AIX 6.1 SECURITY TECHNICAL IMPLEMENTATION GUIDE
V1R14 | 2018-09-18 | U_AIX_6.1_STIG_V1R14_Manual-xccdf.xml | |
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V1R8 | 2016-06-01 | U_AIX_6-1_V1R8_Manual-xccdf.xml | |
The AIX Security Technical Implementation Guide (STIG) is published as a tool to improve the security of Department of Defense (DoD) information systems. Comments or proposed revisions to this document should be sent via email to the following address: [email protected] |
Comparison |
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All 512 |
No Change 489 |
Updated 16 |
Added 1 |
Removed 6 |
V-756
No Change
Findings ID: | GEN000020 | Rule ID: | SV-27039r1_rule | Severity: | medium | CCI: | CCI-000213 |
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Discussion
If the system does not require a valid root password 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 AdministratorIAIA-1, IAIA-2Checks
Ensure the root account for any bootable partitions has a password assigned in the /etc/security/passwd file.Fix
Assign a root account password for any bootable partition.
V-760
No Change
Findings ID: | GEN000280 | Rule ID: | SV-38668r1_rule | Severity: | medium | CCI: | CCI-000770 |
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Discussion
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.System AdministratorIAIA-1Checks
Use the last command to check for multiple accesses to an account from different workstations/IP addresses. If users log directly onto accounts, rather than using the su command from their own named account to access them, this is a finding (such as logging directly on to Oracle). Also, ask the SA or the IAO if shared accounts are logged into directly or if users log on to an individual account and switch user to the shared account.# last <unix account>
Shared or Application accounts can have direct login disabled by setting the rlogin parameter to false in the users stanza of the /etc/security/user file.
#lsuser -a rlogin < user_id >
If users log directly on to shared accounts, this is a finding.
Fix
Use the switch user (su) command from a named account login to access shared accounts. Maintain audit trails to identify the actual user of that account name. Document requirements and procedures for users/administrators to log into their own accounts first and then switch user (su) to the account that must be shared.Direct login to shared or application accounts can be prevented by setting the rlogin = false in the accounts stanza of the /etc/security/user file. Additional hardening of the shared/application accounts can be done with the sugroups = in the accounts stanza of the /etc/security/user file.
#chuser rlogin=false < user id >
V-761
No Change
Findings ID: | GEN000300 | Rule ID: | SV-27064r1_rule | Severity: | medium | CCI: | CCI-000764 |
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Discussion
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-2Checks
Perform the following to ensure there are no duplicate account names:# usrck -n ALL
If any duplicate account names are found, this is a finding.
Fix
Change user account names, or delete accounts, so each account has a unique name.
V-762
No Change
Findings ID: | GEN000320 | Rule ID: | SV-27067r1_rule | Severity: | medium | CCI: | CCI-000764 |
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Discussion
Accounts that share 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-2Checks
Perform the following to ensure there are no duplicate UIDs:# usrck -n ALL
If any duplicate UIDs are found, this is a finding.
Fix
Edit user accounts to provide unique UIDs for each account.
V-763
No Change
Findings ID: | GEN000400 | Rule ID: | SV-38932r1_rule | Severity: | medium | CCI: | CCI-000048 |
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Discussion
Failure to display the login banner prior to a logon attempt will negate legal proceedings resulting from unauthorized access to system resources.System AdministratorECWM-1Checks
Access the system console and make a logon 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
Edit /etc/security/login.cfg and assign the herald value for the default and /dev/console stanzas to one of the DoD login banners (based on the character limitations imposed by the system).# chsec -f /etc/security/login.cfg -s default -a herald="<DoD Login Banner>"
OR
# vi /etc/security/login.cfg and add a herald = <DoD Login Banner> statement to the default stanza
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."
V-765
No Change
Findings ID: | GEN000440 | Rule ID: | SV-38935r1_rule | Severity: | medium | CCI: | CCI-000126 |
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Discussion
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-3Checks
Determine if successful logons are being logged.# last | more
Determine if unsuccessful logons are being logged.
# last -f /etc/security/failedlogin | more
If the commands do not return successful and unsuccessful logins, this is a finding.
Fix
Edit /etc/syslog.conf and add local log destinations for auth.* or both auth.notice and auth.info."auth.info /var/log/authlog"
Verify service startup scripts for syslog and utmp (if present) are enabled.
# vi /etc/rc.tcpip
Check the syslogd service is not commented out.
Refresh syslogd.
#refresh -s syslogd
V-766
No Change
Findings ID: | GEN000460 | Rule ID: | SV-38671r1_rule | Severity: | medium | CCI: | CCI-000044 |
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Discussion
Disabling accounts after a limited number of unsuccessful login attempts improves protection against password guessing attacks.System AdministratorECLO-1, ECLO-2Checks
# /usr/sbin/lsuser -a loginretries ALL | moreCheck all active accounts on the system for the maximum number of tries before the system will lock the account. If a user has values set to 0 or greater then 3, this is a finding.
Fix
Use the chsec command to configure the number of unsuccessful logins resulting in account lockout.# chsec -f /etc/security/user -s default -a loginretries=3
# chsec -f /etc/security/user -s <user id> -a loginretries=3
V-768
No Change
Findings ID: | GEN000480 | Rule ID: | SV-38839r1_rule | Severity: | medium | CCI: | CCI-000043 |
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Discussion
Enforcing a delay between successive failed login attempts increases protection against automated password guessing attacks.System AdministratorECLO-1, ECLO-2Checks
Check the logindelay parameter.# more /etc/security/login.cfg
OR
#grep logindelay /etc/security/login.cfg | grep -v \*
Verify the value of the logindelay variable is 4 or more in each stanza. If the value of logindelay is not 4 or more, this is a finding.
Fix
Use vi or the chsec command to change the login delay time period.#chsec -f /etc/security/login.cfg -s default -a logindelay=4
OR
# vi /etc/security/login.cfg
Add logindelay = 4 to the default stanza.
V-769
No Change
Findings ID: | GEN000520 | Rule ID: | SV-769r2_rule | Severity: | medium | CCI: | CCI-000225 |
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Discussion
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-1Checks
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. Execute the following to determine which user owns the process(es) associated with the application. If the owner is root, this is a finding.# ps -ef | more
Fix
Configure the system so the owner of a session requiring 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. 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.
V-770
No Change
Findings ID: | GEN000560 | Rule ID: | SV-27107r1_rule | Severity: | high | CCI: | CCI-000366 |
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Discussion
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-2Checks
Fix
Remove or configure a password for any account with a blank password.# passwd <user id>
# smitty passwd
To remove an account with a blank password.
# smitty rmuser
V-773
No Change
Findings ID: | GEN000880 | Rule ID: | SV-773r2_rule | Severity: | medium | CCI: | CCI-000366 |
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Discussion
If an account has an UID of 0, it has root authority. Multiple accounts with an UID of 0 afford more opportunity for potential intruders to guess a password for a privileged account.System AdministratorECLP-1Checks
Check the system for duplicate UID 0 assignments by listing all accounts assigned UID 0.Procedure:
# grep ":0:" /etc/passwd | awk -F":" '{print$1":"$3":"}' | grep ":0:"
If any accounts other than root are assigned UID 0, this is a finding.
Fix
Remove or change the UID of accounts other than root that have UID 0.
V-774
No Change
Findings ID: | GEN000900 | Rule ID: | SV-38940r1_rule | Severity: | low | CCI: | CCI-000366 |
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Discussion
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 that root places in its default directory. It also gives root the same discretionary access control for root's home directory as for the other plain user home directories.System AdministratorECCD-1, ECCD-2Checks
Fix
The root home directory should be something other than / (such as /root).Procedure:
# mkdir /root
# chown root /root
# chgrp sys /root
# chmod 700 /root
# cp -r /.??* /root/.
Then, edit the passwd file and change the root home directory to /root. The cp -r /.??* command copies all files and subdirectories of file names that begin with "." into the new root directory, which preserves the previous root environment. Must be in the "/" directory when executing the "cp" command.
