination. These messages modify the host's route table and are unauthenticated. An illicit ICMP redirect message could result in a man-in-the-middle attack.System Administrator

Checks: C-36813r3_chk

Verify the system is configured to ignore IPv6 ICMP redirect messages. # cat /proc/sys/net/ipv6/conf/all/accept_redirects If the /proc/sys/net/ipv6/conf/all/accept_redirects entry does not exist because of compliance with GEN007720, this is not a finding. If the returned value is not "0", this is a finding.

Fix: F-31651r1_fix

Configure the system to ignore IPv6 ICMP redirect messages. Edit "/etc/sysctl.conf" and add a settings for "net.ipv6.conf.default.accept_redirects=0" and "net.ipv6.conf.all.accept_redirects=0". Restart the system for the setting to take effect.

b

The system must not forward IPv6 source-routed packets.

AC-4 - Medium - CCI-001551 - V-22553 - SV-37618r1_rule

RMF Control

AC-4

Severity

M

CCI

Version

GEN007920

Vuln IDs

V-22553

Rule IDs

SV-37618r1_rule

Source-routed packets allow the source of the packet to suggest that routers forward the packet along a different path than configured on the router, which can be used to bypass network security measures. This requirement applies only to the forwarding of source-routed traffic, such as when IPv6 forwarding is enabled and the system is functioning as a router. System AdministratorECSC-1

Checks: C-36815r1_chk

Determine if the system is configured to forward IPv6 source-routed packets. Procedure: # egrep "net.ipv6.conf.*forwarding" /etc/sysctl.conf If there are no entries found or the value of the entries is not = "0", this is a finding.

Fix: F-31656r1_fix

Configure the system to not forward IPv6 source-routed packets. Procedure: Edit the /etc/sysctl.conf file to include: net.ipv6.conf.all.forwarding = 0 net.ipv6.conf.default.forwarding = 0 Reload the kernel parameters: # sysctl -p

b

If the system is using LDAP for authentication or account information, the system must use a TLS connection using FIPS 140-2 approved cryptographic algorithms.

AC-17 - Medium - CCI-001453 - V-22555 - SV-37627r3_rule

RMF Control

AC-17

Severity

M

CCI

Version

GEN007980

Vuln IDs

V-22555

Rule IDs

SV-37627r3_rule

LDAP can be used to provide user authentication and account information, which are vital to system security. Communication between an LDAP server and a host using LDAP requires protection.System Administrator

Checks: C-36827r5_chk

To check to see if the system is an LDAP server, verify LDAP is running on the system: # ps -ef | grep ldap Find out which LDAP is used (if not determined via the command above). # rpm -qa | grep ldap If using nssldap: # grep base /etc/ldap.conf Check to see if the base is set to something besides the default of "dc=example,dc=com". If using openldap: # grep suffix /etc/openldap/slapd.conf Check whether the system is an LDAP client: # grep server /etc/ldap.conf # grep server /etc/openldap/ldap.conf Check whether the server option has an address other than the loopback, then check the nsswitch.conf file. # grep ldap /etc/nsswitch.conf Look for the following three lines: passwd: files ldap shadow: files ldap group: files ldap If all three files are not configured to look for an LDAP source, then the system is not using LDAP for authentication. If the system is not using LDAP for authentication, this is not applicable. Check if NSS LDAP is using TLS. # grep '^ssl start_tls' /etc/ldap.conf If no lines are returned, this is a finding. Check if NSS LDAP TLS is using only FIPS 140-2 approved cryptographic algorithms. # grep '^tls_ciphers' /etc/ldap.conf If the line is not present or contains ciphers not approved by FIPS 140-2, this is a finding. FIPS-approved ciphers include 3DES and AES. FIPS-approved hashes include the SHA hash family.

Fix: F-31665r1_fix

Edit "/etc/ldap.conf" and add a "ssl start_tls" and "tls_ciphers" options with only FIPS 140-2 approved ciphers.

b

If the system is using LDAP for authentication or account information, certificates used to authenticate to the LDAP server must be provided from DoD PKI or a DoD-approved external PKI.

IA-5 - Medium - CCI-000185 - V-22556 - SV-37631r1_rule

RMF Control

IA-5

Severity

M

CCI

CCI-000185

Version

GEN008000

Vuln IDs

V-22556

Rule IDs

SV-37631r1_rule

LDAP can be used to provide user authentication and account information, which are vital to system security. Communication between an LDAP server and a host using LDAP requires authentication.System AdministratorDCNR-1

Checks: C-36829r1_chk

Verify the source of the LDAP certificates Check if the system is using NSS LDAP. # grep -v '^#' /etc/nsswitch.conf | grep ldap If no lines are returned, this vulnerability is not applicable. Verify with the SA that the system is connected to the GIG. If the system part of a stand alone network which is not connected to the GIG this vulnerability is not applicable. Verify a certificate is used for client authentication to the server. # grep -i '^tls_cert' /etc/ldap.conf If no line is found, this is a finding. List the certificate issuer. # openssl x509 -text -in <cert> If the certificate is not issued by DoD PKI or a DoD-approved external PKI, this is a finding.

Fix: F-31668r1_fix

Edit "/etc/ldap.conf" and add or edit the 'tls_cert' setting to reference a file containing a client certificate issued by DoD PKI or a DoD-approved external PKI.

b

If the system is using LDAP for authentication or account information, the LDAP TLS connection must require the server provide a certificate with a valid trust path to a trusted CA.

IA-5 - Medium - CCI-000185 - V-22557 - SV-37632r1_rule

RMF Control

IA-5

Severity

M

CCI

CCI-000185

Version

GEN008020

Vuln IDs

V-22557

Rule IDs

SV-37632r1_rule

The NSS LDAP service provides user mappings which are a vital component of system security. Communication between an LDAP server and a host using LDAP for NSS require authentication.System AdministratorDCNR-1

Checks: C-36831r1_chk

Check if the system is using NSS LDAP. # grep -v '^#' /etc/nsswitch.conf | grep ldap If no lines are returned, this vulnerability is not applicable. Verify a server certificate is required and verified by the NSS LDAP configuration. # grep -i '^tls_checkpeer' /etc/ldap.conf If no line is returned, or the value is not "yes", this is a finding.

Fix: F-31669r1_fix

Edit "/etc/ldap.conf" and add or set the "tls_checkpeer" setting to "yes".

b

If the system is using LDAP for authentication or account information, the system must verify the LDAP server's certificate has not been revoked.

IA-5 - Medium - CCI-000185 - V-22558 - SV-37634r1_rule

RMF Control

IA-5

Severity

M

CCI

CCI-000185

Version

GEN008040

Vuln IDs

V-22558

Rule IDs

SV-37634r1_rule

LDAP can be used to provide user authentication and account information, which are vital to system security. Communication between an LDAP server and a host using LDAP requires authentication.System AdministratorDCNR-1

Checks: C-36834r1_chk

Check if the system is using NSS LDAP. # grep -v '^#' /etc/nsswitch.conf | grep ldap If no lines are returned, this vulnerability is not applicable. Verify the NSS LDAP client is configured to check certificates against a certificate revocation list. # grep -i '^tls_crlcheck' /etc/ldap.conf If the setting does not exist, or the value is not "all", this is a finding.

Fix: F-31672r1_fix

Edit "/etc/ldap.conf" and add or set the "tls_crlcheck" setting to "all".

b

If the system is using LDAP for authentication or account information the /etc/ldap.conf (or equivalent) file must have mode 0644 or less permissive.

AC-6 - Medium - CCI-000225 - V-22559 - SV-37951r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN008060

Vuln IDs

V-22559

Rule IDs

SV-37951r1_rule

LDAP can be used to provide user authentication and account information, which are vital to system security. The LDAP client configuration must be protected from unauthorized modification.System AdministratorECLP-1

Checks: C-37235r1_chk

Check the permissions of the file. # ls -lL /etc/ldap.conf If the mode of the file is more permissive than 0644, this is a finding.

Fix: F-32441r1_fix

Change the permissions of the file. # chmod 0644 /etc/ldap.conf

b

If the system is using LDAP for authentication or account information, the /etc/ldap.conf (or equivalent) file must be owned by root.

AC-6 - Medium - CCI-000225 - V-22560 - SV-37953r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN008080

Vuln IDs

V-22560

Rule IDs

SV-37953r1_rule

LDAP can be used to provide user authentication and account information, which are vital to system security. The LDAP client configuration must be protected from unauthorized modification.System AdministratorECLP-1

Checks: C-37239r1_chk

Check the ownership of the file. # ls -lL /etc/ldap.conf If the file is not owned by root, this is a finding.

Fix: F-32442r1_fix

Change the owner of the file. # chown root /etc/ldap.conf

b

If the system is using LDAP for authentication or account information, the /etc/ldap.conf (or equivalent) file must be group-owned by root, bin, sys, or system.

AC-6 - Medium - CCI-000225 - V-22561 - SV-37955r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN008100

Vuln IDs

V-22561

Rule IDs

SV-37955r1_rule

LDAP can be used to provide user authentication and account information, which are vital to system security. The LDAP client configuration must be protected from unauthorized modification.System AdministratorECLP-1

Checks: C-37244r1_chk

Check the group ownership of the file. Procedure: # ls -lL /etc/ldap.conf If the file is not group-owned by root, bin, sys, or system, this is a finding.

Fix: F-32444r1_fix

Change the group owner of the file to root, bin, sys, or system. Procedure: # chgrp root /etc/ldap.conf

b

If the system is using LDAP for authentication or account information, the /etc/ldap.conf (or equivalent) file must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22562 - SV-37956r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN008120

Vuln IDs

V-22562

Rule IDs

SV-37956r1_rule

LDAP can be used to provide user authentication and account information, which are vital to system security. The LDAP client configuration must be protected from unauthorized modification.System AdministratorECLP-1

Checks: C-37245r1_chk

Check the permissions of the file. # ls -lL /etc/ldap.conf If the mode includes a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-32445r1_fix

Remove the extended ACL from the "/etc/ldap.conf" file. # setfacl --remove-all /etc/ldap.conf

b

If the system is using LDAP for authentication or account information, the TLS certificate authority file and/or directory (as appropriate) must be owned by root.

AC-6 - Medium - CCI-000225 - V-22563 - SV-37959r3_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN008140

Vuln IDs

V-22563

Rule IDs

SV-37959r3_rule

LDAP can be used to provide user authentication and account information, which are vital to system security. The LDAP client configuration must be protected from unauthorized modification.System Administrator

Checks: C-37252r5_chk

Determine if LDAP is used for account information on the system. To check to see if the system is an LDAP server, verify LDAP is running on the system: # ps -ef | grep ldap Find out which LDAP is used (if not determined via the command above). # rpm -qa | grep ldap If using nssldap: # grep base /etc/ldap.conf Check to see if the base is set to something besides the default of "dc=example,dc=com". If using openldap: # grep suffix /etc/openldap/slapd.conf Check whether the system is an LDAP client: # grep server /etc/ldap.conf # grep server /etc/openldap/ldap.conf Check whether the server option has an address other than the loopback, then check the nsswitch.conf file. # grep ldap /etc/nsswitch.conf Look for the following three lines: passwd: files ldap shadow: files ldap group: files ldap If no un-commented reference to "ldap" is identified, LDAP is not used for account information on the system, and this is not applicable. Determine the certificate authority file and/or directory. # grep -i '^tls_cacert' /etc/ldap.conf For each file or directory returned, check the ownership. # ls -lLd <certpath> If the owner of any file or directory is not root, this is a finding.

Fix: F-32446r1_fix

Change the ownership of the file or directory. # chown root <certpath>

b

If the system is using LDAP for authentication or account information, the TLS certificate authority file and/or directory (as appropriate) must be group-owned by root, bin, sys, or system.

AC-6 - Medium - CCI-000225 - V-22564 - SV-37961r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN008160

Vuln IDs

V-22564

Rule IDs

SV-37961r1_rule

LDAP can be used to provide user authentication and account information, which are vital to system security. The LDAP client configuration must be protected from unauthorized modificationSystem AdministratorECLP-1

Checks: C-37260r1_chk

Determine the certificate authority file and/or directory. # grep -i '^tls_cacert' /etc/ldap.conf For each file or directory returned, check the group ownership. # ls -lLd <certpath> If the group-owner of any file or directory is not root, bin, sys, or system, this is a finding.

Fix: F-32447r1_fix

Change the group ownership of the file or directory. # chgrp root <certpath>

b

If the system is using LDAP for authentication or account information, the TLS certificate authority file and/or directory (as appropriate) must have mode 0644 (0755 for directories) or less permissive.

AC-6 - Medium - CCI-000225 - V-22565 - SV-37962r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN008180

Vuln IDs

V-22565

Rule IDs

SV-37962r1_rule

LDAP can be used to provide user authentication and account information, which are vital to system security. The LDAP client configuration must be protected from unauthorized modification.System AdministratorECLP-1

Checks: C-37261r1_chk

Determine the certificate authority file and/or directory. Procedure: # grep -i '^tls_cacert' /etc/ldap.conf For each file or directory returned, check the permissions. Procedure: # ls -lLd <certpath> If the mode of the file is more permissive than 0644 (or 0755 for directories), this is a finding.

Fix: F-32448r1_fix

Change the mode of the file or directory. File Procedure: # chmod 0644 <certpath> Directory Procedure: # chmod 0755 <certpath>

b

If the system is using LDAP for authentication or account information, the LDAP TLS certificate authority file and/or directory (as appropriate) must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22566 - SV-37964r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN008200

Vuln IDs

V-22566

Rule IDs

SV-37964r1_rule

LDAP can be used to provide user authentication and account information, which are vital to system security. The LDAP client configuration must be protected from unauthorized modification.System AdministratorECLP-1

Checks: C-37262r1_chk

Determine the certificate authority file and/or directory. # grep -i '^tls_cacert' /etc/ldap.conf For each file or directory returned, check the permissions. # ls -lLd <certpath> If the mode of the file or directory contains a '+', an extended ACL is present. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-32461r1_fix

Remove the extended ACL from the certificate file. Procedure: For each certificate file found remove all extended permissions # setfacl --remove-all <certpath>

b

For systems using NSS LDAP, the TLS certificate file must be owned by root.