V-775
No Change
Findings ID: | GEN000920 | Rule ID: | SV-38941r1_rule | Severity: | medium | CCI: | CCI-000225 |
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Discussion
Permissions greater than 0700 could allow unauthorized users access to the root home directory.System AdministratorECCD-1, ECCD-2Checks
Check the mode of the root home directory.Procedure:
# grep "^root" /etc/passwd | awk -F":" '{print $6}'
# ls -ld <root home directory>
If the mode of the directory is not equal to 0700, this is a finding. If the home directory is /, this is not applicable.
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 /root.
V-776
Updated
Findings ID: | GEN000940 | Rule ID: | SV-40085r |
Severity: | medium | CCI: | CCI-000366 |
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Discussion
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 colonChecks
To view the root user's PATH, log in as the root user, and execute the following.# 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
If directories beyond those in the vendor's default root path are present
Fix
Edit the root user's local initialization filesEdit the root user’s local initialization files a demove any empty entrt y th ts sedifen.
# cd <root's home directory>
# vi .profile .cshrc
If the bash shell is installed, edit these additional files.
# vi .bashrc .bash_profile
V-777
No Change
Findings ID: | GEN000960 | Rule ID: | SV-777r2_rule | Severity: | medium | CCI: | CCI-000366 |
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Discussion
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
Fix
For each world-writable path in root's executable search path, perform 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.
V-778
No Change
Findings ID: | GEN000980 | Rule ID: | SV-38683r1_rule | Severity: | medium | CCI: | CCI-000770 |
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Discussion
Limiting the root account direct logins to only system consoles protects the root account from direct unauthorized access from a non-console device.System AdministratorECPA-1Checks
Check the remote login ability of the root account.Procedure:
# lsuser -a rlogin root
If the rlogin value is not false, this is a finding.
Fix
The root account can be protected from non-console device logins by setting rlogin = false in the root: stanza of the /etc/security/user file.#chsec -f /etc/security/user -s root -a rlogin=false
V-780
No Change
Findings ID: | GEN000360 | Rule ID: | SV-39094r1_rule | Severity: | medium | CCI: | CCI-000366 |
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Discussion
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-1Checks
# more /etc/passwdConfirm all accounts with a GID of 99 and below (499 and below for Linux) are used by a system account.
If a GID reserved for system accounts, 0 - 99 (0 - 499 for Linux), is used by a non-system account, this is a finding.
Fix
Change the primary group GID numbers for non-system accounts with reserved primary group GIDs (those less or equal to 99 in general, or 499 for Linux).# smitty chuser
V-781
No Change
Findings ID: | GEN000380 | Rule ID: | SV-27071r1_rule | Severity: | low | CCI: | CCI-000366 |
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Discussion
If a user is assigned the GID of a group that does not exist on the system, and a group with that GID is subsequently created, the user may have unintended rights to the group.System AdministratorECSC-1
Checks
Perform the following to ensure there are no GIDs referenced in /etc/passwd not defined in /etc/group:# usrck -n ALL
If GIDs referenced in /etc/passwd are not defined in /etc/group are returned, this is a finding.
Fix
Add a group to the system for each GID referenced without a corresponding group.# smitty mkgroup
V-782
No Change
Findings ID: | GEN006480 | Rule ID: | SV-41526r2_rule | Severity: | medium | CCI: | CCI-001259 |
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Discussion
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 AdministratorECID-1Checks
Ask the SA or IAO if a host-based intrusion detection application is loaded on the system.Determine if the application is loaded on the system.
Procedure:
# find / -name <daemon name> -print
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
Install a host-based intrusion detection tool.
V-783
No Change
Findings ID: | GEN000120 | Rule ID: | SV-27060r2_rule | Severity: | medium | CCI: | CCI-001227 |
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Discussion
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 AdministratorChecks
Obtain the list of available security patches from IBM.Verify the available patches and service packs have been installed on the system.
Check the currently running TL (Technology Levels and Service Packs).
#oslevel -s
Perform the following to obtain a list of installed patches.
# /usr/sbin/instfix -i
If there are security patches available and applicable for the system that have not been installed, this is a finding.
Fix
Use a web browser to access the vendor's support web site. Download the service packs and patches. Use SMIT to apply the updates.#smitty update_all
V-784
No Change
Findings ID: | GEN001140 | Rule ID: | SV-784r2_rule | Severity: | medium | CCI: | CCI-000225 |
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Discussion
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-2Checks
Check system directories for uneven file permissions.Procedure:
# ls -lL /etc /bin /usr/bin /usr/lbin /usr/ucb /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
Change the mode of files with uneven permissions so owners do not have less permission than group or world users.
V-785
No Change
Findings ID: | GEN001160 | Rule ID: | SV-38942r1_rule | Severity: | medium | CCI: | CCI-000366 |
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Discussion
Unowned files and directories may be unintentionally inherited if a user is assigned the same UID as the UID of the unowned files.System AdministratorECCD-1, ECCD-2Checks
Check the system for files with no assigned owner.Procedure:
# find / -nouser -print
If any files have no assigned owner, this is a finding.
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.#chown <a-valid-user> <directory>/<file>
V-786
No Change
Findings ID: | GEN001180 | Rule ID: | SV-38774r1_rule | Severity: | medium | CCI: | CCI-000225 |
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Discussion
Restricting permission on daemons will protect them from unauthorized modification and possible system compromise.System AdministratorECLP-1Checks
Check the mode of network services daemons.# ls -la /usr/sbin /usr/bin
If the mode of a network services daemon is more permissive than 0755, this is a finding.
NOTE: Network daemons that may not reside in these directories (such as httpd or sshd) must also be checked for the correct permissions.
Fix
Change the mode of the network services daemon.# chmod 0755 <path>
V-787
No Change
Findings ID: | GEN001260 | Rule ID: | SV-787r2_rule | Severity: | medium | CCI: | CCI-001314 |
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Discussion
If the system log files are not protected, unauthorized users could change the logged data, eliminating its forensic value.System AdministratorECTP-1Checks
Check the mode of log files.Procedure:
# ls -lL /var/log /var/log/syslog /var/adm
If any of the log files have modes more permissive than 0640, this is a finding.
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. Any subsystems that require less stringent permissions must be documented.
V-788
No Change
Findings ID: | GEN001800 | Rule ID: | SV-38735r1_rule | Severity: | medium | CCI: | CCI-000225 |
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Discussion
If the skeleton files are not protected, unauthorized personnel could change user startup parameters and possibly jeopardize user files.System AdministratorECLP-1
Checks
Check skeleton files permissions.Procedure:
# ls -l /etc/security/.profile
If a skeleton file has a mode more permissive than 0644, this is a finding.
Check the mkuser.sys file. The /etc/security/mkuser.sys is a script containing items used in creation of users' ~/.profile files. This script needs to be both protected from unauthorized modification, but also needs to be executable, therefore the permissions need to be at the mode of 755.
#ls -l /etc/security/mkuser.sys
If the mkuser.sys file has a mode more permissive than 0755, this is a finding.
Fix
Change the mode of skeleton files with incorrect mode.# chmod 0644 /etc/security/.profile
#chmod 0755 /etc/security/mkuser.sys
V-789
No Change
Findings ID: | GEN001320 | Rule ID: | SV-38775r1_rule | Severity: | medium | CCI: | CCI-000225 |
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Discussion
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 AdministratorECLP-1Checks
Perform the following to check NIS file ownership.# ls -lRa /var/nis /var/yp /usr/lib/nis /usr/lib/netsvc/yp
If the file ownership is not root, sys, or bin, this is a finding.
Fix
Change the owner of the NIS files to root, sys, or bin.Procedure (example):
# chown root < directory>/< file >
V-790
No Change
Findings ID: | GEN001340 | Rule ID: | SV-38776r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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 AdministratorECLP-1Checks
Check the group ownership of the NIS files.Procedure:
# ls -lRa /var/nis /var/yp /usr/lib/nis /usr/lib/netsvc/yp
If the file group owner is not sys, bin, or system, this is a finding.
Fix
Change the group owner of the NIS files to sys, bin, system, or other.Procedure:
# chgrp system < directory>/< file >
V-791
No Change
Findings ID: | GEN001360 | Rule ID: | SV-38781r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
NIS/NIS+/yp files are part of the system's identification and authentication processes and are, therefore, critical to system security. Unauthorized modification of these files could compromise these processes and the system.System AdministratorECLP-1Checks
Perform the following to check NIS file mode# ls -lRa /var/nis /var/yp /usr/lib/nis /usr/lib/netsvc/yp
If the file's mode is more permissive than 0755, this is a finding.
Fix
Change the mode of NIS/NIS+/yp files to 0755 or less permissive.Procedure (example):
# chmod 0755 <filename>
V-792
No Change
Findings ID: | GEN001280 | Rule ID: | SV-792r2_rule | Severity: | low | CCI: | CCI-000225 |
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Discussion
If manual pages are compromised, misleading information could be inserted, causing actions that may compromise the system.System AdministratorECCD-1, ECCD-2Checks
Check the mode of the manual page files.Procedure:
# ls -lLR /usr/share/man /usr/share/info /usr/share/infopage
If any of the manual page files have a mode more permissive than 0644, this is a finding.
Fix
Change the mode of manual page files to 0644 or less permissive.Procedure (example):
# chmod 0644 <path>/<manpage>
V-793
No Change
Findings ID: | GEN001300 | Rule ID: | SV-38943r1_rule | Severity: | medium | CCI: | CCI-001499 |
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Discussion
Unauthorized access could destroy the integrity of the library files.System AdministratorDCSL-1Checks
Check the mode of library files.Procedure:
# ls -lLR /usr/lib /lib
If any of the library files have a mode more permissive than 0755, this is a finding.
Fix
Change the mode of library files to 0755 or less permissive.Procedure (example):
# chmod 0755 <path>/<library-file>
NOTE: Library files should have an extension of .a or .so (a=archive, so=shared object) extension, possibly followed by a version.
V-794
No Change
Findings ID: | GEN001200 | Rule ID: | SV-794r4_rule | Severity: | medium | CCI: | CCI-001499 |
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Discussion
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 is world-writable.System AdministratorChecks
Check the permissions for files in /etc, /bin, /usr/bin, /usr/lbin, /usr/ucb, /sbin, and /usr/sbin.Procedure:
# ls -lL /etc /bin /usr/bin /usr/lbin /usr/ucb /sbin /usr/sbin
If any command file is listed and has a mode more permissive than 755, this is a finding.
Note: Elevate to Severity Code I if any command file listed is world-writable.
Fix
Change the mode for system command files to 755 or less permissive.Procedure:
# chmod 755 <filename>
V-795
No Change
Findings ID: | GEN001220 | Rule ID: | SV-40783r1_rule | Severity: | medium | CCI: | CCI-001499 |
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Discussion
Restricting permissions will protect the files from unauthorized modification.System AdministratorECLP-1Checks
Check the ownership of system files, programs, and directories.Procedure:
# ls -lLa /etc /bin /usr/bin /usr/lbin /usr/ucb /sbin /usr/sbin
If any of the system files, programs, or directories are not owned by a system account, this is a finding. For this check, the system-provided "ipsec" user is considered to be a system account.
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.)
V-796
No Change
Findings ID: | GEN001240 | Rule ID: | SV-39098r1_rule | Severity: | medium | CCI: | CCI-001499 |
---|
Discussion
Restricting permissions will protect the files from unauthorized modification.System AdministratorECLP-1Checks
Check the group ownership of system files, programs, and directories.Procedure:
# ls -lLa /etc /bin /usr/bin /usr/lbin /usr/ucb /sbin /usr/sbin
If any system file, program, or directory is not group-owned by a system group, this is a finding. For this check, the system-provided "ipsec" group is also acceptable.
Fix
Change the group owner of system files to a system group.Procedure:
# chgrp sys /path/to/system/file (System groups other than sys may be used.)
V-797
No Change
Findings ID: | GEN001400 | Rule ID: | SV-38944r1_rule | Severity: | medium | CCI: | CCI-000225 |
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Discussion
The /etc/security/passwd 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-1Checks
Check the ownership of the /etc/security/passwd file.Procedure:
# ls -lL /etc/security/passwd
If the owner of this file is not root, this is a finding.
Fix
Change the ownership of the /etc/security/passwd file.# chown root /etc/security/passwd
V-798
No Change
Findings ID: | GEN001380 | Rule ID: | SV-798r2_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
If the password file is writable by a group owner or the world, the risk of password file compromise is increased. The password file contains the list of accounts on the system and associated information.System AdministratorECLP-1Checks
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
Change the mode of the passwd file to 0644.Procedure:
# chmod 0644 /etc/passwd
Document all changes.
V-800
No Change
Findings ID: | GEN001420 | Rule ID: | SV-38728r1_rule | Severity: | medium | CCI: | CCI-000225 |
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Discussion
The /etc/security/passwd 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-1Checks
Check the mode of the /etc/security/passwd file.Procedure:
# ls -lL /etc/security/passwd
If the mode of this file is more permissive than 0400, this is a finding.
Fix
Change the mode of the /etc/security/passwd file.# chmod 0400 /etc/security/passwd
V-801
No Change
Findings ID: | GEN002380 | Rule ID: | SV-801r2_rule | Severity: | medium | CCI: | CCI-000368 |
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Discussion
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 that allow reading and writing of files, or shell escapes. Only default vendor-supplied executables should have the setuid bit set.trueSystem AdministratorInformation Assurance OfficerECPA-1Checks
Files with the setuid bit set will allow anyone running these files to be temporarily assigned the user or group ID of the file. If an executable with setuid allows shell escapes, the user can operate on the system with the effective permission rights of the user or group owner.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 IAO if files with the setuid bit set have been documented. If any undocumented file has its setuid bit set, this is a finding.
Fix
Document the files with the setuid bit set or unset the setuid bit on the executable.
V-802
No Change
Findings ID: | GEN002440 | Rule ID: | SV-38945r1_rule | Severity: | medium | CCI: | CCI-000368 |
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Discussion
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 that allow reading and writing of files, or shell escapes.trueInformation Assurance OfficerSystem AdministratorECPA-1Checks
Locate all setgid files on the system.Procedure:
# find / -perm -2000
If the ownership, permissions, location, and ACLs of all files with the setgid bit set are not documented, this is a finding.
Fix
All files with the sgid bit set will be documented in the system baseline and authorized by the Information Systems Security Officer. Locate all sgid files with the following command:#find / -perm -2000 -exec ls -lL {} \;
# find / -perm -2000 -exec aclget {} \;
Ensure sgid files are part of the operating system software, documented application software, documented utility software, or documented locally developed software. Ensure none are text files or shell programs.