AC-6 - Medium - CCI-000225 - V-22567 - SV-37965r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN008220

Vuln IDs

V-22567

Rule IDs

SV-37965r1_rule

The NSS LDAP service provides user mappings which are a vital component of system security. Its configuration must be protected from unauthorized modification.System AdministratorECLP-1

Checks: C-37263r1_chk

Determine the certificate file. # grep -i '^tls_cert' /etc/ldap.conf Check the ownership. # ls -lL <certpath> If the owner of the file is not root, this is a finding.

Fix: F-32470r1_fix

Change the ownership of the file. # chown root <certpath>

b

If the system is using LDAP for authentication or account information, the LDAP TLS certificate file must be group-owned by root, bin, sys, or system.

AC-6 - Medium - CCI-000225 - V-22568 - SV-37967r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN008240

Vuln IDs

V-22568

Rule IDs

SV-37967r1_rule

LDAP can be used to provide user authentication and account information, which are vital to system security. The LDAP client configuration must be protected from unauthorized modification.System AdministratorECLP-1

Checks: C-37265r1_chk

Determine the certificate file. Procedure: # grep -i '^tls_cert' /etc/ldap.conf Check the group ownership. Procedure: # ls -lL <certpath> If the group owner of the file is not root, bin, sys, or system, this is a finding.

Fix: F-32501r1_fix

Change the group ownership of the file. Procedure: # chgrp root <certpath>

b

If the system is using LDAP for authentication or account information, the LDAP TLS certificate file must have mode 0644 or less permissive.

AC-6 - Medium - CCI-000225 - V-22569 - SV-37966r2_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN008260

Vuln IDs

V-22569

Rule IDs

SV-37966r2_rule

LDAP can be used to provide user authentication and account information, which are vital to system security. The LDAP client configuration must be protected from unauthorized modification.System Administrator

Checks: C-37264r2_chk

Determine the certificate file. # grep -i '^tls_cert' /etc/ldap.conf Check the permissions. # ls -lL <certpath> If the mode of the file is more permissive than 0644, this is a finding.

Fix: F-32487r1_fix

Change the mode of the file. # chmod 0644 <certpath>

b

If the system is using LDAP for authentication or account information, the LDAP TLS certificate file must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22570 - SV-37968r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN008280

Vuln IDs

V-22570

Rule IDs

SV-37968r1_rule

LDAP can be used to provide user authentication and account information, which are vital to system security. The LDAP client configuration must be protected from unauthorized modification.System AdministratorECLP-1

Checks: C-37266r1_chk

Determine the certificate file. # grep -i '^tls_cert' /etc/ldap.conf Check the permissions. # ls -lL <certpath> If the mode of the file contains a '+', an extended ACL is present. This is a finding.

Fix: F-32502r1_fix

Remove the extended ACL from the certificate file. Procedure: For each certificate file found remove all extended permissions. # setfacl --remove-all <certpath>

b

If the system is using LDAP for authentication or account information, the LDAP TLS key file must be owned by root.

AC-6 - Medium - CCI-000225 - V-22571 - SV-37969r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN008300

Vuln IDs

V-22571

Rule IDs

SV-37969r1_rule

LDAP can be used to provide user authentication and account information, which are vital to system security. The LDAP client configuration must be protected from unauthorized modification.System AdministratorECLP-1

Checks: C-37267r1_chk

Determine the key file. # grep -i '^tls_key' /etc/ldap.conf Check the ownership. # ls -lL <keypath> If the owner of the file is not root, this is a finding.

Fix: F-32503r1_fix

Change the ownership of the file. # chown root <keypath>

b

If the system is using LDAP for authentication or account information, the LDAP TLS key file must be group-owned by root, bin, or sys.

AC-6 - Medium - CCI-000225 - V-22572 - SV-37971r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN008320

Vuln IDs

V-22572

Rule IDs

SV-37971r1_rule

LDAP can be used to provide user authentication and account information, which are vital to system security. The LDAP client configuration must be protected from unauthorized modification.System AdministratorECLP-1

Checks: C-37268r1_chk

Determine the key file. # grep -i '^tls_key' /etc/ldap.conf Check the group ownership. # ls -lL <keypath> If the file is not group owned by root, bin, or sys, this is a finding.

Fix: F-32505r1_fix

Change the group ownership of the file. # chgrp root <keypath>

b

If the system is using LDAP for authentication or account information, the LDAP TLS key file must have mode 0600 or less permissive.

AC-6 - Medium - CCI-000225 - V-22573 - SV-37973r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN008340

Vuln IDs

V-22573

Rule IDs

SV-37973r1_rule

LDAP can be used to provide user authentication and account information, which are vital to system security. The LDAP client configuration must be protected from unauthorized modification. Note: Depending on the particular implementation, group and other read permission may be necessary for unprivileged users to successfully resolve account information using LDAP. This will still be a finding, as these permissions provide users with access to system authenticators.System AdministratorECLP-1

Checks: C-37269r1_chk

Determine the key file. # grep -i '^tls_key' /etc/ldap.conf Check the permissions. # ls -lL <keypath> If the mode of the file is more permissive than 0600, this is a finding.

Fix: F-32506r1_fix

Change the mode of the file. # chmod 0600 <keypath>

b

If the system is using LDAP for authentication or account information, the LDAP TLS key file must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22574 - SV-37977r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN008360

Vuln IDs

V-22574

Rule IDs

SV-37977r1_rule

LDAP can be used to provide user authentication and account information, which are vital to system security. The LDAP client configuration must be protected from unauthorized modification.System AdministratorECLP-1

Checks: C-37272r3_chk

Determine the key file. # grep -i '^tls_key' /etc/ldap.conf Check the permissions. # ls -lL <keypath> If the permissions of the file contains a '+', an extended ACL is present. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-32509r1_fix

Remove the extended ACL from the key file. Procedure: For each key file found remove all extended permissions. # setfacl --remove-all <keypath>

a

The system must use available memory address randomization techniques.

CM-6 - Low - CCI-000366 - V-22576 - SV-37979r1_rule

RMF Control

CM-6

Severity

L

CCI

Version

GEN008420

Vuln IDs

V-22576

Rule IDs

SV-37979r1_rule

Successful exploitation of buffer overflow vulnerabilities relies in some measure to having a predictable address structure of the executing program. Address randomization techniques reduce the probability of a successful exploit.System AdministratorECSC-1

Checks: C-37277r1_chk

Verify exec-shield is enabled if present. # cat /proc/sys/kernel/exec-shield If the file is present and contains a value of "0", this is a finding.

Fix: F-32513r1_fix

Edit the kernel boot parameters, or "/etc/sysctl.conf", and set exec-shield to "1". Reboot the system.

a

Automated file system mounting tools must not be enabled unless needed.

CM-6 - Low - CCI-000366 - V-22577 - SV-37980r2_rule

RMF Control

CM-6

Severity

L

CCI

Version

GEN008440

Vuln IDs

V-22577

Rule IDs

SV-37980r2_rule

Automated file system mounting tools may provide unprivileged users with the ability to access local media and network shares. If this access is not necessary for the system's operation, it must be disabled to reduce the risk of unauthorized access to these resources.System Administrator

Checks: C-37278r1_chk

If the autofs service is needed, this vulnerability is not applicable. Check if the autofs service is running. # service autofs status If the service is running, this is a finding.

Fix: F-32515r1_fix

Stop and disable the autofs service. # service autofs stop # chkconfig autofs off

a

The system must have USB disabled unless needed.

CM-6 - Low - CCI-000366 - V-22578 - SV-37981r1_rule

RMF Control

CM-6

Severity

L

CCI

Version

GEN008460

Vuln IDs

V-22578

Rule IDs

SV-37981r1_rule

USB is a common computer peripheral interface. USB devices may include storage devices with the potential to install malicious software on a system or exfiltrate data.trueSystem AdministratorECSC-1

Checks: C-37280r1_chk

If the system needs USB, this vulnerability is not applicable. Check if the directory "/proc/bus/usb" exists. If so, this is a finding.

Fix: F-32517r1_fix

Edit the grub bootloader file "/boot/grub/grub.conf" or "/boot/grub/menu.lst" by appending the "nousb" parameter to the kernel boot line.

a

The system must have USB Mass Storage disabled unless needed.

CM-6 - Low - CCI-000366 - V-22579 - SV-37982r1_rule

RMF Control

CM-6

Severity

L

CCI

Version

GEN008480

Vuln IDs

V-22579

Rule IDs

SV-37982r1_rule

USB is a common computer peripheral interface. USB devices may include storage devices with the potential to install malicious software on a system or exfiltrate datatrueSystem AdministratorECSC-1

Checks: C-37282r1_chk

If the system needs USB storage, this vulnerability is not applicable. Check if usb-storage is prevented from loading. # grep 'install usb-storage /bin/true' /etc/modprobe.conf /etc/modprobe.d/* If no results are returned, this is a finding.

Fix: F-32519r1_fix

Prevent the usb-storage module from loading. # echo 'install usb-storage /bin/true' >> /etc/modprobe.conf

a

The system must have IEEE 1394 (Firewire) disabled unless needed.

CM-6 - Low - CCI-000366 - V-22580 - SV-37983r1_rule

RMF Control

CM-6

Severity

L

CCI

Version

GEN008500

Vuln IDs

V-22580

Rule IDs

SV-37983r1_rule

Firewire is a common computer peripheral interface. Firewire devices may include storage devices with the potential to install malicious software on a system or exfiltrate data.trueSystem AdministratorECSC-1

Checks: C-37283r1_chk

If the system needs IEEE 1394 (Firewire), this is not applicable. Check if the firewire module is not disabled. # grep 'install ieee1394 /bin/true' /etc/modprobe.conf /etc/modprobe.d/* If no results are returned, this is a finding.

Fix: F-32520r1_fix

Prevent the system from loading the firewire module. # echo 'install ieee1394 /bin/true' >> /etc/modprobe.conf

b

The system must employ a local firewall.

SC-7 - Medium - CCI-001118 - V-22582 - SV-37984r1_rule

RMF Control

SC-7

Severity

M

CCI

CCI-001118

Version

GEN008520

Vuln IDs

V-22582

Rule IDs

SV-37984r1_rule

A local firewall protects the system from exposing unnecessary or undocumented network services to the local enclave. If a system within the enclave is compromised, firewall protection on an individual system continues to protect it from attack.System AdministratorECSC-1

Checks: C-37285r1_chk

Determine if the system is using a local firewall. # chkconfig --list iptables If the service is not "on" in the standard runlevel (ordinarily 3 or 5), this is a finding.

Fix: F-32522r1_fix

Enable the system's local firewall. # chkconfig iptables on # service iptables start

b

The system's local firewall must implement a deny-all, allow-by-exception policy.

SC-7 - Medium - CCI-001109 - V-22583 - SV-37985r1_rule

RMF Control

SC-7

Severity

M

CCI

CCI-001109

Version

GEN008540

Vuln IDs

V-22583

Rule IDs

SV-37985r1_rule

A local firewall protects the system from exposing unnecessary or undocumented network services to the local enclave. If a system within the enclave is compromised, firewall protection on an individual system continues to protect it from attack.System AdministratorECSC-1

Checks: C-37287r3_chk

Check the firewall rules for a default deny rule. # iptables --list Example of a rule meeting this criteria: REJECT all -- anywhere anywhere reject-with icmp-host-prohibited A rule using DROP is also acceptable. The default rule should be the last rule of a table and match all traffic. If there is no default deny rule, this is a finding.

Fix: F-32525r2_fix

Edit "/etc/sysconfig/iptables" and add a default deny rule. An example of a default deny rule: -A RH-Firewall-1-INPUT -j REJECT --reject-with icmp-host-prohibited Restart the iptable service. # service iptables restart

a

The system must use a Linux Security Module configured to limit the privileges of system services.

CM-6 - Low - CCI-000366 - V-22584 - SV-26978r1_rule

RMF Control

CM-6

Severity

L

CCI

Version

GEN000000-LNX00800

Vuln IDs

V-22584

Rule IDs

SV-26978r1_rule

Linux Security Modules such as SELinux and AppArmor can be used to provide protection from software exploits by explicitly defining the privileges permitted to each software package.System Administrator

Checks: C-36036r1_chk

Check if SELinux is enabled with at least a "targeted" policy. # grep ^SELINUX /etc/sysconfig/selinux If the SELINUX option is not set to "enforcing", this is a finding. If the SELINUXTYPE option is not set to "targeted" or "strict", this is a finding. If the use of the system is incompatible with the confines of SELinux this rule may be waived.

Fix: F-31279r2_fix

Enable one of the SELinux policies. Edit /etc/sysconfig/selinux and set the value of the SELINUX option to "enforcing" and SELINUXTYPE to "targeted" or "strict". Restart the system.

b

The system's boot loader configuration file(s) must not have extended ACLs.

AC-6 - Medium - CCI-000225 - V-22585 - SV-26984r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN008740

Vuln IDs

V-22585

Rule IDs

SV-26984r1_rule

File system extended ACLs provide access to files beyond what is allowed by the mode numbers of the files. If extended ACLs are present on the system's boot loader configuration file(s), these files may be vulnerable to unauthorized access or modification, which could compromise the system's boot process.System AdministratorECLP-1

Checks: C-37229r3_chk

Check the permissions of the file. # ls -lL /boot/grub/grub.conf If the permissions of the file or directory contains a '+', an extended ACL is present. This is a finding.

Fix: F-24248r1_fix

Remove the extended ACL from the file. # setfacl --remove-all /etc/grub.conf

b

The system's boot loader configuration files must be owned by root.

AC-6 - Medium - CCI-000225 - V-22586 - SV-26986r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN008760

Vuln IDs

V-22586

Rule IDs

SV-26986r1_rule

The system's boot loader configuration files are critical to the integrity of the system and must be protected. Unauthorized modification of these files resulting from improper ownership could compromise the system's boot loader configuration.System AdministratorECLP-1

Checks: C-37231r1_chk

Check the ownership of the file. # ls -lLd /boot/grub/grub.conf If the owner of the file is not root, this is a finding.