V-803
No Change
Findings ID: | GEN002400 | Rule ID: | SV-803r2_rule | Severity: | medium | CCI: | CCI-000318 |
---|
Discussion
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 that allow reading and writing of files, or shell escapes.System AdministratorDCSL-1Checks
Determine if a weekly automated or manual process is 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.Fix
Establish a weekly automated or manual process to generate a list of setuid files on the system and compare it with the prior list. To create a list of setuid files use the following command.# find / -perm -4000 > setuid-file-list
V-804
No Change
Findings ID: | GEN002460 | Rule ID: | SV-804r2_rule | Severity: | medium | CCI: | CCI-000318 |
---|
Discussion
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 that allow reading and writing of files, or shell escapes.System AdministratorDCSL-1Checks
Determine 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.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 use the following command.# find / -perm -2000 > setgid-file-list
V-805
No Change
Findings ID: | GEN002420 | Rule ID: | SV-38746r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check /etc/filesystems 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.Each file system stanza must contain a device special file and may additionally contain all of the following fields
type = , options = , and check = .
# more /etc/filesystems
# lsfs
If any of these files systems do not mount with the nosuid option, it is a finding.
Fix
Edit /etc/filesystems and add the options = nosuid to the stanza of file system mounted from removable media or network shares, and any file system not containing approved setuid or setgid files.OR
Add the nosuid option with the chfs command.
# chfs -a options=nosuid <filesystem>
V-806
No Change
Findings ID: | GEN002500 | Rule ID: | SV-806r2_rule | Severity: | low | CCI: | CCI-000366 |
---|
Discussion
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
Verify 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
Set the sticky bit on all public directories.Procedure:
# chmod 1777 /tmp
(Replace /tmp with the public directory missing the sticky bit, if necessary.)
V-807
No Change
Findings ID: | GEN002520 | Rule ID: | SV-807r2_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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
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
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.)
V-808
No Change
Findings ID: | GEN002560 | Rule ID: | SV-39501r1_rule | Severity: | medium | CCI: | CCI-000366 |
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Discussion
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-2Checks
Check global initialization files for the configured umask value.Procedure:
# grep umask /etc/*
Check local initialization files for the configured umask value.
Procedure:
# grep umask /userhomedirectory/.*
If the system and user default umask is not 077, this is a finding.
NOTE: If the default umask is 000 or allows for the creation of world-writable files, this becomes a Severity Code I (CAT I) finding.
Fix
Edit local and global initialization files that contain "umask" and change them to use 077 instead of the current value.
V-810
No Change
Findings ID: | GEN002640 | Rule ID: | SV-38897r1_rule | Severity: | medium | CCI: | CCI-000178 |
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Discussion
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-1Checks
Determine if default system accounts (such as those for guest, sys, bin, uucp, nuucp, daemon, smtp, and lpd) have been disabled.Procedure:
# lsuser -a account_locked ALL
If there are any unlocked default system accounts, this is a finding.
Fix
Lock the default system account(s).# chuser account_locked=true <user>
V-811
No Change
Findings ID: | GEN002660 | Rule ID: | SV-38946r1_rule | Severity: | medium | CCI: | CCI-000169 |
---|
Discussion
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-3Checks
Determine if auditing is enabled.# /usr/sbin/audit query | head -1
If the response Auditing On is not returned, this is a finding.
Fix
Use SMIT or command line to enable auditing on the system.#audit start
Additionally, make sure auditing subsystem starts on system startup.
#mkitab -i cron "audit:2:once:/usr/sbin/audit start 2>&1 >
/dev/console"
V-812
No Change
Findings ID: | GEN002680 | Rule ID: | SV-38900r1_rule | Severity: | medium | CCI: | CCI-000162 |
---|
Discussion
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-1Checks
Perform the following to determine the location of audit logs and then check the ownership.Procedure:
# grep -p bin: /etc/security/audit/config
Directories to search will be listed under the bin stanza.
# ls -la <audit directories>
If any audit log file is not owned by root, this is a finding.
Fix
Change the ownership of the audit log file(s).Procedure:
# chown root <audit log file>
V-813
No Change
Findings ID: | GEN002700 | Rule ID: | SV-38904r1_rule | Severity: | medium | CCI: | CCI-000163 |
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Discussion
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-1Checks
Perform the following to determine the location of audit logs and then check the mode of the files.Procedure:
# grep -p bin: /etc/security/audit/config
Directories to search will be listed under the bin stanza.
# ls -la <audit directories>
If any audit log file has a mode more permissive than 0640, this is a finding.
Fix
Change the mode of the audit log directories/files.# chmod 0750 <audit directory>
# chmod 0640 <audit file>
V-814
No Change
Findings ID: | GEN002720 | Rule ID: | SV-38850r1_rule | Severity: | medium | CCI: | CCI-000126 |
---|
Discussion
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-3Checks
Check the system audit configuration to determine if failed attempts to access files and programs are audited.Check system activities (events) to audit are listed in the /etc/security/audit/events file.
Procedure:
# more /etc/security/audit/events
If the FILE_Open event is not configured, this is a finding.
Check the FILE_Open audit event is defined in the audit classes' stanza classes: of the /etc/security/audit/config file.
Procedure:
#more /etc/security/audit/config
Make note of the audit class(es) that the FILE_Open event is associated with.
If the FILE_Open event is not associated with any audit classes in the classes: stanza, this is a finding.
Verify the audit class is associated with the default user and all other user ids listed in the users: stanza of the /etc/security/audit/config file.
Procedure:
#more /etc/security/audit/config
If the class(es) the FILE_Open event is(/are) not associated with the default user and all the system users in the users: stanza, this is a finding.
Supplementary Information:
Successful setup of AIX auditing requires several files and stanza's to be correctly configured.
1. The /etc/security/audit/events must have the system call defined.
2. The /etc/security/audit/config has 2 stanzas that need to be configured
a. "classes:" stanza. Each entry in this stanza defines two things. The first is the name of a class to group the events to be audited on. The class is linked to users of the system for auditing. The second is the event(s) to be audited in this class: stanza.
Example:
classes:
DISA_CLASS = FILE_Open, File_Unlink, FS_Rmdir
b. "users:" stanza. There are two options of specifying what users audit on. The first is to explicitly spell out user names.
EXAMPLE:
users:
root = DISA_CLASS
The second is to specify a default catching all users not listed elsewhere in the users: stanza
EXAMPLE
users:
root = DISA_CLASS
default = DISA_CLASS
3. An approach to setup auditing to meet STIG requirements would be to create class stanza with all audit events that are required. The users: stanza would then be populated with the root user, any other user ids with special requirements and finally a default user.
4. The /usr/lib/security/mkuser.default file can have under the users: stanza an entry
auditclasses = class(es) of events to be audited for each new user added to the system.
Fix
Edit /etc/security/audit/events and add the FILE_Open event to the list of audited events.Edit /etc/security/audit/config and add the FILE_Open audit event to an audit class in the classes: stanza.
Edit the /etc/security/audit/config and assign the audit classes that have the FILE_Open event to the users listed in the users: stanza.
V-815
No Change
Findings ID: | GEN002740 | Rule ID: | SV-27294r1_rule | Severity: | medium | CCI: | CCI-000126 |
---|
Discussion
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
Check the system audit configuration to determine if failed attempts to access files and programs are audited.# more /etc/security/audit/events
If auditing of the FILE_Unlink or FS_Rmdir events is not configured, this is a finding.
If no results are returned, this is a finding.
Check the FILE_Unlink and FS_Rmdir audit event(s) are defined in the audit classes' stanza classes: of the /etc/security/audit/config file.
#more /etc/security/audit/config
Make note of the audit class(es) that the File_Unlink and FS_Rmdir events are associated with.
If the FILE_Unlink and FS_Rmdir events are not associated with any audit classes in the classes: stanza this is a finding.
Verify the audit class is associated with the default user and all other user ids listed in the users: stanza of the /etc/security/audit/config file.
#more /etc/security/audit/config
If the class(es) that the FILE_Unlink and FS_Rmdir events are not associated with the default user and all the system users in the users: stanza, this is a finding.