Fix: F-32438r1_fix

Change the ownership of the file. # chown root /boot/grub/grub.conf

b

The system's boot loader configuration file(s) must be group-owned by root, bin, sys, or system.

AC-6 - Medium - CCI-000225 - V-22587 - SV-26988r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN008780

Vuln IDs

V-22587

Rule IDs

SV-26988r1_rule

The system's boot loader configuration files are critical to the integrity of the system and must be protected. Unauthorized modifications resulting from improper group ownership may compromise the boot loader configuration.System AdministratorECLP-1

Checks: C-37240r1_chk

Check the group ownership of the file. # ls -lLd /boot/grub/grub.conf If the group-owner of the file is not root, bin, sys, or system this is a finding.

Fix: F-32443r1_fix

Change the group ownership of the file. # chgrp root /boot/grub/grub.conf

a

The system package management tool must cryptographically verify the authenticity of software packages during installation.

CM-5 - Low - CCI-000351 - V-22588 - SV-26990r2_rule

RMF Control

CM-5

Severity

L

CCI

CCI-000351

Version

GEN008800

Vuln IDs

V-22588

Rule IDs

SV-26990r2_rule

To prevent the installation of software from unauthorized sources, the system package management tool must use cryptographic algorithms to verify the packages are authentic.System Administrator

Checks: C-27933r3_chk

Verify YUM signature validation is not disabled. # grep gpgcheck /etc/yum.conf /etc/yum.repos.d/* If no results are returned, or the returned “gpgcheck” settings are not equal to “1”, this is a finding.

Fix: F-24256r2_fix

Edit the YUM configuration containing "gpgcheck=0" and set the value to "1".

a

The system package management tool must not automatically obtain updates.

SI-2 - Low - CCI-001233 - V-22589 - SV-26992r1_rule

RMF Control

SI-2

Severity

L

CCI

CCI-001233

Version

GEN008820

Vuln IDs

V-22589

Rule IDs

SV-26992r1_rule

System package management tools can obtain a list of updates and patches from a package repository and make this information available to the SA for review and action. Using a package repository outside of the organization's control presents a risk of malicious packages being introduced.System AdministratorECSC-1

Checks: C-27935r1_chk

Verify the YUM service is enabled. # service yum-updatesd status If the service is enabled, this is a finding.

Fix: F-24258r1_fix

Disable the yum service. # chkconfig yum-updatesd off ; service yum-updatesd stop

b

The access.conf file must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22595 - SV-26998r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN000000-LNX00450

Vuln IDs

V-22595

Rule IDs

SV-26998r1_rule

If the access permissions are more permissive than 0640, system security could be compromised.System AdministratorECLP-1

Checks: C-35941r3_chk

Check the permissions of the file. # ls -lL /etc/security/access.conf If the permissions of the file or directory contain a '+', an extended ACL is present. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-24264r1_fix

Remove the extended ACL from the file. # setfacl --remove-all /etc/security/access.conf

b

The /etc/sysctl.conf file must not have an extended ACL.

AC-6 - Medium - CCI-000225 - V-22596 - SV-26999r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN000000-LNX00530

Vuln IDs

V-22596

Rule IDs

SV-26999r1_rule

The sysctl.conf file specifies the values for kernel parameters to be set on boot. These settings can affect the system's security.System AdministratorECLP-1

Checks: C-35992r3_chk

Check the permissions of the file. # ls -lL /etc/sysctl.conf If the permissions of the file or directory contain a '+', an extended ACL is present. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix: F-24265r1_fix

Remove the extended ACL from the file. # setfacl --remove-all /etc/sysctl.conf

a

Auditing must be enabled at boot by setting a kernel parameter.

CM-6 - Low - CCI-000366 - V-22598 - SV-27001r1_rule

RMF Control

CM-6

Severity

L

CCI

Version

GEN000000-LNX00720

Vuln IDs

V-22598

Rule IDs

SV-27001r1_rule

If auditing is enabled late in the boot process, the actions of startup scripts may not be audited. Some audit systems also maintain state information only available if auditing is enabled before a given process is created.System Administrator

Checks: C-36032r1_chk

Check for the audit=1 kernel parameter. # grep 'audit=1' /proc/cmdline If no results are returned, this is a finding.

Fix: F-31278r1_fix

Edit the grub bootloader file /boot/grub/grub.conf or /boot/grub/menu.lst by appending the "audit=1" parameter to the kernel boot line. Reboot the system for the change to take effect.

b

The system must not be running any routing protocol daemons, unless the system is a router.

CM-6 - Medium - CCI-000366 - V-22665 - SV-37926r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN005590

Vuln IDs

V-22665

Rule IDs

SV-37926r1_rule

Routing protocol daemons are typically used on routers to exchange network topology information with other routers. If this software is used when not required, system network information may be unnecessarily transmitted across the network.System AdministratorECSC-1

Checks: C-37168r3_chk

Check for any running routing protocol daemons. If the system is a VM host and acts as a router solely for the benefits of its client systems, then this rule is not applicable. # chkconfig --list |grep :on|egrep '(ospf|route|bgp|zebra|quagga)' If any routing protocol daemons are listed, this is a finding.

Fix: F-32420r1_fix

Disable any routing protocol daemons.

b

System audit logs must be group-owned by root, bin, sys, or system.

AU-9 - Medium - CCI-000162 - V-22702 - SV-37914r1_rule

RMF Control

AU-9

Severity

M

CCI

CCI-000162

Version

GEN002690

Vuln IDs

V-22702

Rule IDs

SV-37914r1_rule

Sensitive system and user information could provide a malicious user with enough information to penetrate further into the system.System AdministratorECLP-1, ECTP-1

Checks: C-37140r1_chk

Check the group ownership of the audit logs. Procedure: # grep "^log_file" /etc/audit/auditd.conf|sed s/^[^\/]*//|xargs stat -c %G:%n If any audit log file is not group-owned by root, bin, sys, or system, this is a finding.

Fix: F-24520r1_fix

Change the group ownership of the audit log file(s). Procedure: # chgrp root <audit log file>

b

The FTPS/FTP service on the system must be configured with the Department of Defense (DoD) login banner.

AC-8 - Medium - CCI-000048 - V-23732 - SV-28606r1_rule

RMF Control

AC-8

Severity

M

CCI

Version

GEN000410

Vuln IDs

V-23732

Rule IDs

SV-28606r1_rule

Failure to display the logon banner prior to a logon attempt will negate legal proceedings resulting from unauthorized access to system resources. Note: SFTP and FTPS are encrypted alternatives to FTP to be used in place of FTP. SFTP is implemented by the SSH service and uses its banner configuration.System AdministratorECWM-1

Checks: C-35878r1_chk

FTP to the system. # ftp localhost Check for either of the following login banners based on the character limitations imposed by the system. An exact match is required. If one of these banners is not displayed, this is a finding. If the system does not run the FTP service, this is not applicable. DoD Login Banners: You are accessing a U.S. Government (USG) Information System (IS) that is provided for USG-authorized use only. By using this IS (which includes any device attached to this IS), you consent to the following conditions: -The USG routinely intercepts and monitors communications on this IS for purposes including, but not limited to, penetration testing, COMSEC monitoring, network operations and defense, personnel misconduct (PM), law enforcement (LE), and counterintelligence (CI) investigations. -At any time, the USG may inspect and seize data stored on this IS. -Communications using, or data stored on, this IS are not private, are subject to routine monitoring, interception, and search, and may be disclosed or used for any USG-authorized purpose. -This IS includes security measures (e.g., authentication and access controls) to protect USG interests--not for your personal benefit or privacy. -Notwithstanding the above, using this IS does not constitute consent to PM, LE or CI investigative searching or monitoring of the content of privileged communications, or work product, related to personal representation or services by attorneys, psychotherapists, or clergy, and their assistants. Such communications and work product are private and confidential. See User Agreement for details. OR I've read & consent to terms in IS user agreem't.

Fix: F-25878r2_fix

Provide the proper text for the DoD banner to be presented by the FTP server to the user. For vsftp: Examine the /etc/vsftp.conf file for the "banner_file" entry. (i.e. banner_file = /etc/banner/vsftp) For gssftp: Examine the /etc/xinetd.d/gssftp file for the "banner" entry. (i.e. banner = /etc/banner/gssftp) For both: Add the banner entry if one is not found. Modify or create the referenced banner file to contain one of the following DoD login banners (based on the character limitations imposed by the system). DoD Login Banners: You are accessing a U.S. Government (USG) Information System (IS) that is provided for USG-authorized use only. By using this IS (which includes any device attached to this IS), you consent to the following conditions: -The USG routinely intercepts and monitors communications on this IS for purposes including, but not limited to, penetration testing, COMSEC monitoring, network operations and defense, personnel misconduct (PM), law enforcement (LE), and counterintelligence (CI) investigations. -At any time, the USG may inspect and seize data stored on this IS. -Communications using, or data stored on, this IS are not private, are subject to routine monitoring, interception, and search, and may be disclosed or used for any USG-authorized purpose. -This IS includes security measures (e.g., authentication and access controls) to protect USG interests--not for your personal benefit or privacy. -Notwithstanding the above, using this IS does not constitute consent to PM, LE or CI investigative searching or monitoring of the content of privileged communications, or work product, related to personal representation or services by attorneys, psychotherapists, or clergy, and their assistants. Such communications and work product are private and confidential. See User Agreement for details. OR I've read & consent to terms in IS user agreem't.

a

The system must use a separate file system for /var.

SC-32 - Low - CCI-001208 - V-23736 - SV-37641r1_rule

RMF Control

SC-32

Severity

L

CCI

Version

GEN003621

Vuln IDs

V-23736

Rule IDs

SV-37641r1_rule

The use of separate file systems for different paths can protect the system from failures resulting from a file system becoming full or failing.System AdministratorECSC-1

Checks: C-36839r1_chk

Determine if the /var path is a separate filesystem. # grep /var /etc/fstab If no result is returned, /var is not on a separate filesystem this is a finding.

Fix: F-31676r1_fix

Migrate the /var path onto a separate file system.

a

The system must use a separate file system for the system audit data path.

SC-32 - Low - CCI-001208 - V-23738 - SV-37642r1_rule

RMF Control

SC-32

Severity

L

CCI

Version

GEN003623

Vuln IDs

V-23738

Rule IDs

SV-37642r1_rule

The use of separate file systems for different paths can protect the system from failures resulting from a file system becoming full or failing.System AdministratorECSC-1

Checks: C-36840r1_chk

Determine if the /var/log/audit path is a separate filesystem. # grep /var/log/audit /etc/fstab If no result is returned, /var/log/audit is not on a separate filesystem this is a finding.

Fix: F-31677r1_fix

Migrate the /var/log/audit path onto a separate filesystem.

a

The system must use a separate file system for /tmp (or equivalent).

SC-32 - Low - CCI-001208 - V-23739 - SV-37395r1_rule

RMF Control

SC-32

Severity

L

CCI

Version

GEN003624

Vuln IDs

V-23739

Rule IDs

SV-37395r1_rule

The use of separate file systems for different paths can protect the system from failures resulting from a file system becoming full or failing.System AdministratorECSC-1

Checks: C-36078r1_chk

Determine if the /tmp path is a separate filesystem. # egrep "[\t ]/tmp[\t ]" /etc/fstab If no result is returned, /tmp is not on a separate filesystem this is a finding.

Fix: F-31325r1_fix

Migrate the /tmp path onto a separate file system.

b

TCP backlog queue sizes must be set appropriately.

Medium - V-23741 - SV-37594r1_rule

RMF Control

Severity

M

CCI

Version

GEN003601

Vuln IDs

V-23741

Rule IDs

SV-37594r1_rule

To provide some mitigation to TCP Denial of Service attacks, the TCP backlog queue sizes must be set to at least 1280 or in accordance with product-specific guidelines.System AdministratorECSC-1

Checks: C-36673r1_chk

# cat /proc/sys/net/ipv4/tcp_max_syn_backlog If the result is not 1280 or greater, this is a finding.

Fix: F-31631r1_fix

Edit /etc/sysctl.conf and add a setting for "net.ipv4.tcp_max_syn_backlog=1280". Procedure: # sysctl -p

b

Mail relaying must be restricted.

SI-8 - Medium - CCI-001305 - V-23952 - SV-37514r2_rule

RMF Control

SI-8

Severity

M

CCI

CCI-001305

Version

GEN004710

Vuln IDs

V-23952

Rule IDs

SV-37514r2_rule

If unrestricted mail relaying is permitted, unauthorized senders could use this host as a mail relay for the purpose of sending SPAM or other unauthorized activity.System Administrator

Checks: C-36173r2_chk

If the system uses sendmail examine the configuration files. Determine if sendmail only binds to loopback addresses by examining the "DaemonPortOptions" configuration options. Procedure: # grep -i "O DaemonPortOptions" /etc/mail/sendmail.cf If there are uncommented DaemonPortOptions lines, and all such lines specify system loopback addresses, this is not a finding. Otherwise, determine if sendmail is configured to allow open relay operation. Procedure: # grep -i promiscuous_relay /etc/mail/sendmail.mc If the promiscuous relay feature is enabled, this is a finding. If the system uses Postfix, locate the main.cf file. Procedure: # find / -name main.cf Determine if Postfix only binds to loopback addresses by examining the "inet_interfaces" line. Procedure: # grep inet_interfaces </path/to/main.cf> If "inet_interfaces" is set to "loopback-only" or contains only loopback addresses such as 127.0.0.1 and [::1], Postfix is not listening on external network interfaces, and this is not a finding. Otherwise, determine if Postfix is configured to restrict clients permitted to relay mail by examining the "smtpd_client_restrictions" line. Procedure: # grep smtpd_client_restrictions </path/to/main.cf> If the "smtpd_client_restrictions" line is missing, or does not contain "reject", this is a finding. If the line contains "permit" before "reject", this is a finding. If the system is using other SMTP software, consult the software's documentation for procedures to verify mail relaying is restricted.