Fix
Edit /etc/security/audit/events and add the FILE_Unlink or FS_Rmdir events to the list of audited events.Edit /etc/security/audit/config and add the FILE_Unlink and FS_Rmdir audit events to an audit class in the classes: stanza.
Edit the /etc/security/audit/config and assign the audit classes containing the FILE_Unlink and FS_Rmdir events to the all users listed in the users: stanza.
V-816
No Change
Findings ID: | GEN002760 | Rule ID: | SV-40138r1_rule | Severity: | medium | CCI: | CCI-000347 |
---|
Discussion
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-3Checks
Check the auditing configuration of the system.# more /etc/security/audit/events
Verify the following events are configured.
ACCT_Disable, ACCT_Enable, AUD_it, BACKUP_Export, DEV_Change, DEV_Configure, DEV_Create, FILE_Chpriv, FILE_Fchpriv, FILE_Mknod, FILE_Owner, FS_Chroot, FS_Mount, FS_Umount, PASSWORD_Check, PROC_Adjtime, PROC_Kill, PROC_Privilege, PROC_Setpgid, PROC_SetUserIDs, RESTORE_Import, TCBCK_Delete, USER_Change, USER_Create, USER_Reboot, USER_Remove, and USER_SetEnv
If any of these events are missing from the configuration, this is a finding.
Check the ACCT_Disable, ACCT_Enable, AUD_it, BACKUP_Export, DEV_Change, DEV_Configure, DEV_Create, FILE_Chpriv, FILE_Fchpriv, FILE_Mknod, FILE_Owner, FS_Chroot, FS_Mount, FS_Umount, PASSWORD_Check, PROC_Adjtime, PROC_Kill, PROC_Privilege, PROC_Setpgid, PROC_SetUserIDs, RESTORE_Import, TCBCK_Delete, USER_Change, USER_Create, USER_Reboot, USER_Remove, and USER_SetEnv audit events are defined in the audit classes' stanza 'classes:' of the /etc/security/audit/config file.
#more /etc/security/audit/config
Make note of the audit class(es) that the ACCT_Disable, ACCT_Enable, AUD_it, BACKUP_Export, DEV_Change, DEV_Configure, DEV_Create, FILE_Chpriv, FILE_Fchpriv, FILE_Mknod, FILE_Owner, FS_Chroot, FS_Mount, FS_Umount, PASSWORD_Check, PROC_Adjtime, PROC_Kill, PROC_Privilege, PROC_Setpgid, PROC_SetUserIDs, RESTORE_Import, TCBCK_Delete, USER_Change, USER_Create, USER_Reboot, USER_Remove, and USER_SetEnv events are associated with.
If the ACCT_Disable, ACCT_Enable, AUD_it, BACKUP_Export, DEV_Change, DEV_Configure, DEV_Create, FILE_Chpriv, FILE_Fchpriv, FILE_Mknod, FILE_Owner, FS_Chroot, FS_Mount, FS_Umount, PASSWORD_Check, PROC_Adjtime, PROC_Kill, PROC_Privilege, PROC_Setpgid, PROC_SetUserIDs, RESTORE_Import, TCBCK_Delete, USER_Change, USER_Create, USER_Reboot, USER_Remove, and USER_SetEnv events are not associated with any audit classes in the classes: stanza, this is a finding.
Verify the audit class is associated with the default user and all other user ids listed in the users: stanza of the /etc/security/audit/config file.
#more /etc/security/audit/config
If the class(es) that the ACCT_Disable, ACCT_Enable, AUD_it, BACKUP_Export, DEV_Change, DEV_Configure, DEV_Create, FILE_Chpriv, FILE_Fchpriv, FILE_Mknod, FILE_Owner, FS_Chroot, FS_Mount, FS_Umount, PASSWORD_Check, PROC_Adjtime,PROC_Kill, PROC_Privilege, PROC_Setpgid, PROC_SetUserIds, RESTORE_Import, TCBCK_Delete, USER_Change, USER_Create, USER_Reboot, USER_Remove, and USER_SetEnv events are not associated with the default user and all the system users in the 'users:' stanza, this is a finding.
Fix
Edit /etc/security/audit/events and add the following events to the list of audited events:ACCT_Disable, ACCT_Enable, AUD_it, BACKUP_Export, DEV_Change, DEV_Configure, DEV_Create, FILE_Chpriv, FILE_Fchpriv, FILE_Mknod, FILE_Owner, FS_Chroot, FS_Mount, FS_Umount, PASSWORD_Check, PROC_Adjtime, PROC_Kill, PROC_Privilege, PROC_Setpgid, PROC_SetUserIDs, RESTORE_Import, TCBCK_Delete, USER_Change, USER_Create, USER_Reboot, USER_Remove, and USER_SetEnv.
Edit /etc/security/audit/config and add the ACCT_Disable, ACCT_Enable, AUD_it, BACKUP_Export, DEV_Change, DEV_Configure, DEV_Create, FILE_Chpriv, FILE_Fchpriv, FILE_Mknod, FILE_Owner, FS_Chroot, FS_Mount, FS_Umount, PASSWORD_Check, PROC_Adjtime, PROC_Kill, PROC_Privilege, PROC_Setpgid, PROC_SetUserIDs, RESTORE_Import, TCBCK_Delete, USER_Change, USER_Create, USER_Reboot, USER_Remove, and USER_SetEnv audit events to an audit class in the classes: stanza.
Edit the /etc/security/audit/config and assign the audit classes with the ACCT_Disable, ACCT_Enable, AUD_it, BACKUP_Export, DEV_Change, DEV_Configure, DEV_Create, FILE_Chpriv, FILE_Fchpriv, FILE_Mknod, FILE_Owner, FS_Chroot, FS_Mount, FS_Umount, PASSWORD_Check, PROC_Adjtime, PROC_Kill, PROC_Privilege, PROC_Setpgid, PROC_SetUserIDs, RESTORE_Import, TCBCK_Delete, USER_Change, USER_Create, USER_Reboot, USER_Remove, and USER_SetEnv events to the all users listed in the users: stanza.
V-818
No Change
Findings ID: | GEN002800 | Rule ID: | SV-38856r1_rule | Severity: | medium | CCI: | CCI-000126 |
---|
Discussion
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-3Checks
Check the system's audit configuration.# more /etc/security/audit/events
Confirm the following events are configured:
USER_Login, USER_Logout, INIT_Start, INIT_End and USER_SU.
If any of these events are not present, this is a finding.
Check the USER_Login, USER_Logout, INIT_Start, INIT_End, and USER_SU audit events are defined in the audit classes' stanza 'classes:' of the /etc/security/audit/config file.
#more /etc/security/audit/config
Make note of the audit class(es) the USER_Login, USER_Logout, INIT_Start, INIT_End, and USER_SU events are associated with.
If the USER_Login, USER_Logout, INIT_Start, INIT_End, and USER_SU events are not associated with any audit classes in the classes: stanza, this is a finding.
Verify the audit class is associated with the default user and all other user ids listed in the users: stanza of the /etc/security/audit/config file.
#more /etc/security/audit/config
If the class(es) the USER_Login, USER_Logout, INIT_Start, INIT_End, and USER_SU events are not associated with the default user and all the system users in the users: stanza, this is a finding.
Fix
Edit /etc/security/audit/events and add the USER_Login, USER_Logout, INIT_Start, INIT_End, and USER_SU events to the list of audited events.Edit /etc/security/audit/config and add the USER_Login, USER_Logout, INIT_Start, INIT_End, and USER_SU audit events to an audit class in the classes: stanza.
Edit the /etc/security/audit/config and assign the audit classes with the USER_Login, USER_Logout, INIT_Start, INIT_End, and USER_SU events to the all users listed in the users: stanza.