Fix: F-31424r2_fix

If the system uses sendmail, edit the sendmail.mc file and remove the "promiscuous_relay" configuration. Rebuild the sendmail.cf file from the modified sendmail.mc and restart the service. If the system does not need to receive mail from external hosts, add one or more DaemonPortOptions lines referencing system loopback addresses (such as "O DaemonPortOptions=Addr=127.0.0.1,Port=smtp,Name=MTA") and remove lines containing non-loopback addresses. Restart the service. If the system uses Postfix, edit the main.cf file and add or edit the "smtpd_client_restrictions" line to have contents "permit_mynetworks, reject" or a similarly restrictive rule. If the system does not need to receive mail from external hosts, add or edit the "inet_interfaces" line to have contents "loopback-only" or a set of loopback addresses for the system. Restart the service. If the system is using other SMTP software, consult the software's documentation for procedures to restrict mail relaying.

b

The 'ldd' command must be disabled unless it protects against the execution of untrusted files.

CM-2 - Medium - CCI-000305 - V-23953 - SV-37621r2_rule

RMF Control

CM-2

Severity

M

CCI

Version

GEN007960

Vuln IDs

V-23953

Rule IDs

SV-37621r2_rule

The 'ldd' command provides a list of dependent libraries needed by a given binary, which is useful for troubleshooting software. Instead of parsing the binary file, some 'ldd' implementations invoke the program with a special environment variable set, which causes the system dynamic linker to display the list of libraries. Specially crafted binaries can specify an alternate dynamic linker which may cause a program to be executed instead of examined. If the program is from an untrusted source, such as in a user home directory, or a file suspected of involvement in a system compromise, unauthorized software may be executed with the rights of the user running 'ldd'. Some 'ldd' implementations include protections that prevent the execution of untrusted files. Recent RHEL 5 glibc RPMs also protect against the execution of untrusted files. If such protections exist, this requirement is not applicable. An acceptable method of disabling 'ldd' is changing its mode to 0000. The SA may conduct troubleshooting by temporarily changing the mode to allow execution and running the 'ldd' command as an unprivileged user upon trusted system binaries.System Administrator

Checks: C-36820r3_chk

Check the system for the 'ldd' binary. Procedure: # ls -lL /usr/bin/ldd If the 'ldd' binary has any executable permissions bits set, this is a finding.

Fix: F-31658r1_fix

Remove the execute permissions from the 'ldd' executable. Procedure: # chmod a-x /usr/bin/ldd

b

The system must not respond to ICMPv6 echo requests sent to a broadcast address.

CM-6 - Medium - CCI-000366 - V-23972 - SV-29788r1_rule

RMF Control

CM-6

Severity

M

CCI

Version

GEN007950

Vuln IDs

V-23972

Rule IDs

SV-29788r1_rule

Responding to broadcast ICMP echo requests facilitates network mapping and provides a vector for amplification attacks.System AdministratorECSC-1

Checks: C-30069r1_chk

Check for an iptables rule that drops inbound IPv6 ICMP ECHO_REQUESTs sent to the all-hosts multicast address. Procedure: # less /etc/sysconfig/ip6tables Check for a rule in, or referenced by, the INPUT chain such as: -A INPUT -p icmpv6 -d ff02::1 --icmpv6-type 128 -j DROP If such a rule does not exist, this is a finding.

Fix: F-26899r1_fix

Add an iptables rule that drops inbound IPv6 ICMP ECHO_REQUESTs sent to the all-hosts multicast address. Edit /etc/sysconfig/ip6tables and add a rule in, or referenced by, the INPUT chain such as: -A INPUT -p icmpv6 -d ff02::1 --icmpv6-type 128 -j DROP Reload the iptables rules. Procedure: # service ip6tables restart

b

The Department of Defense (DoD) login banner must be displayed immediately prior to, or as part of, graphical desktop environment login prompts.

AC-8 - Medium - CCI-000048 - V-24331 - SV-37171r1_rule

RMF Control

AC-8

Severity

M

CCI

Version

GEN000402

Vuln IDs

V-24331

Rule IDs

SV-37171r1_rule

Failure to display the logon banner prior to a logon attempt will negate legal proceedings resulting from unauthorized access to system resources. This requirement applies to graphical desktop environments provided by the system to locally attached displays and input devices as well as to graphical desktop environments provided to remote systems, including thin clients.System AdministratorECWM-1

Checks: C-35876r1_chk

Access the graphical desktop environment(s) provided by the system and attempt to log in. Check for either of the following login banners based on the character limitations imposed by the system. An exact match is required. If one of these banners is not displayed, this is a finding. You are accessing a U.S. Government (USG) Information System (IS) that is provided for USG-authorized use only. By using this IS (which includes any device attached to this IS), you consent to the following conditions: -The USG routinely intercepts and monitors communications on this IS for purposes including, but not limited to, penetration testing, COMSEC monitoring, network operations and defense, personnel misconduct (PM), law enforcement (LE), and counterintelligence (CI) investigations. -At any time, the USG may inspect and seize data stored on this IS. -Communications using, or data stored on, this IS are not private, are subject to routine monitoring, interception, and search, and may be disclosed or used for any USG-authorized purpose. -This IS includes security measures (e.g., authentication and access controls) to protect USG interests- -not for your personal benefit or privacy. -Notwithstanding the above, using this IS does not constitute consent to PM, LE or CI investigative searching or monitoring of the content of privileged communications, or work product, related to personal representation or services by attorneys, psychotherapists, or clergy, and their assistants. Such communications and work product are private and confidential. See User Agreement for details. OR I've read & consent to terms in IS user agreem't.

Fix: F-31131r1_fix

Configure the system to display one of the DoD login banners prior to, or as part of, the graphical desktop environment login process. Procedure: Modify /usr/share/gdm/themes/RHEL/RHEL.xml by adding the following xml after the first two "pixmap" entries. <item type="rect" id="custom-dod-banner"> <pos anchor="nw" x="20%" y="10" width="80%" height="100%"/> <box> <item type="label"> <normal font="Sans Bold 9" color="#ffffff"/> <text> Insert the "approved text" here based on the character limitations imposed by the system. </text> </item> </box> </item> Approved text: DoD Login Banners: You are accessing a U.S. Government (USG) Information System (IS) that is provided for USG-authorized use only. By using this IS (which includes any device attached to this IS), you consent to the following conditions: -The USG routinely intercepts and monitors communications on this IS for purposes including, but not limited to, penetration testing, COMSEC monitoring, network operations and defense, personnel misconduct (PM), law enforcement (LE), and counterintelligence (CI) investigations. -At any time, the USG may inspect and seize data stored on this IS. -Communications using, or data stored on, this IS are not private, are subject to routine monitoring, interception, and search, and may be disclosed or used for any USG-authorized purpose. -This IS includes security measures (e.g., authentication and access controls) to protect USG interests--not for your personal benefit or privacy. -Notwithstanding the above, using this IS does not constitute consent to PM, LE or CI investigative searching or monitoring of the content of privileged communications, or work product, related to personal representation or services by attorneys, psychotherapists, or clergy, and their assistants. Such communications and work product are private and confidential. See User Agreement for details. OR I've read & consent to terms in IS user agreem't.

b

The system, if capable, must be configured to require the use of a CAC, PIV compliant hardware token, or Alternate Logon Token (ALT) for authentication.

IA-2 - Medium - CCI-000768 - V-24347 - SV-30004r2_rule

RMF Control

IA-2

Severity

M

CCI

CCI-000768

Version

GEN009120

Vuln IDs

V-24347

Rule IDs

SV-30004r2_rule

In accordance with CTO 07-015 PKI authentication is required. This provides stronger, two-factor authentication than using a username/password. NOTE: The following are exempt from this, however, they must meet all password requirements and must be documented with the IAO: - Stand-alone systems. - Application Accounts. - Students or unpaid employees (such as, interns) who are not eligible to receive or not in receipt of a CAC, PIV, or ALT. - Warfighters and support personnel located at operational tactical locations conducting wartime operations that are not collocated with RAPIDS workstations to issue CAC; are not eligible for CAC or do not have the capability to use ALT. - Test systems that have an Interim Approval to Test (IATT) and provide protection via separate VPN, firewall, or security measures preventing access to network and system components from outside the protection boundary documented in the IATT.System Administrator

Checks: C-30833r1_chk

Consult vendor documentation to determine if the system is capable of CAC authentication. If it is not, this is not applicable. Interview the SA to determine if all accounts not exempted by policy are using CAC authentication. If non-exempt accounts are not using CAC authentication, this is a finding.

Fix: F-27447r1_fix

Consult vendor documentation to determine the procedures necessary for configuring CAC authentication. Configure all accounts required by policy to use CAC authentication.

a

The system must be configured to send audit/system records to a remote audit server.

AU-3 - Low - CCI-000136 - V-24357 - SV-37948r4_rule

RMF Control

AU-3

Severity

L

CCI

CCI-000136

Version

GEN002870

Vuln IDs

V-24357

Rule IDs

SV-37948r4_rule

System/Audit records contain evidence that can be used in the investigation of compromised systems. To prevent this evidence from compromise, it must be sent to a separate system continuously. Methods for sending audit records include, but are not limited to, system audit tools used to send logs directly to another host or through the system's syslog service to another host.System Administrator

Checks: C-37233r6_chk

Verify the system is configured to forward all audit records to a remote server. If the system is not configured to provide this function, this is a finding. Procedure: Ensure the audit option for the kernel is enabled. # grep "audit" /boot/grub/grub.conf | grep -v "^#" If the kernel does not have the "audit=1" option specified, this is a finding. Ensure the kernel auditing is active. # grep "active" /etc/audisp/plugins.d/syslog.conf | grep -v "^#" If the "active" setting is either missing or not set to "yes", this is a finding. Ensure all audit records are forwarded to a remote server. # grep "\*.\*" /etc/syslog.conf |grep "@" | grep -v "^#" (for syslog) or: # grep "\*.\*" /etc/rsyslog.conf | grep "@" | grep -v "^#" (for rsyslog) If neither of these lines exist, it is a finding.

Fix: F-32440r3_fix

Configure the system to send audit records to a remote server. Procedure: These instructions assume a known remote audit server is available to this system. Modify /etc/syslog.conf or /etc/rsyslog.conf to contain a line sending all audit records to a remote audit server. The server is specified by placing an "@" before the DNS name or IP address in the line. *.* @<remote audit server> Edit the "active" line in /etc/audisp/plugins.d/syslog.conf so it shows "active = yes". Restart audit and syslog: # service auditd restart # service syslog restart Or: # service rsyslog restart

b

If the system is using LDAP for authentication or account information, the /etc/ldap.conf file (or equivalent) must not contain passwords.

IA-5 - Medium - CCI-000196 - V-24384 - SV-37643r3_rule

RMF Control

IA-5

Severity

M

CCI

CCI-000196

Version

GEN008050

Vuln IDs

V-24384

Rule IDs

SV-37643r3_rule

The authentication of automated LDAP connections between systems must not use passwords since more secure methods are available, such as PKI and Kerberos. Additionally, the storage of unencrypted passwords on the system is not permitted.System Administrator

Checks: C-36837r4_chk

Verify LDAP is running on the system. To check to see if the system is an LDAP server, run: # ps -ef | grep ldap Find out which LDAP is used (if not determined via the command above). # rpm -qa | grep ldap If using nssldap: # grep base /etc/ldap.conf Check to see if the base is set to something besides the default of "dc=example,dc=com". If using openldap: # grep suffix /etc/openldap/slapd.conf Check whether the system is an LDAP client: # grep server /etc/ldap.conf # grep server /etc/openldap/ldap.conf Check whether the server option has an address other than the loopback, then check the nsswitch.conf file: # grep ldap /etc/nsswitch.conf Look for the following three lines: passwd: files ldap shadow: files ldap group: files ldap If all three files are not configured to look for an LDAP source, then the system is not using LDAP for authentication. If the system is not using LDAP for authentication, this is not applicable. Check for the "bindpw" option being used in the "/etc/ldap.conf" file. # grep bindpw /etc/ldap.conf If an uncommented "bindpw" option is returned, then a cleartext password is in the file, and this is a finding.

Fix: F-31678r1_fix

Edit the "/etc/ldap.conf" file to use anonymous binding by removing the "bindpw" option.

c

The telnet daemon must not be running.

IA-5 - High - CCI-000197 - V-24386 - SV-37444r1_rule

RMF Control

IA-5

Severity

H

CCI

CCI-000197

Version

GEN003850

Vuln IDs

V-24386

Rule IDs

SV-37444r1_rule

The telnet daemon provides a typically unencrypted remote access service which does not provide for the confidentiality and integrity of user passwords or the remote session. If a privileged user were to log on using this service, the privileged user password could be compromised.GEN003850If an enabled telnet daemon is configured to only allow encrypted sessions, such as with Kerberos or the use of encrypted network tunnels, the risk of exposing sensitive information is mitigated, and this is not a finding.System AdministratorDCPP-1

Checks: C-36116r2_chk

The telnet service included in the RHEL distribution is part of krb5-workstation. There are two versions of telnetd server provided. The xinetd.d file ekrb5-telnet allows only connections authenticated through kerberos. The xinetd.d krb5-telnet allows normal telnet connections as well as kerberized connections. Both are set to "disable = yes" by default. Ensure that neither is running. Procedure: Check if telnetd is running: # ps -ef |grep telnetd If the telnet daemon is running, this is a finding. Check if telnetd is enabled on startup: # chkconfig --list|grep telnet If an entry with "on" is found, this is a finding.

Fix: F-31362r2_fix

Identify the telnet service running and disable it. Procedure: Disable the telnet server. # chkconfig telnet off Verify the telnet daemon is no longer running. # ps -ef |grep telnet

b

The system boot loader must protect passwords using an MD5 or stronger cryptographic hash.

AC-3 - Medium - CCI-000213 - V-24624 - SV-37938r1_rule

RMF Control

AC-3

Severity

M

CCI

Version

GEN008710

Vuln IDs

V-24624

Rule IDs

SV-37938r1_rule

If system boot loader passwords are compromised, users with console access to the system may be able to alter the system boot configuration or boot the system into single user or maintenance mode, which could result in Denial of Service or unauthorized privileged access to the system.System AdministratorIAIA-1, IAIA-2

Checks: C-37206r2_chk

Check GRUB for password configuration. Procedure: Check the /boot/grub/grub.conf or /boot/grub/menu.lst files. # grep "password" /boot/grub/grub.conf /boot/grub/menu.lst Check for a password configuration line, such as: password --md5 <password-hash> If the boot loader passwords are not protected using an MD5 hash or stronger, this is a finding.

Fix: F-27516r1_fix

Consult vendor documentation for procedures concerning the system's boot loader. Configure the boot loader to hash boot loader passwords using MD5 or a stronger hash.

b

A file integrity baseline including cryptographic hashes must be created.

CM-2 - Medium - CCI-000293 - V-27250 - SV-34549r3_rule

RMF Control

CM-2

Severity

M

CCI

CCI-000293

Version

GEN000140-2

Vuln IDs

V-27250

Rule IDs

SV-34549r3_rule

A file integrity baseline is a collection of file metadata that is to evaluate the integrity of the system. A minimal baseline must contain metadata for all device files, setuid files, setgid files, system libraries, system binaries, and system configuration files. The minimal metadata must consist of the mode, owner, group owner, and modification times. For regular files, metadata must also include file size and a cryptographic hash of the file's contents. System Administrator

Checks: C-37553r4_chk

Verify a system integrity baseline exists. The Advanced Intrusion Detection Environment (AIDE) is included in the distribution of RHEL. Other host intrusion detection system (HIDS) software is available but must be checked manually. Procedure: # grep DBDIR /etc/aide.conf If /etc/aide.conf does not exist AIDE has not been installed. Unless another HIDS is used on the system, this is a finding. Examine the response for "database" this indicates the location of the system integrity baseline database used as input to a comparison. # ls -la <DBDIR> If no "database" file as defined in /etc/aide.conf exists a system integrity baseline has not been created, this is a finding. Examine /etc/aide.conf to ensure some form of cryptographic hash (i.e. md5,rmd160,sha256) is used for files. In the default /etc/aide.conf the "NORMAL" or "LSPP" rules which are used for virtually all files DO include some form of cryptographic hash. If the site has defined rules to replace the functionality provided by the default "NORMAL" and "LSPP" rules but DOES NOT include cryptographic hashes, this is a finding. Otherwise, if any element used to define the "NORMAL" and "LSPP" rules has been modified resulting in cryptographic hashes not being used, this is a finding. If any other modification to the default /etc/aide.conf file have been made resulting in rules which do not include cryptographic hashes on appropriate files, this is a finding.

Fix: F-32799r4_fix

Use AIDE to create a file integrity baseline, including cryptographic hashes, for the system. Configure the /etc/aide.conf file to ensure some form of cryptographic hash (e.g., md5,rmd160,sha256) is used for files. In the default /etc/aide.conf the "NORMAL" or "LSPP" rules which are used for virtually all files DO include some form of cryptographic hash.

b

A file integrity baseline including cryptographic hashes must be maintained.

CM-2 - Medium - CCI-000293 - V-27251 - SV-34550r2_rule

RMF Control

CM-2

Severity

M

CCI

CCI-000293

Version

GEN000140-3

Vuln IDs

V-27251

Rule IDs

SV-34550r2_rule

A file integrity baseline is a collection of file metadata that is to evaluate the integrity of the system. A minimal baseline must contain metadata for all device files, setuid files, setgid files, system libraries, system binaries, and system configuration files. The minimal metadata must consist of the mode, owner, group owner, and modification times. For regular files, metadata must also include file size and a cryptographic hash of the file's contents. System Administrator

Checks: C-37565r1_chk

Verify a system integrity baseline is maintained. The baseline has been updated to be consistent with the latest approved system configuration changes. The Advanced Intrusion Detection Environment (AIDE) is included in the distribution of RHEL-5. Other host intrusion detection system (HIDS) software is available but must be checked manually. Procedure: # grep DBDIR /etc/aide.conf If /etc/aide.conf does not exist AIDE has not been installed. Unless another HIDS is used on the system, this is a finding. Examine the response for "database" indicates the location of the system integrity baseline database used as input to a comparison. # ls -la <DBDIR> If the no "database" file as defined in /etc/aide.conf a system integrity baseline has not been created, this is a finding. Ask the SA when the last approved system configuration changes occurred. If the modification date of the AIDE database is prior to the last approved configuration change, this is a finding.

Fix: F-32808r1_fix

Regularly rebuild the integrity baseline, including cryptographic hashes, for the system to be consistent with the latest approved system configuration. Procedure: After an approved modification to the system configuration has been made perform: # aide -u This will update the database.

b

The system must not have the unnecessary "news" account.

AC-2 - Medium - CCI-000012 - V-27275 - SV-34574r1_rule

RMF Control

AC-2

Severity

M

CCI

Version

GEN000290-2

Vuln IDs

V-27275

Rule IDs

SV-34574r1_rule

Accounts that provide no operational purpose provide additional opportunities for system compromise. Unnecessary accounts include user accounts for individuals not requiring access to the system and application accounts for applications not installed on the system.System AdministratorIAAC-1

Checks: C-37783r1_chk

Check the system for the unnecessary "news" accounts. Procedure: # rpm -q inn If the "inn" is installed the "news" user is necessary and this is not a finding. # grep ^news /etc/passwd If this account exists and "inn" is not installed, this is a finding.

Fix: F-33038r1_fix

Remove the "news" account from the /etc/passwd file before connecting a system to the network.

b

The system must not have the unnecessary "gopher" account.

AC-2 - Medium - CCI-000012 - V-27276 - SV-34575r1_rule

RMF Control

AC-2

Severity

M

CCI

Version

GEN000290-3

Vuln IDs

V-27276

Rule IDs

SV-34575r1_rule

Accounts that provide no operational purpose provide additional opportunities for system compromise. Unnecessary accounts include user accounts for individuals not requiring access to the system and application accounts for applications not installed on the system.System AdministratorIAAC-1

Checks: C-37784r1_chk

Check the system for the unnecessary "gopher" accounts. Procedure: # grep ^gopher /etc/passwd If this account exists, it is a finding.

Fix: F-33039r1_fix

Remove the "gopher" account from the /etc/passwd file before connecting a system to the network.

b

The system must not have the unnecessary "ftp" account.

AC-2 - Medium - CCI-000012 - V-27279 - SV-34578r1_rule

RMF Control

AC-2

Severity

M

CCI

Version

GEN000290-4

Vuln IDs

V-27279

Rule IDs

SV-34578r1_rule

Accounts that provide no operational purpose provide additional opportunities for system compromise. Unnecessary accounts include user accounts for individuals not requiring access to the system and application accounts for applications not installed on the system.System AdministratorIAAC-1

Checks: C-37785r1_chk

Check the system for the unnecessary "ftp" accounts. Procedure: # rpm -q krb5-workstation An ftp server is part of "krb5-workstation". If it is installed the "ftp" user is necessary and this is not a finding. # rpm -q vsftp If the "vsftp" ftp server is installed the "ftp" user is necessary and this is not a finding. # grep ^ftp /etc/passwd If this account exists and no ftp server is installed which requires it, this is a finding.

Fix: F-33040r1_fix

Remove the "ftp" account from the /etc/passwd file before connecting a system to the network.

b

The graphical desktop environment must set the idle timeout to no more than 15 minutes.

AC-11 - Medium - CCI-000057 - V-27283 - SV-48550r1_rule

RMF Control

AC-11

Severity

M

CCI

CCI-000057

Version

GEN000500-2

Vuln IDs

V-27283

Rule IDs

SV-48550r1_rule

If graphical desktop sessions do not lock the session after 15 minutes of inactivity, requiring re-authentication to resume operations, the system or individual data could be compromised by an alert intruder who could exploit the oversight. This requirement applies to graphical desktop environments provided by the system to locally attached displays and input devices as well as to graphical desktop environments provided to remote systems, including thin clients.System Administrator

Checks: C-45193r2_chk

If the "xorg-x11-server-Xorg" package is not installed, this is not applicable. For the Gnome screen saver, check the idle_delay setting. Procedure: # gconftool-2 --direct --config-source xml:readwrite:/etc/gconf/gconf.xml.mandatory --get /apps/gnome-screensaver/idle_delay If this does not return 15 or less, this is a finding.

Fix: F-33041r1_fix

For the Gnome screen saver, set idle_delay to 15. Procedure: # gconftool-2 --direct --config-source xml:readwrite:/etc/gconf/gconf.xml.mandatory --type int --set /apps/gnome-screensaver/idle_delay 15

b

Graphical desktop environments provided by the system must have automatic lock enabled.

AC-11 - Medium - CCI-000057 - V-27284 - SV-48551r1_rule

RMF Control

AC-11

Severity

M

CCI

CCI-000057

Version

GEN000500-3

Vuln IDs

V-27284

Rule IDs

SV-48551r1_rule

If graphical desktop sessions do not lock the session after 15 minutes of inactivity, requiring re-authentication to resume operations, the system or individual data could be compromised by an alert intruder who could exploit the oversight. This requirement applies to graphical desktop environments provided by the system to locally attached displays and input devices as well as to graphical desktop environments provided to remote systems, including thin clients.System Administrator

Checks: C-45195r1_chk

If the "xorg-x11-server-Xorg" package is not installed, this is not applicable. For the Gnome screen saver, check the lock_enabled flag. Procedure: # gconftool-2 --direct --config-source xml:readwrite:/etc/gconf/gconf.xml.mandatory --get /apps/gnome-screensaver/lock_enabled If this does not return "true", this is a finding.

Fix: F-33042r1_fix

For the Gnome screen saver, set the lock_enabled flag. Procedure: # gconftool-2 --direct --config-source xml:readwrite:/etc/gconf/gconf.xml.mandatory --type bool --set /apps/gnome-screensaver/lock_enabled true

b

Global settings defined in system-auth must be applied in the pam.d definition files.

IA-5 - Medium - CCI-000192 - V-27285 - SV-34584r1_rule

RMF Control

IA-5

Severity

M

CCI

CCI-000192

Version

GEN000600-2

Vuln IDs

V-27285

Rule IDs

SV-34584r1_rule

Pam global requirements are generally defined in the /etc/pam.d/system-auth or /etc/pam.d/system-auth-ac file. In order for the requirements to be applied the file containing them must be included directly or indirectly in each program's definition file in /etc/pam.d System AdministratorECSC-1

Checks: C-37566r3_chk

Verify the system-auth settings are being applied. Procedure: Verify the additional pam.d requirements are in use. The file "/etc/pam.d/system-auth-ac" is auto generated by "authconfig". Any manual changes made to it will be lost next time "authconfig" is run. Check to see if the systems default of the symlink "/etc/pam.d/system-auth" pointing to "/etc/pam.d/system-auth-ac" has been changed. # ls -l /etc/pam.d/system-auth If the symlink points to "/etc/pam.d/system-auth-ac", manual changes cannot be protected. This is a finding. # grep system-auth-ac /etc/pam.d/system-auth The local system-auth file pointed to by "/etc/pam.d/system-auth" must contain "/etc/pam.d/system-auth-ac" for the auth, account, password, and session lines. If it does not then the parameters maintained by "authconfig" will not be applied, this is a finding.

Fix: F-32809r2_fix

In the default distribution of RHEL "/etc/pam.d/system-auth" is a symlink "/etc/pam.d/system-auth-ac" which is an autogenerated file. When a site adds password requirements a new system-auth-local file must be created with only the additional requirements and includes for auth, account, passwd and session pointing to "/etc/pam.d/system-auth-ac". Then the symlink "/etc/system-auth" is modified to point to "/etc/pam.d/system-auth-local". This way any changes made do not get lost when "/etc/pam.d/system-auth-ac" is regenerated and each program's pam.d definition file need only have "include system-auth" for auth, account, passwd and session, as needed, in order to assure the password requirements will be applied to it.

b

The audit system must be configured to audit failed attempts to access files and programs.

AU-2 - Medium - CCI-000126 - V-29236 - SV-37612r2_rule

RMF Control

AU-2

Severity

M

CCI

Version

GEN002720-2

Vuln IDs

V-29236

Rule IDs

SV-37612r2_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System Administrator

Checks: C-36810r2_chk

Check that auditd is configured to audit failed file access attempts. There must be an audit rule for each of the access syscalls that logs all failed accesses (-F success=0) or there must both an "-F exit=-EPERM" and "-F exit=-EACCES" for each access syscall. Procedure: # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -e "-S open" | grep -e "-F success=0" # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -e "-S open" | grep -e "-F exit=-EPERM" # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -e "-S open" | grep -e "-F exit=-EACCES" If an "-S open" audit rule with "-F success" does not exist and no separate rules containing "-F exit=-EPERM" and "-F exit=-EACCES" for "open" exist, then this is a finding.

Fix: F-31649r1_fix

Edit the audit.rules file and add the following line(s) to enable auditing of failed attempts to access files and programs: either: -a exit,always -F arch=<ARCH> -S open -F success=0 or both: -a exit,always -F arch=<ARCH> -S open -F exit=-EPERM -a exit,always -F arch=<ARCH> -S open -F exit=-EACCES Restart the auditd service. # service auditd restart

b

The audit system must be configured to audit failed attempts to access files and programs.

AU-2 - Medium - CCI-000126 - V-29237 - SV-37614r2_rule

RMF Control

AU-2

Severity

M

CCI

Version

GEN002720-3

Vuln IDs

V-29237

Rule IDs

SV-37614r2_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System Administrator

Checks: C-36812r2_chk

Verify auditd is configured to audit failed file access attempts. There must be an audit rule for each of the access syscalls logging all failed accesses (-F success=0) or there must both an "-F exit=-EPERM" and "-F exit=-EACCES" for each access syscall. Procedure: # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -e "-S openat" | grep -e "-F success=0" # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -e "-S openat" | grep -e "-F exit=-EPERM" # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -e "-S openat" | grep -e "-F exit=-EACCES" If an "-S openat" audit rule with "-F success" does not exist and no separate rules containing "-F exit=-EPERM" and "-F exit=-EACCES" for "openat" exist, then this is a finding.