V-819
No Change
Findings ID: | GEN002820 | Rule ID: | SV-38857r1_rule | Severity: | medium | CCI: | CCI-000126 |
---|
Discussion
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-3Checks
Check the system's audit configuration.# more /etc/security/audit/events
Confirm the following events are configured:
FILE_Acl, FILE_Fchmod, FILE_Fchown, FILE_Mode, and
FILE_Owner.
If any of these events are not configured, this is a finding.
Check the FILE_Acl, FILE_Fchmod, FILE_Fchown, FILE_Mode, and FILE_Owner audit events are defined in the audit classes' stanza classes: of the /etc/security/audit/config file.
#more /etc/security/audit/config
Make note of the audit class(es) the FILE_Acl, FILE_Fchmod, FILE_Fchown, FILE_Mode, and
FILE_Owner events are associated with.
If the FILE_Acl, FILE_Fchmod, FILE_Fchown, FILE_Mode, and
FILE_Owner events are not associated with any audit classes in the classes: stanza, this is a finding.
Verify the audit class is associated with the default user and all other user ids listed in the users: stanza of the /etc/security/audit/config file.
If the class(es) the FILE_Acl, FILE_Fchmod, FILE_Fchown, FILE_Mode, and FILE_Owner events are not associated with the default user and all the system users in the users: stanza, this is a finding.
Fix
Edit /etc/security/audit/events and add the FILE_Acl, FILE_Fchmod, FILE_Fchown, FILE_Mode, and FILE_Owner events to the list of audited events.Edit /etc/security/audit/config and add the FILE_Acl, FILE_Fchmod, FILE_Fchown, FILE_Mode, and FILE_Owner audit events to an audit class in the classes: stanza.
Edit the /etc/security/audit/config and assign the audit classes with the FILE_Acl, FILE_Fchmod, FILE_Fchown, FILE_Mode, and FILE_Owner events to the all users listed in the users: stanza.
V-821
No Change
Findings ID: | GEN003720 | Rule ID: | SV-821r2_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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 which could weaken the system's security posture.System AdministratorECLP-1Checks
Check the ownership of inetd.conf file.Procedure:
# ls -lL /etc/inetd.conf
This is a finding if any of the above files or directories are not owned by root or bin.
Fix
Change the ownership of the inetd.conf file to root or bin.Procedure:
# chown root /etc/inetd.conf
V-822
No Change
Findings ID: | GEN003740 | Rule ID: | SV-822r2_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the mode of inetd.conf file.# ls -lL /etc/inetd.conf
If the mode of the file(s) is more permissive than 0440, this is a finding.
Fix
Change the mode of the inetd.conf file.# chmod 0440 /etc/inetd.conf
V-823
No Change
Findings ID: | GEN003760 | Rule ID: | SV-823r2_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
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
Change the ownership of the services file to root or bin.Procedure:
# chown root /etc/services
V-824
No Change
Findings ID: | GEN003780 | Rule ID: | SV-824r2_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the mode of the services file.Procedure:
# ls -lL /etc/services
If the services file has a mode more permissive than 0444, this is a finding.
Fix
Change the mode of the services file to 0444 or less permissive.Procedure:
# chmod 0444 /etc/services
V-825
No Change
Findings ID: | GEN001780 | Rule ID: | SV-38893r1_rule | Severity: | low | CCI: | CCI-000366 |
---|
Discussion
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-1Checks
Check global initialization files for the presence of mesg -n or mesg n.Procedure:
# grep "mesg" /etc/.login /etc/profile /etc/bashrc /etc/environment /etc/security/environ /etc/security/.profile /etc/csh.login /etc/csh.cshrc
If no global initialization files contain mesg -n or mesg n, this is a finding.
Fix
Edit /etc/profile or another global initialization script and add the mesg -n command.
V-827
No Change
Findings ID: | GEN003900 | Rule ID: | SV-38883r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
Having the "+" character in the hosts.lpd (or equivalent) file allows all hosts to use local system print resources.System AdministratorECCD-1, ECCD-2Checks
Look for the presence of a print service configuration file.Procedure:
# find /etc -name hosts.lpd -print
# find /etc -name Systems -print
# find /etc -name printers.conf
If none of the files are found, this check should be marked not applicable.
Otherwise, examine the configuration file.
Procedure:
# more <print service file>
Check for entries containing a "+" character by itself on any line. If any are found, this is a finding.
Fix
Remove the "+" entries from the hosts.lpd (or equivalent) file.
V-828
No Change
Findings ID: | GEN003920 | Rule ID: | SV-828r2_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Locate any print service configuration file on the system. Consult vendor documentation to verify the names and locations of print service configuration files on the system.Procedure:
# find /etc -name hosts.lpd -print
# find /etc -name Systems -print
If no print service configuration file is found, this is not applicable.
Check the ownership of the print service configuration file(s).
Procedure:
# ls -lL <print service file>
If the owner of the file is not root, sys, bin, or lp, this is a finding.
Fix
Change the owner of the /etc/hosts.lpd file (or equivalent, such as /etc/lp/Systems) to root, lp, or another privileged UID. Consult vendor documentation to determine the name and location of print service configuration files.Procedure:
# chown root /etc/hosts.lpd
V-829
No Change
Findings ID: | GEN003940 | Rule ID: | SV-829r2_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Locate any print service configuration file on the system. Consult vendor documentation for the name and location of print service configuration files.Procedure:
# find /etc -name hosts.lpd -print
# find /etc -name Systems -print
If no print service configuration file is found, this is not applicable.
Check the mode of the print service configuration file.
Procedure:
# ls -lL <print service file>
If the mode of the print service configuration file is more permissive than 0644, this is a finding.
Fix
Change the mode of the /etc/hosts.lpd file (or equivalent, such as /etc/lp/Systems) to 0644 or less permissive. Consult vendor documentation for the name and location of print service configuration files.Procedure:
# chmod 0644 /etc/hosts.lpd
V-831
No Change
Findings ID: | GEN004360 | Rule ID: | SV-40836r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
If the alias file is not owned by root, an unauthorized user may modify the file to add aliases to run malicious code or redirect email.System AdministratorECLP-1Checks
Check the ownership of the alias file.Procedure:
# ls -lL /etc/mail/aliases
If the file is not owned by root, this is a finding.
Fix
Change the owner of the /etc/mail/aliases file (or equivalent, such as /usr/lib/aliases) to root.Procedure:
# chown root /etc/mail/aliases
V-832
No Change
Findings ID: | GEN004380 | Rule ID: | SV-40684r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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 email.System AdministratorECLP-1Checks
Check the mode of the alias file.Procedure:
# ls -lL /etc/mail/aliases
If the alias file has a mode more permissive than 0644, this is a finding.
Fix
Change the mode of the /etc/mail/aliases file.Procedure:
# chmod 0644 /etc/mail/aliases
V-833
No Change
Findings ID: | GEN004400 | Rule ID: | SV-39506r1_rule | Severity: | high | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Find the aliases file on the system.Procedure:
# find / -name aliases -depth -print
# more < aliases file location >
Examine the aliases file for any directories or paths that may be utilized.
Procedure:
# ls -lL < path >
Check if the file or parent directory is owned by root. If not, this is a finding.
Fix
Edit the /etc/mail/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 filename
V-834
No Change
Findings ID: | GEN004420 | Rule ID: | SV-834r2_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
If a file executed through a mail alias file has permissions greater than 0755, it can be modified by an unauthorized user and may contain malicious code or instructions possibly compromising the system.System AdministratorECLP-1Checks
Find the aliases file on the system.Procedure:
# find / -name aliases -depth -print
Examine the aliases file for any directories or paths that may be utilized.
Procedure:
# more <aliases file location>
Check the permissions for any paths referenced.
Procedure:
# ls -lL <path>
If any file referenced from the aliases file has a mode more permissive than 0755, this is a finding.
Fix
Use the chmod command to change the access permissions for files executed from the alias file.For example:
# chmod 0755 < filename >
V-835
No Change
Findings ID: | GEN004440 | Rule ID: | SV-38916r1_rule | Severity: | low | CCI: | CCI-000366 |
---|
Discussion
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 AdministratorECAR-1, ECAR-2, ECAR-3Checks
Check if Sendmail logging is set to level 9.Procedure:
# grep "O L" /etc/mail/sendmail.cf
OR
# grep LogLevel /etc/mail/sendmail.cf
If logging is set to less than 9, this is a finding.
Fix
Edit the sendmail.conf file, locate the "O L" or LogLevel entry and change it to 9.
V-836
No Change
Findings ID: | GEN004460 | Rule ID: | SV-39155r1_rule | Severity: | medium | CCI: | CCI-000126 |
---|
Discussion
If informational and more severe SMTP service messages are not logged, malicious activity on the system may go unnoticed.System AdministratorECSC-1Checks
Check the syslog configuration file for mail.crit logging configuration. The syslog.conf file critical mail logging option line will typically appear as one of the following examples:mail.crit /var/log/syslog
*.crit /var/log/syslog
mail.* /var/log/syslog
Procedure:
# more /etc/syslog.conf
If syslog is not configured to log critical Sendmail messages, this is a finding.
Fix
Edit the syslog.conf file and add a configuration line specifying an appropriate destination for mail.crit syslogs.
V-837
No Change
Findings ID: | GEN004480 | Rule ID: | SV-837r2_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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 AdministratorECLP-1Checks
Locate any mail log files by checking the syslog configuration file.Procedure:
# more /etc/syslog.conf
Identify any log files configured for the mail service at any severity level, or those configured for all services. Check the ownership of these log files.
Procedure:
# ls -lL <file location>
If any mail log file is not owned by root, this is a finding.
Fix
Change the ownership of the Sendmail log file.# chown root <sendmail log file>
V-838
No Change
Findings ID: | GEN004500 | Rule ID: | SV-838r2_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
If the SMTP service log file is more permissive than 0644, unauthorized users may be allowed to change the log file.System AdministratorECLP-1Checks
Check the mode of the SMTP service log file.Procedure:
# more /etc/syslog.conf
Check the configuration to determine which log files contain logs for mail.crit, mail.debug, or *.crit.
Procedure:
# ls -lL <file location>
If the log file permissions are greater than 0644, this is a finding.
Fix
Change the mode of the SMTP service log file.Procedure:
# chmod 0644 <sendmail log file>
V-840
No Change
Findings ID: | GEN004880 | Rule ID: | SV-28403r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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 AdministratorECCD-1, ECCD-2
Checks
Fix
Create a /etc/ftpusers file containing a list of accounts not authorized for FTP.
V-841
No Change
Findings ID: | GEN004900 | Rule ID: | SV-28406r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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 AdministratorChecks
Check the contents of the ftpusers file. If the system has accounts not allowed to use FTP and are not listed in the ftpusers file, this is a finding.# more /etc/ftpusers
Fix
Add accounts not allowed to use FTP to the /etc/ftpusers file.
V-842
No Change
Findings ID: | GEN004920 | Rule ID: | SV-28409r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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
Check the ownership of the ftpusers file.# ls -l /etc/ftpusers
If the ftpusers file is not owned by root, this is a finding.
Fix
Change the owner of the ftpusers file to root.# chown root /etc/ftpusers
V-843
No Change
Findings ID: | GEN004940 | Rule ID: | SV-28412r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the permissions of the ftpusers file.# ls -l /etc/ftpusers
If the ftpusers file has a mode more permissive than 0640, this is a finding.
Fix
Change the mode of the ftpusers file to 0640.# chmod 0640 /etc/ftpusers
V-845
No Change
Findings ID: | GEN004980 | Rule ID: | SV-38991r1_rule | Severity: | low | CCI: | CCI-000130 |
---|
Discussion
The -l option allows logging of connections. 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-3Checks
Perform:# grep ftpd /etc/inetd.conf,
Check the line for ftpd to check if the -l argument. If the ftpd is invoked without the -l argument, this is a finding.
Check the /etc/syslog.conf file for daemon.info or *.info.
# more /etc/syslog.conf
If daemon.info or *.info is not being logged, this is a finding.
Fix
Edit the /etc/inetd.conf file and add the -l argument to the ftpd service line.# vi /etc/inetd.conf
Restart inetd.conf
# refresh -s inetd
Add daemon.info or *.info to the /etc/syslog.conf file.
#vi /etc/syslog.conf
*.info /var/log/syslog
Restart the syslog daemon.
# refresh -s syslogd
V-846
No Change
Findings ID: | GEN004820 | Rule ID: | SV-40086r1_rule | Severity: | medium | CCI: | CCI-001475 |
---|
Discussion
Due to the numerous vulnerabilities inherent in anonymous FTP, it is recommended that it not be used. If anonymous FTP must be used on a system, the requirement must be authorized and approved in the system accreditation package.trueInformation Assurance OfficerSystem AdministratorECSC-1Checks
Attempt to log into this host with a user name of anonymous and a password of guest (also try the password of [email protected]). If the logon is successful, this is a finding.Procedure:
# ftp localhost
Name: anonymous
530 Guest login not allowed on this machine.
Fix
Remove user "anonymous" from /etc/passwd.
V-847
No Change
Findings ID: | GEN005080 | Rule ID: | SV-28420r1_rule | Severity: | high | CCI: | CCI-000366 |
---|
Discussion
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
If the system is not running tftp, this is not applicable.Determine if tftpd is running in secure mode.
# more /etc/tftpaccess.ctl
If the file does not exist, this is a finding. If the file does not contain an entry restricting access to the tftp user home directory, this is a finding. If other configuration is in the file, this is a finding.
Fix
Edit /etc/tftpaccess.ctl to only contain an entry restricting access to the tftp user home directory.
V-848
No Change
Findings ID: | GEN005100 | Rule ID: | SV-848r2_rule | Severity: | high | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the mode of the TFTP daemon.Procedure:
# find / -name "*tftpd" -print
# ls -lL <file location>
If the mode of the file is more permissive than 0755, this is a finding.
Fix
Change the mode of the TFTP daemon.Procedure:
# chmod 0755 <tftp server>
V-849
No Change
Findings ID: | GEN005120 | Rule ID: | SV-849r2_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
If TFTP has a valid shell, it increases the likelihood of someone logging to the TFTP account and compromising the system.System AdministratorECSC-1Checks
Check the /etc/passwd file to determine if TFTP is configured properly.Procedure:
# 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
Create a 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.
V-867
No Change
Findings ID: | GEN006400 | Rule ID: | SV-867r2_rule | Severity: | medium | CCI: | CCI-001435 |
---|
Discussion
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-1Checks
Perform the following to determine if NIS is active on the system.# ps -ef | egrep '(ypbind|ypserv)'
If NIS is found active on the system, this is a finding.
Fix
Disable the use of NIS. Possible replacements are NIS+ and LDAP.
V-899
No Change
Findings ID: | GEN001440 | Rule ID: | SV-27186r1_rule | Severity: | low | CCI: | CCI-000225 |
---|
Discussion
If users do not have a valid home directory, there is no place for the storage and control of files they own.System AdministratorECSC-1Checks
Use usrck to verify home directory assignments are present.Procedure:
# usrck -n ALL
If any user is not assigned a home directory, this is a finding.
Fix
Assign a home directory to any user without one.
V-900
No Change
Findings ID: | GEN001460 | Rule ID: | SV-27194r1_rule | Severity: | low | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Use pwck to check that assigned home directories exist.Procedure:
# usrck -n ALL
If any user's assigned home directory does not exist, this is a finding.