Fix: F-31650r1_fix

Edit the audit.rules file and add the following line(s) to enable auditing of failed attempts to access files and programs: either: -a exit,always -F arch=<ARCH> -S openat -F success=0 or both: -a exit,always -F arch=<ARCH> -S openat -F exit=-EPERM -a exit,always -F arch=<ARCH> -S openat -F exit=-EACCES Restart the auditd service. # service auditd restart

b

The audit system must be configured to audit failed attempts to access files and programs.

AU-2 - Medium - CCI-000126 - V-29238 - SV-37654r2_rule

RMF Control

AU-2

Severity

M

CCI

Version

GEN002720-4

Vuln IDs

V-29238

Rule IDs

SV-37654r2_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System Administrator

Checks: C-36844r2_chk

Verify auditd is configured to audit failed file access attempts. There must be an audit rule for each of the access syscalls logging all failed accesses (-F success=0) or there must both an "-F exit=-EPERM" and "-F exit=-EACCES" for each access syscall. Procedure: # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -e "-S truncate" | grep -e "-F success=0" # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -e "-S truncate" | grep -e "-F exit=-EPERM" # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -e "-S truncate" | grep -e "-F exit=-EACCES" If an "-S truncate" audit rule with "-F success" does not exist and no separate rules containing "-F exit=-EPERM" and "-F exit=-EACCES" for "truncate" exist, then this is a finding.

Fix: F-31681r1_fix

Edit the audit.rules file and add the following line(s) to enable auditing of failed attempts to access files and programs: either: -a exit,always -F arch=<ARCH> -S truncate -F success=0 or both: -a exit,always -F arch=<ARCH> -S truncate -F exit=-EPERM -a exit,always -F arch=<ARCH> -S truncate -F exit=-EACCES Restart the auditd service. # service auditd restart

b

The audit system must be configured to audit failed attempts to access files and programs.

AU-2 - Medium - CCI-000126 - V-29239 - SV-37655r2_rule

RMF Control

AU-2

Severity

M

CCI

Version

GEN002720-5

Vuln IDs

V-29239

Rule IDs

SV-37655r2_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System Administrator

Checks: C-36845r2_chk

Verify auditd is configured to audit failed file access attempts. There must be an audit rule for each of the access syscalls logging all failed accesses (-F success=0) or there must both an "-F exit=-EPERM" and "-F exit=-EACCES" for each access syscall. Procedure: # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -e "-S ftruncate" | grep -e "-F success=0" # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -e "-S ftruncate" | grep -e "-F exit=-EPERM" # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -e "-S ftruncate" | grep -e "-F exit=-EACCES" If an "-S ftruncate" audit rule with "-F success" does not exist and no separate rules containing "-F exit=-EPERM" and "-F exit=-EACCES" for "ftruncate" exist, then this is a finding.

Fix: F-31682r1_fix

Edit the audit.rules file and add the following line(s) to enable auditing of failed attempts to access files and programs: either: -a exit,always -F arch=<ARCH> -S ftruncate -F success=0 or both: -a exit,always -F arch=<ARCH> -S ftruncate -F exit=-EPERM -a exit,always -F arch=<ARCH> -S ftruncate -F exit=-EACCES Restart the auditd service. # service auditd restart

b

The audit system must be configured to audit file deletions.

AU-2 - Medium - CCI-000126 - V-29240 - SV-37656r1_rule

RMF Control

AU-2

Severity

M

CCI

Version

GEN002740-2

Vuln IDs

V-29240

Rule IDs

SV-37656r1_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System AdministratorECAR-1, ECAR-2, ECAR-3

Checks: C-36846r1_chk

Check the system audit configuration to determine if file and directory deletions are audited. # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -i "rmdir" If no results are returned, or the results do not contain "-S rmdir", this is a finding.

Fix: F-31683r1_fix

Edit the audit.rules file and add the following line to enable auditing of deletions: -a exit,always -S rmdir Restart the auditd service. # service auditd restart

b

The audit system must be configured to audit all administrative, privileged, and security actions.

CM-5 - Medium - CCI-000347 - V-29241 - SV-48474r1_rule

RMF Control

CM-5

Severity

M

CCI

Version

GEN002760-2

Vuln IDs

V-29241

Rule IDs

SV-48474r1_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System Administrator

Checks: C-36847r1_chk

Check the auditing configuration of the system. Procedure: # cat /etc/audit/audit.rules | grep -i "audit.rules" If no results are returned, or the line does not start with "-w", this is a finding.

Fix: F-41610r1_fix

The use of audit keys consistent with the provided example is encouraged to provide for uniform audit logs, however omitting the audit key or using an alternate audit key is not a finding. Procedure: Add the following lines to the audit.rules file to enable auditing of administrative, privileged, and security actions: -w /etc/audit/audit.rules Restart the auditd service. # service auditd restart

b

The audit system must be configured to audit all administrative, privileged, and security actions.

CM-5 - Medium - CCI-000347 - V-29242 - SV-37658r2_rule

RMF Control

CM-5

Severity

M

CCI

Version

GEN002760-3

Vuln IDs

V-29242

Rule IDs

SV-37658r2_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System Administrator

Checks: C-36848r5_chk

Check the auditing configuration of the system. Procedure: # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -i "adjtimex" If the result does not contain "-S adjtimex", this is a finding.

Fix: F-31685r4_fix

The "-F arch=<ARCH>"restriction is required on dual-architecture systems (such as x86_64). On dual-architecture systems, two separate rules must exist - one for each architecture supported. Use the generic architectures "b32" and "b64" for specifying these rules. On single architecture systems, the "-F arch=<ARCH>"restriction may be omitted, but if present must match either the architecture of the system or its corresponding generic architecture. The architecture of the system may be determined by running "uname -m". See the auditctl(8) manpage for additional details. Any restrictions (such as with "-F") beyond those provided in the example rules are not in strict compliance with this requirement, and are a finding unless justified and documented appropriately. The use of audit keys consistent with the provided example is encouraged to provide for uniform audit logs, however omitting the audit key or using an alternate audit key is not a finding. Procedure: Add the following lines to the audit.rules file to enable auditing of administrative, privileged, and security actions: -a exit,always -F arch=<ARCH> -S adjtimex Restart the auditd service. # service auditd restart

b

The audit system must be configured to audit all administrative, privileged, and security actions.

CM-5 - Medium - CCI-000347 - V-29243 - SV-37659r1_rule

RMF Control

CM-5

Severity

M

CCI

Version

GEN002760-4

Vuln IDs

V-29243

Rule IDs

SV-37659r1_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System AdministratorECAR-1, ECAR-2, ECAR-3

Checks: C-36849r1_chk

Check the auditing configuration of the system. Procedure: # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -i "settimeofday" If the result does not contain "-S settimeofday", this is a finding.

Fix: F-31686r1_fix

The "-F arch=<ARCH>"restriction is required on dual-architecture systems (such as x86_64). On dual-architecture systems, two separate rules must exist - one for each architecture supported. Use the generic architectures "b32" and "b64" for specifying these rules. On single architecture systems, the "-F arch=<ARCH>"restriction may be omitted, but if present must match either the architecture of the system or its corresponding generic architecture. The architecture of the system may be determined by running "uname -m". See the auditctl(8) manpage for additional details. Any restrictions (such as with "-F") beyond those provided in the example rules are not in strict compliance with this requirement, and are a finding unless justified and documented appropriately. The use of audit keys consistent with the provided example is encouraged to provide for uniform audit logs, however omitting the audit key or using an alternate audit key is not a finding. Procedure: Add the following lines to the audit.rules file to enable auditing of administrative, privileged, and security actions: -a exit,always -F arch=<ARCH> -S settimeofday Restart the auditd service. # service auditd restart

b

The audit system must be configured to audit all administrative, privileged, and security actions.

CM-5 - Medium - CCI-000347 - V-29244 - SV-37660r3_rule

RMF Control

CM-5

Severity

M

CCI

Version

GEN002760-5

Vuln IDs

V-29244

Rule IDs

SV-37660r3_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System Administrator

Checks: C-36949r4_chk

Check the auditing configuration of the system. Procedure: # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -i "stime" # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -i "settimeofday" If the result does not contain "-S stime" or "-S settimeofday ", this is a finding. The "stime" keyword is only required on systems using an i386 architecture.

Fix: F-32213r3_fix

The "-F arch=<ARCH>"restriction is required on dual-architecture systems (such as x86_64). On dual-architecture systems, two separate rules must exist - one for each architecture supported. Use the generic architectures "b32" and "b64" for specifying these rules. On single architecture systems, the "-F arch=<ARCH>"restriction may be omitted, but if present must match either the architecture of the system or its corresponding generic architecture. The architecture of the system may be determined by running "uname -m". See the auditctl(8) manpage for additional details. Any restrictions (such as with "-F") beyond those provided in the example rules are not in strict compliance with this requirement, and are a finding unless justified and documented appropriately. The use of audit keys consistent with the provided example is encouraged to provide for uniform audit logs, however omitting the audit key or using an alternate audit key is not a finding. Procedure: Add the following lines to the audit.rules file to enable auditing of administrative, privileged, and security actions: -a exit,always -F arch=<ARCH> -S stime (only used for systems using an i386 architecture) -a exit,always -F arch=<ARCH> -S settimeofday (used on all non-i386 architectures such as b64 and x86_64) Restart the auditd service. # service auditd restart

b

The audit system must be configured to audit all administrative, privileged, and security actions.

CM-5 - Medium - CCI-000347 - V-29245 - SV-37661r1_rule

RMF Control

CM-5

Severity

M

CCI

Version

GEN002760-6

Vuln IDs

V-29245

Rule IDs

SV-37661r1_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System AdministratorECAR-1, ECAR-2, ECAR-3

Checks: C-36850r1_chk

Check the auditing configuration of the system. Procedure: # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -i "clock_settime" If the result does not contain "-S clock_settime", this is a finding.

Fix: F-31687r1_fix

The "-F arch=<ARCH>"restriction is required on dual-architecture systems (such as x86_64). On dual-architecture systems, two separate rules must exist - one for each architecture supported. Use the generic architectures "b32" and "b64" for specifying these rules. On single architecture systems, the "-F arch=<ARCH>"restriction may be omitted, but if present must match either the architecture of the system or its corresponding generic architecture. The architecture of the system may be determined by running "uname -m". See the auditctl(8) manpage for additional details. Any restrictions (such as with "-F") beyond those provided in the example rules are not in strict compliance with this requirement, and are a finding unless justified and documented appropriately. The use of audit keys consistent with the provided example is encouraged to provide for uniform audit logs, however omitting the audit key or using an alternate audit key is not a finding. Procedure: Add the following lines to the audit.rules file to enable auditing of administrative, privileged, and security actions: -a exit,always -F arch=<ARCH> -S clock_settime Restart the auditd service. # service auditd restart

b

The audit system must be configured to audit all administrative, privileged, and security actions.

CM-5 - Medium - CCI-000347 - V-29246 - SV-37662r1_rule

RMF Control

CM-5

Severity

M

CCI

Version

GEN002760-7

Vuln IDs

V-29246

Rule IDs

SV-37662r1_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System AdministratorECAR-1, ECAR-2, ECAR-3

Checks: C-36851r1_chk

Check the auditing configuration of the system. Procedure: # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -i "sethostname" If the result does not contain "-S sethostname", this is a finding.

Fix: F-31688r1_fix

The "-F arch=<ARCH>"restriction is required on dual-architecture systems (such as x86_64). On dual-architecture systems, two separate rules must exist - one for each architecture supported. Use the generic architectures "b32" and "b64" for specifying these rules. On single architecture systems, the "-F arch=<ARCH>"restriction may be omitted, but if present must match either the architecture of the system or its corresponding generic architecture. The architecture of the system may be determined by running "uname -m". See the auditctl(8) manpage for additional details. Any restrictions (such as with "-F") beyond those provided in the example rules are not in strict compliance with this requirement, and are a finding unless justified and documented appropriately. The use of audit keys consistent with the provided example is encouraged to provide for uniform audit logs, however omitting the audit key or using an alternate audit key is not a finding. Procedure: Add the following lines to the audit.rules file to enable auditing of administrative, privileged, and security actions: -a exit,always -F arch=<ARCH> -S sethostname Restart the auditd service. # service auditd restart

b

The audit system must be configured to audit all administrative, privileged, and security actions.

CM-5 - Medium - CCI-000347 - V-29247 - SV-37663r1_rule

RMF Control

CM-5

Severity

M

CCI

Version

GEN002760-8

Vuln IDs

V-29247

Rule IDs

SV-37663r1_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System AdministratorECAR-1, ECAR-2, ECAR-3

Checks: C-36852r1_chk

Check the auditing configuration of the system. Procedure: # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -i "setdomain" If the result does not contain "-S setdomain", this is a finding.

Fix: F-31689r1_fix

The "-F arch=<ARCH>"restriction is required on dual-architecture systems (such as x86_64). On dual-architecture systems, two separate rules must exist - one for each architecture supported. Use the generic architectures "b32" and "b64" for specifying these rules. On single architecture systems, the "-F arch=<ARCH>"restriction may be omitted, but if present must match either the architecture of the system or its corresponding generic architecture. The architecture of the system may be determined by running "uname -m". See the auditctl(8) manpage for additional details. Any restrictions (such as with "-F") beyond those provided in the example rules are not in strict compliance with this requirement, and are a finding unless justified and documented appropriately. The use of audit keys consistent with the provided example is encouraged to provide for uniform audit logs, however omitting the audit key or using an alternate audit key is not a finding. Procedure: Add the following lines to the audit.rules file to enable auditing of administrative, privileged, and security actions: -a exit,always -F arch=<ARCH> -S setdomainname Restart the auditd service. # service auditd restart

b

The audit system must be configured to audit all administrative, privileged, and security actions.

CM-5 - Medium - CCI-000347 - V-29248 - SV-37664r1_rule

RMF Control

CM-5

Severity

M

CCI

Version

GEN002760-9

Vuln IDs

V-29248

Rule IDs

SV-37664r1_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System AdministratorECAR-1, ECAR-2, ECAR-3

Checks: C-36853r1_chk

Check the auditing configuration of the system. Procedure: # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -i "sched_setparam" If the result does not contain "-S sched_setparam", this is a finding.

Fix: F-31690r1_fix

The "-F arch=<ARCH>"restriction is required on dual-architecture systems (such as x86_64). On dual-architecture systems, two separate rules must exist - one for each architecture supported. Use the generic architectures "b32" and "b64" for specifying these rules. On single architecture systems, the "-F arch=<ARCH>"restriction may be omitted, but if present must match either the architecture of the system or its corresponding generic architecture. The architecture of the system may be determined by running "uname -m". See the auditctl(8) manpage for additional details. Any restrictions (such as with "-F") beyond those provided in the example rules are not in strict compliance with this requirement, and are a finding unless justified and documented appropriately. The use of audit keys consistent with the provided example is encouraged to provide for uniform audit logs, however omitting the audit key or using an alternate audit key is not a finding. Procedure: A Real Time Operating System (RTOS) provides specialized system scheduling which causes an inordinate number of messages to be produced when the sched_setparam and set_setscheduler are audited. This not only may degrade the system speed to an unusable level but obscures any forensic information which may otherwise have been useful. Unless the operating system is a Red Hat 5 based RTOS (including MRG and AS5300) the following should also be present in /etc/audit/audit.rules -a exit,always -F arch=<ARCH> -S sched_setparam Restart the auditd service. # service auditd restart

b

The audit system must be configured to audit all administrative, privileged, and security actions.

CM-5 - Medium - CCI-000347 - V-29249 - SV-37665r1_rule

RMF Control

CM-5

Severity

M

CCI

Version

GEN002760-10

Vuln IDs

V-29249

Rule IDs

SV-37665r1_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System AdministratorECAR-1, ECAR-2, ECAR-3

Checks: C-36854r1_chk

Check the auditing configuration of the system. Procedure: # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -i "sched_setscheduler" If the result does not contain "-S sched_setscheduler", this is a finding.

Fix: F-31691r1_fix

The "-F arch=<ARCH>"restriction is required on dual-architecture systems (such as x86_64). On dual-architecture systems, two separate rules must exist - one for each architecture supported. Use the generic architectures "b32" and "b64" for specifying these rules. On single architecture systems, the "-F arch=<ARCH>"restriction may be omitted, but if present must match either the architecture of the system or its corresponding generic architecture. The architecture of the system may be determined by running "uname -m". See the auditctl(8) manpage for additional details. Any restrictions (such as with "-F") beyond those provided in the example rules are not in strict compliance with this requirement, and are a finding unless justified and documented appropriately. The use of audit keys consistent with the provided example is encouraged to provide for uniform audit logs, however omitting the audit key or using an alternate audit key is not a finding. Procedure: A Real Time Operating System (RTOS) provides specialized system scheduling which causes an inordinate number of messages to be produced when the sched_setparam and set_setscheduler are audited. This not only may degrade the system speed to an unusable level but obscures any forensic information which may otherwise have been useful. Unless the operating system is a Red Hat 5 based RTOS (including MRG and AS5300) the following should also be present in /etc/audit/audit.rules -a exit,always -F arch=<ARCH> -S sched_setscheduler Restart the auditd service. # service auditd restart

b

The audit system must be configured to audit all discretionary access control permission modifications.

AU-2 - Medium - CCI-000126 - V-29250 - SV-37666r1_rule

RMF Control

AU-2

Severity

M

CCI

Version

GEN002820-2

Vuln IDs

V-29250

Rule IDs

SV-37666r1_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System AdministratorECAR-1, ECAR-2, ECAR-3

Checks: C-36855r1_chk

Check the system's audit configuration. Procedure: # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -i "fchmod" If "-S fchmod" is not in the result, this is a finding

Fix: F-31692r2_fix

The "-F arch=<ARCH>" restriction is required on dual-architecture systems (such as x86_64). On dual-architecture systems, two separate rules must exist - one for each architecture supported. Use the generic architectures "b32" and "b64" for specifying these rules. On single architecture systems, the "-F arch=<ARCH>" restriction may be omitted, but if present must match either the architecture of the system or its corresponding generic architecture. The architecture of the system may be determined by running "uname -m". See the auditctl(8) manpage for additional details. Any restrictions (such as with "-F") beyond those provided in the example rules are not in strict compliance with this requirement, and are a finding unless justified and documented appropriately. The use of audit keys consistent with the provided example is encouraged to provide for uniform audit logs, however omitting the audit key or using an alternate audit key is not a finding. Procedure: Edit the audit.rules file and add the following lines to enable auditing of discretionary access control permissions modifications. -a exit,always -F arch=<ARCH> -S fchmod Restart the auditd service. # service auditd restart

b

The audit system must be configured to audit all discretionary access control permission modifications.

AU-2 - Medium - CCI-000126 - V-29251 - SV-37667r1_rule

RMF Control

AU-2

Severity

M

CCI

Version

GEN002820-3

Vuln IDs

V-29251

Rule IDs

SV-37667r1_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System AdministratorECAR-1, ECAR-2, ECAR-3

Checks: C-36856r1_chk

Check the system's audit configuration. Procedure: # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -i "fchmodat" If "-S fchmodat" is not in the result, this is a finding.

Fix: F-31695r1_fix

The "-F arch=<ARCH>" restriction is required on dual-architecture systems (such as x86_64). On dual-architecture systems, two separate rules must exist - one for each architecture supported. Use the generic architectures "b32" and "b64" for specifying these rules. On single architecture systems, the "-F arch=<ARCH>" restriction may be omitted, but if present must match either the architecture of the system or its corresponding generic architecture. The architecture of the system may be determined by running "uname -m". See the auditctl(8) manpage for additional details. Any restrictions (such as with "-F") beyond those provided in the example rules are not in strict compliance with this requirement, and are a finding unless justified and documented appropriately. The use of audit keys consistent with the provided example is encouraged to provide for uniform audit logs, however omitting the audit key or using an alternate audit key is not a finding. Procedure: Edit the audit.rules file and add the following lines to enable auditing of discretionary access control permissions modifications. -a exit,always -F arch=<ARCH> -S fchmodat Restart the auditd service. # service auditd restart

b

The audit system must be configured to audit all discretionary access control permission modifications.

AU-2 - Medium - CCI-000126 - V-29252 - SV-37668r1_rule

RMF Control

AU-2

Severity

M

CCI

Version

GEN002820-4

Vuln IDs

V-29252

Rule IDs

SV-37668r1_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System AdministratorECAR-1, ECAR-2, ECAR-3

Checks: C-36857r1_chk

Check the system's audit configuration. Procedure: # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -i "chown" If "-S chown" is not in the result, this is a finding. Additionally, the following rule is required in systems supporting the 32-bit syscall table (such as i686 and x86_64): # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -i "chown32" If "-S chown32" is not in the result, this is a finding.

Fix: F-31710r1_fix

The "-F arch=<ARCH>" restriction is required on dual-architecture systems (such as x86_64). On dual-architecture systems, two separate rules must exist - one for each architecture supported. Use the generic architectures "b32" and "b64" for specifying these rules. On single architecture systems, the "-F arch=<ARCH>" restriction may be omitted, but if present must match either the architecture of the system or its corresponding generic architecture. The architecture of the system may be determined by running "uname -m". See the auditctl(8) manpage for additional details. Any restrictions (such as with "-F") beyond those provided in the example rules are not in strict compliance with this requirement, and are a finding unless justified and documented appropriately. The use of audit keys consistent with the provided example is encouraged to provide for uniform audit logs, however omitting the audit key or using an alternate audit key is not a finding. Procedure: Edit the audit.rules file and add the following lines to enable auditing of discretionary access control permissions modifications. -a exit,always -F arch=<ARCH> -S chown Additionally, the following rule is required in systems supporting the 32-bit syscall table (such as i686 and x86_64): -a exit,always -F arch=<ARCH> -S chown32 Restart the auditd service. # service auditd restart

b

The audit system must be configured to audit all discretionary access control permission modifications.

AU-2 - Medium - CCI-000126 - V-29253 - SV-37669r1_rule

RMF Control

AU-2

Severity

M

CCI

Version

GEN002820-5

Vuln IDs

V-29253

Rule IDs

SV-37669r1_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System AdministratorECAR-1, ECAR-2, ECAR-3

Checks: C-36859r2_chk

Check the system's audit configuration. Procedure: # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -i "fchown" If "-S fchown" is not in the result, this is a finding. Additionally, the following rule is required in systems supporting the 32-bit syscall table (such as i686 and x86_64): # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -i "fchown32" If "-S fchown32" is not in the result, this is a finding.

Fix: F-31729r2_fix

The "-F arch=<ARCH>" restriction is required on dual-architecture systems (such as x86_64). On dual-architecture systems, two separate rules must exist - one for each architecture supported. Use the generic architectures "b32" and "b64" for specifying these rules. On single architecture systems, the "-F arch=<ARCH>" restriction may be omitted, but if present must match either the architecture of the system or its corresponding generic architecture. The architecture of the system may be determined by running "uname -m". See the auditctl(8) manpage for additional details. Any restrictions (such as with "-F") beyond those provided in the example rules are not in strict compliance with this requirement, and are a finding unless justified and documented appropriately. The use of audit keys consistent with the provided example is encouraged to provide for uniform audit logs, however omitting the audit key or using an alternate audit key is not a finding. Procedure: Edit the audit.rules file and add the following lines to enable auditing of discretionary access control permissions modifications. -a exit,always -F arch=<ARCH> -S fchown Additionally, the following rule is required in systems supporting the 32-bit syscall table (such as i686 and x86_64): -a exit,always -F arch=<ARCH> -S fchown32 Restart the auditd service. # service auditd restart

b

The audit system must be configured to audit all discretionary access control permission modifications.

AU-2 - Medium - CCI-000126 - V-29255 - SV-37671r1_rule

RMF Control

AU-2

Severity

M

CCI

Version

GEN002820-6

Vuln IDs

V-29255

Rule IDs

SV-37671r1_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System AdministratorECAR-1, ECAR-2, ECAR-3

Checks: C-36861r1_chk

Check the system's audit configuration. Procedure: # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -i "fchownat" If "-S fchownat" is not in the result, this is a finding.

Fix: F-31781r1_fix

The "-F arch=<ARCH>" restriction is required on dual-architecture systems (such as x86_64). On dual-architecture systems, two separate rules must exist - one for each architecture supported. Use the generic architectures "b32" and "b64" for specifying these rules. On single architecture systems, the "-F arch=<ARCH>" restriction may be omitted, but if present must match either the architecture of the system or its corresponding generic architecture. The architecture of the system may be determined by running "uname -m". See the auditctl(8) manpage for additional details. Any restrictions (such as with "-F") beyond those provided in the example rules are not in strict compliance with this requirement, and are a finding unless justified and documented appropriately. The use of audit keys consistent with the provided example is encouraged to provide for uniform audit logs, however omitting the audit key or using an alternate audit key is not a finding. Procedure: Edit the audit.rules file and add the following lines to enable auditing of discretionary access control permissions modifications. -a exit,always -F arch=<ARCH> -S fchownat Restart the auditd service. # service auditd restart

b

The audit system must be configured to audit all discretionary access control permission modifications.

AU-2 - Medium - CCI-000126 - V-29257 - SV-37673r1_rule

RMF Control

AU-2

Severity

M

CCI

Version

GEN002820-7

Vuln IDs

V-29257

Rule IDs

SV-37673r1_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System AdministratorECAR-1, ECAR-2, ECAR-3

Checks: C-36863r1_chk

Check the system's audit configuration. Procedure: # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -i "lchown" If "-S lchown" is not in the result, this is a finding. Additionally, the following rule is required in systems supporting the 32-bit syscall table (such as i686 and x86_64): # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -i "lchown32" If "-S lchown32" is not in the result, this is a finding.

Fix: F-31805r1_fix

The "-F arch=<ARCH>" restriction is required on dual-architecture systems (such as x86_64). On dual-architecture systems, two separate rules must exist - one for each architecture supported. Use the generic architectures "b32" and "b64" for specifying these rules. On single architecture systems, the "-F arch=<ARCH>" restriction may be omitted, but if present must match either the architecture of the system or its corresponding generic architecture. The architecture of the system may be determined by running "uname -m". See the auditctl(8) manpage for additional details. Any restrictions (such as with "-F") beyond those provided in the example rules are not in strict compliance with this requirement, and are a finding unless justified and documented appropriately. The use of audit keys consistent with the provided example is encouraged to provide for uniform audit logs, however omitting the audit key or using an alternate audit key is not a finding. Procedure: Edit the audit.rules file and add the following lines to enable auditing of discretionary access control permissions modifications. -a exit,always -F arch=<ARCH> -S lchown Additionally, the following rule is required in systems supporting the 32-bit syscall table (such as i686 and x86_64): -a exit,always -F arch=<ARCH> -S lchown32 Restart the auditd service. # service auditd restart

b

The audit system must be configured to audit all discretionary access control permission modifications.

AU-2 - Medium - CCI-000126 - V-29259 - SV-37677r1_rule

RMF Control

AU-2

Severity

M

CCI

Version

GEN002820-8

Vuln IDs

V-29259

Rule IDs

SV-37677r1_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System AdministratorECAR-1, ECAR-2, ECAR-3

Checks: C-36868r1_chk

Check the system's audit configuration. Procedure: # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -i "setxattr" If "-S setxattr" is not in the result, this is a finding.

Fix: F-31825r1_fix

The "-F arch=<ARCH>" restriction is required on dual-architecture systems (such as x86_64). On dual-architecture systems, two separate rules must exist - one for each architecture supported. Use the generic architectures "b32" and "b64" for specifying these rules. On single architecture systems, the "-F arch=<ARCH>" restriction may be omitted, but if present must match either the architecture of the system or its corresponding generic architecture. The architecture of the system may be determined by running "uname -m". See the auditctl(8) manpage for additional details. Any restrictions (such as with "-F") beyond those provided in the example rules are not in strict compliance with this requirement, and are a finding unless justified and documented appropriately. The use of audit keys consistent with the provided example is encouraged to provide for uniform audit logs, however omitting the audit key or using an alternate audit key is not a finding. Procedure: Edit the audit.rules file and add the following lines to enable auditing of discretionary access control permissions modifications. -a exit,always -F arch=<ARCH> -S setxattr Restart the auditd service. # service auditd restart

b

The audit system must be configured to audit all discretionary access control permission modifications.

Medium - V-29261 - SV-37681r1_rule

RMF Control

Severity

M

CCI

Version

GEN002820-9

Vuln IDs

V-29261

Rule IDs

SV-37681r1_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System AdministratorECAR-1, ECAR-2, ECAR-3

Checks: C-36870r1_chk

Check the system's audit configuration. Procedure: # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -i "lsetxattr" If "-S lsetxattr" is not in the result, this is a finding.

Fix: F-31843r1_fix

The "-F arch=<ARCH>" restriction is required on dual-architecture systems (such as x86_64). On dual-architecture systems, two separate rules must exist - one for each architecture supported. Use the generic architectures "b32" and "b64" for specifying these rules. On single architecture systems, the "-F arch=<ARCH>" restriction may be omitted, but if present must match either the architecture of the system or its corresponding generic architecture. The architecture of the system may be determined by running "uname -m". See the auditctl(8) manpage for additional details. Any restrictions (such as with "-F") beyond those provided in the example rules are not in strict compliance with this requirement, and are a finding unless justified and documented appropriately. The use of audit keys consistent with the provided example is encouraged to provide for uniform audit logs, however omitting the audit key or using an alternate audit key is not a finding. Procedure: Edit the audit.rules file and add the following lines to enable auditing of discretionary access control permissions modifications. -a exit,always -F arch=<ARCH> -S lsetxattr Restart the auditd service. # service auditd restart

b

The audit system must be configured to audit all discretionary access control permission modifications.

AU-2 - Medium - CCI-000126 - V-29272 - SV-37716r1_rule

RMF Control

AU-2

Severity

M

CCI

Version

GEN002820-10

Vuln IDs

V-29272

Rule IDs

SV-37716r1_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System AdministratorECAR-1, ECAR-2, ECAR-3

Checks: C-36919r1_chk

Check the system's audit configuration. Procedure: # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -i "fsetxattr" If "-S fsetxattr" is not in the result, this is a finding.

Fix: F-32185r1_fix

The "-F arch=<ARCH>" restriction is required on dual-architecture systems (such as x86_64). On dual-architecture systems, two separate rules must exist - one for each architecture supported. Use the generic architectures "b32" and "b64" for specifying these rules. On single architecture systems, the "-F arch=<ARCH>" restriction may be omitted, but if present must match either the architecture of the system or its corresponding generic architecture. The architecture of the system may be determined by running "uname -m". See the auditctl(8) manpage for additional details. Any restrictions (such as with "-F") beyond those provided in the example rules are not in strict compliance with this requirement, and are a finding unless justified and documented appropriately. The use of audit keys consistent with the provided example is encouraged to provide for uniform audit logs, however omitting the audit key or using an alternate audit key is not a finding. Procedure: Edit the audit.rules file and add the following lines to enable auditing of discretionary access control permissions modifications. -a exit,always -F arch=<ARCH> -S fsetxattr Restart the auditd service. # service auditd restart

b

The audit system must be configured to audit all discretionary access control permission modifications.

AU-2 - Medium - CCI-000126 - V-29274 - SV-37718r1_rule

RMF Control

AU-2

Severity

M

CCI

Version

GEN002820-11

Vuln IDs

V-29274

Rule IDs

SV-37718r1_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System AdministratorECAR-1, ECAR-2, ECAR-3

Checks: C-36920r1_chk

Check the system's audit configuration. Procedure: # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -i "removexattr" If "-S removexattr" is not in the result, this is a finding.

Fix: F-32186r1_fix

The "-F arch=<ARCH>" restriction is required on dual-architecture systems (such as x86_64). On dual-architecture systems, two separate rules must exist - one for each architecture supported. Use the generic architectures "b32" and "b64" for specifying these rules. On single architecture systems, the "-F arch=<ARCH>" restriction may be omitted, but if present must match either the architecture of the system or its corresponding generic architecture. The architecture of the system may be determined by running "uname -m". See the auditctl(8) manpage for additional details. Any restrictions (such as with "-F") beyond those provided in the example rules are not in strict compliance with this requirement, and are a finding unless justified and documented appropriately. The use of audit keys consistent with the provided example is encouraged to provide for uniform audit logs, however omitting the audit key or using an alternate audit key is not a finding. Procedure: Edit the audit.rules file and add the following lines to enable auditing of discretionary access control permissions modifications. -a exit,always -F arch=<ARCH> -S removexattr Restart the auditd service. # service auditd restart

b

The audit system must be configured to audit all discretionary access control permission modifications.

AU-2 - Medium - CCI-000126 - V-29275 - SV-37719r1_rule

RMF Control

AU-2

Severity

M

CCI

Version

GEN002820-12

Vuln IDs

V-29275

Rule IDs

SV-37719r1_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System AdministratorECAR-1, ECAR-2, ECAR-3

Checks: C-36921r1_chk

Check the system's audit configuration. Procedure: # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -i "lremovexattr" If "-S lremovexattr" is not in the result, this is a finding.

Fix: F-32187r1_fix

The "-F arch=<ARCH>" restriction is required on dual-architecture systems (such as x86_64). On dual-architecture systems, two separate rules must exist - one for each architecture supported. Use the generic architectures "b32" and "b64" for specifying these rules. On single architecture systems, the "-F arch=<ARCH>" restriction may be omitted, but if present must match either the architecture of the system or its corresponding generic architecture. The architecture of the system may be determined by running "uname -m". See the auditctl(8) manpage for additional details. Any restrictions (such as with "-F") beyond those provided in the example rules are not in strict compliance with this requirement, and are a finding unless justified and documented appropriately. The use of audit keys consistent with the provided example is encouraged to provide for uniform audit logs, however omitting the audit key or using an alternate audit key is not a finding. Procedure: Edit the audit.rules file and add the following lines to enable auditing of discretionary access control permissions modifications. -a exit,always -F arch=<ARCH> -S lremovexattr Restart the auditd service. # service auditd restart

b

The audit system must be configured to audit all discretionary access control permission modifications.

AU-2 - Medium - CCI-000126 - V-29279 - SV-37726r1_rule

RMF Control

AU-2

Severity

M

CCI

Version

GEN002820-13

Vuln IDs

V-29279

Rule IDs

SV-37726r1_rule

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.System AdministratorECAR-1, ECAR-2, ECAR-3

Checks: C-36922r1_chk

Check the system's audit configuration. Procedure: # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -i "fremovexattr" If "-S fremovexattr" is not in the result, this is a finding.

Fix: F-32188r1_fix

The "-F arch=<ARCH>" restriction is required on dual-architecture systems (such as x86_64). On dual-architecture systems, two separate rules must exist - one for each architecture supported. Use the generic architectures "b32" and "b64" for specifying these rules. On single architecture systems, the "-F arch=<ARCH>" restriction may be omitted, but if present must match either the architecture of the system or its corresponding generic architecture. The architecture of the system may be determined by running "uname -m". See the auditctl(8) manpage for additional details. Any restrictions (such as with "-F") beyond those provided in the example rules are not in strict compliance with this requirement, and are a finding unless justified and documented appropriately. The use of audit keys consistent with the provided example is encouraged to provide for uniform audit logs, however omitting the audit key or using an alternate audit key is not a finding. Procedure: Edit the audit.rules file and add the following lines to enable auditing of discretionary access control permissions modifications. -a exit,always -F arch=<ARCH> -S fremovexattr Restart the auditd service. # service auditd restart

b

The audit system must be configured to audit the loading and unloading of dynamic kernel modules - delete_module.

AU-2 - Medium - CCI-000126 - V-29281 - SV-37728r1_rule

RMF Control

AU-2

Severity

M

CCI

Version

GEN002825-2

Vuln IDs

V-29281

Rule IDs

SV-37728r1_rule

Actions concerning dynamic kernel modules must be recorded as they are substantial events. Dynamic kernel modules can increase the attack surface of a system. A malicious kernel module can be used to substantially alter the functioning of a system, often with the purpose of hiding a compromise from the SA.System AdministratorECAR-1, ECAR-2, ECAR-3

Checks: C-36927r1_chk

Determine if the delete_module syscall is audited. # cat /etc/audit/audit.rules | grep -e "-a exit,always" | grep -i "delete_module" If the result does not contain "-S delete_module", this is a finding.

Fix: F-32192r1_fix

The "-F arch=<ARCH>" restriction is required on dual-architecture systems (such as x86_64). On dual-architecture systems, two separate rules must exist - one for each architecture supported. Use the generic architectures "b32" and "b64" for specifying these rules. On single architecture systems, the "-F arch=<ARCH>" restriction may be omitted, but if present must match either the architecture of the system or its corresponding generic architecture. The architecture of the system may be determined by running "uname -m". See the auditctl(8) manpage for additional details. Any restrictions (such as with "-F") beyond those provided in the example rules are not in strict compliance with this requirement, and are a finding unless justified and documented appropriately. The use of audit keys consistent with the provided example is encouraged to provide for uniform audit logs, however omitting the audit key or using an alternate audit key is not a finding. Procedure: Configure auditing of the delete_module syscalls. Add the following to the "etc/audit/audit.rules" or "etc/audit.rules" file: -a exit,always -S delete_module Restart the auditd service. # service auditd restart

b

The audit system must be configured to audit the loading and unloading of dynamic kernel modules - /sbin/insmod.

AU-2 - Medium - CCI-000126 - V-29284 - SV-37734r2_rule

RMF Control

AU-2

Severity

M

CCI

Version

GEN002825-3

Vuln IDs

V-29284

Rule IDs

SV-37734r2_rule

Actions concerning dynamic kernel modules must be recorded as they are substantial events. Dynamic kernel modules can increase the attack surface of a system. A malicious kernel module can be used to substantially alter the functioning of a system, often with the purpose of hiding a compromise from the SA.System Administrator

Checks: C-36932r1_chk

Determine if /sbin/insmod is audited. # cat /etc/audit/audit.rules | grep "/sbin/insmod" If the result does not start with "-w" and contain "-p x", this is a finding.

Fix: F-32197r2_fix

The use of audit keys consistent with the provided example is encouraged to provide for uniform audit logs, however omitting the audit key or using an alternate audit key is not a finding. Procedure: Configure auditing of the /sbin/insmod, files. Add the following to the "etc/audit/audit.rules" or "etc/audit.rules" file: -w /sbin/insmod -p x Restart the auditd service. # service auditd restart

b

The audit system must be configured to audit the loading and unloading of dynamic kernel modules -/sbin/modprobe.

AU-2 - Medium - CCI-000126 - V-29286 - SV-37738r2_rule

RMF Control

AU-2

Severity

M

CCI

Version

GEN002825-4

Vuln IDs

V-29286

Rule IDs

SV-37738r2_rule

Actions concerning dynamic kernel modules must be recorded as they are substantial events. Dynamic kernel modules can increase the attack surface of a system. A malicious kernel module can be used to substantially alter the functioning of a system, often with the purpose of hiding a compromise from the SA.System Administrator

Checks: C-36935r1_chk

Determine if the /sbin/modprobe file is audited. # cat /etc/audit/audit.rules | grep "/sbin/modprobe" If the result does not start with "-w" and contain "-p x", this is a finding.

Fix: F-32199r2_fix

The use of audit keys consistent with the provided example is encouraged to provide for uniform audit logs, however omitting the audit key or using an alternate audit key is not a finding. Procedure: -w /sbin/modprobe -p x Restart the auditd service. # service auditd restart

b

The audit system must be configured to audit the loading and unloading of dynamic kernel modules - /sbin/rmmod

AU-2 - Medium - CCI-000126 - V-29288 - SV-37741r2_rule

RMF Control

AU-2

Severity

M

CCI

Version

GEN002825-5

Vuln IDs

V-29288

Rule IDs

SV-37741r2_rule

Actions concerning dynamic kernel modules must be recorded as they are substantial events. Dynamic kernel modules can increase the attack surface of a system. A malicious kernel module can be used to substantially alter the functioning of a system, often with the purpose of hiding a compromise from the SA.System Administrator

Checks: C-36939r1_chk

Determine if the /sbin/rmmod file is audited. # cat /etc/audit/audit.rules | grep "/sbin/rmmod" If the result does not start with "-w" and contain "-p x", this is a finding.

Fix: F-32203r2_fix

The use of audit keys consistent with the provided example is encouraged to provide for uniform audit logs, however omitting the audit key or using an alternate audit key is not a finding. Procedure: Configure auditing of the /sbin/rmmod file. Add the following to the "etc/audit/audit.rules" or "etc/audit.rules" file: -w /sbin/rmmod -p x Restart the auditd service. # service auditd restart

b

Files in cron script directories must have mode 0700 or less permissive.

AC-6 - Medium - CCI-000225 - V-29289 - SV-37745r1_rule

RMF Control

AC-6

Severity

M

CCI

Version

GEN003080-2

Vuln IDs

V-29289

Rule IDs

SV-37745r1_rule

To protect the integrity of scheduled system jobs and prevent malicious modification to these jobs, crontab files must be secured.System AdministratorECLP-1

Checks: C-36943r1_chk

Check the mode of scripts in cron job directories. # ls -lL /etc/cron.daily/ # ls -lL /etc/cron.hourly/ # ls -lL /etc/cron.monthly/ # ls -lL /etc/cron.weekly/ If any cron script has a mode more permissive than 0700, this is a finding.

Fix: F-32208r1_fix

Change the mode of the cron scripts. # chmod 0700 /etc/cron.daily/* /etc/cron.hourly/* /etc/cron.monthly/* /etc/cron.weekly/*

b

The system must not have the unnecessary "games" account.

AC-2 - Medium - CCI-000012 - V-29376 - SV-38177r1_rule

RMF Control

AC-2

Severity

M

CCI