Fix
If a user has no home directory, determine why. If possible, delete accounts with no home directory. If the account is valid, then create the home directory using the appropriate system administration utility or manually create, i.e., mkdir <directory name>; copy the skeleton files into the directory; chown <user name> <directory name> for the new directory and the skeleton files. Document all changes.
V-901
No Change
Findings ID: | GEN001480 | Rule ID: | SV-901r2_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
Excessive permissions on home directories allow unauthorized access to user's files.System AdministratorECLP-1Checks
Check the home directory mode of each user in /etc/passwd.Procedure:
# cut -d : -f 6 /etc/passwd | xargs -n1 ls -ld | more
If a user's 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
Change the mode of users' home directories to 0750 or less permissive.Procedure (example):
# chmod 0750 <home directory>
V-902
No Change
Findings ID: | GEN001500 | Rule ID: | SV-902r2_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
If users do not own their home directories, unauthorized users could access user files.System AdministratorECLP-1Checks
Check the ownership of each user's home directory listed in the /etc/passwd file.Procedure:
# ls -lLd <user home directory>
If any user's home directory is not owned by the assigned user, this is a finding.
Fix
Change the owner of a user's home directory to its assigned user.Procedure:
# chown <user> <home directory>
V-903
No Change
Findings ID: | GEN001520 | Rule ID: | SV-903r2_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
If the GID of the home directory is not the same as the GID of the user, this would allow unauthorized access to files.System AdministratorECLP-1Checks
Check the group ownership for each user in the /etc/passwd file.Procedure:
# ls -lLd <user home directory>
If any user's 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
Change the group owner for user's home directories to the primary group of the assigned user.Procedure:
# chgrp groupname directoryname
(Replace examples with appropriate group and home directory.)
Document all changes.
V-905
No Change
Findings ID: | GEN001880 | Rule ID: | SV-905r2_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the modes 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 (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, the .dt directory or the .dtprofile file is more permissive than 0755, this is a finding.
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.
V-906
No Change
Findings ID: | GEN001580 | Rule ID: | SV-38732r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check run control script modes.# cd /etc
# find rc* -ls
If any run control script has a mode more permissive than 0755, this is a finding.
Fix
Ensure all system startup files have mode 0755 or less permissive. Examine the rc files, 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 the files are world-writable, use the chmod command to correct the vulnerability and research why they are world-writable.Procedure:
# chmod 755 startupfile
Document all changes.
V-907
Updated
Findings ID: | GEN001600 | Rule ID: | SV-41074r |
Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
The executable search path (typically the PATH environment variable) contains a list of directories for the shell to search to find executables.Checks
Verify run control scripts' library search paths.Procedure:
# grep -r PATH /etc/rc*
This variable is formatted as a colon-separated list of directories.
Relative path entries must be document with the ISSO.
If there is an empty entry, such as a leading or trailing colon
If an entry begins with a character other than a slash (/)
Fix
Edit the run control script and remove the relative path entrEdit the run control script and remove any empty entry that is defined.
V-910
No Change
Findings ID: | GEN001640 | Rule ID: | SV-910r2_rule | Severity: | high | CCI: | CCI-000225 |
---|
Discussion
World-writable files could be modified accidentally or maliciously to compromise system integrity.System AdministratorECCD-1, ECCD-2Checks
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
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>
V-913
No Change
Findings ID: | GEN002000 | Rule ID: | SV-913r2_rule | Severity: | medium | CCI: | CCI-000196 |
---|
Discussion
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-2Checks
Check the system for the existence of any .netrc files.Procedure:
# find / -name .netrc
If any .netrc file exists, this is a finding.
Fix
Remove the .netrc file(s).Procedure:
# rm .netrc
V-914
No Change
Findings ID: | GEN001540 | Rule ID: | SV-914r2_rule | Severity: | low | CCI: | CCI-000225 |
---|
Discussion
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-2Checks
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> ! \( -name .login -o -name .cshrc -o -name .logout -o -name .profile -o -name .bash_profile -o -name .bashrc -o -name .env -o -name .dtprofile -o -name .dispatch -o -name .emacs -o -name .exrc \) -exec ls -ld {} \;
If user's home directories contain files or directories not owned by the home directory owner, this is a finding.
Fix
Change the ownership of files and directories in user's home directories to the owner of the home directory.Procedure:
# chown accountowner filename
OR
# find /<usershomedirectory> ! -fstype nfs ! -user <username> ! /( -name .login -o -name .cshrc -o -name .logout -o -name .profile -o -name .bash_profile -o -name .bashrc -o -name .env -o -name .dtprofile -o -name .dispatch -o -name .emacs -o -name .exrc \) -exec chown <username> {} \;
V-915
No Change
Findings ID: | GEN001560 | Rule ID: | SV-915r2_rule | Severity: | low | CCI: | CCI-000225 |
---|
Discussion
Excessive permissions allow unauthorized access to user's files.trueSystem AdministratorInformation Assurance OfficerECLP-1
Checks
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 ! \( -name .login -o -name .cshrc -o -name .logout -o -name .profile -o -name .bash_profile -o -name .bashrc -o -name .env -o -name .dtprofile -o -name .dispatch -o -name .emacs -o -name .exrc \) \( -perm -0001 -o -perm -0002 -o -perm -0004 -o -perm -0020 -o -perm -2000 -o -perm -4000 \) -exec ls -ld {} \;
If user's home directories contain files or directories more permissive than 0750, this is a finding.
Fix
Change the mode of files and directories within user's home directories to 0750.Procedure:
# chmod 0750 filename
Document all changes.
V-916
No Change
Findings ID: | GEN002120 | Rule ID: | SV-38741r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
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 shell that may not be secure.System AdministratorECSC-1Checks
Check /etc/security/login.cfg for a shells stanza.Procedure:
# grep -p usw: /etc/security/login.cfg | grep "shells ="
If no such stanza exists, this is a finding.
Check the /etc/shells file.
Procedure:
# more /etc/shells
If the /etc/shells file does not exist, this is a finding.
Fix
Edit the /etc/security/login.cfg file and add a shells stanza containing a list of valid shells.#chsec -f /etc/security/login.cfg -s usw -a shells=<list of approved shells>
Create the /etc/shells file.
#vi /etc/shells
V-917
No Change
Findings ID: | GEN002140 | Rule ID: | SV-38742r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
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 shell that may not be secure.System AdministratorECSC-1Checks
Confirm the login shells referenced in the /etc/passwd file are listed in the /etc/security/login.cfg file's shells =variable in the usw stanza.# more /etc/security/login.cfg
# more /etc/shells
The /usr/bin/false, /bin/false, /dev/null, /sbin/nologin, (and equivalents), and sdshell will be considered valid shells for use in the /etc/passwd file, but will not be listed in the shells stanza. If a shell referenced in /etc/passwd is not listed in the shells stanza, excluding the above mentioned shells, then this is a finding.
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.Alternatively, use the SMIT to change the /etc/passwd shell entry.
V-918
No Change
Findings ID: | GEN000760 | Rule ID: | SV-38840r1_rule | Severity: | medium | CCI: | CCI-000017 |
---|
Discussion
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
Indications of inactive accounts are those without entries in the last log. Check the date in the last log to verify it is within the last 35 days. If an inactive account is not disabled via an invalid login shell /bin/false entry in the shell field of the /etc/passwd file or account_locked = true in /etc/security/user file, this is a finding.Fix
All inactive accounts will have /bin/false, /usr/bin/false, or /dev/null as the default shell in the /etc/passwd file and have the password disabled. Disable the inactive accounts. Examine the inactive 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, then disable them by placing a shell of /bin/false or /dev/null in the shell field of the passwd file entry for that account. An alternative, and preferable method, is to disable the account using SMIT or the chsec command.Change the accounts login shell.
#chsh <account> /bin/false
Lock the account in /etc/security/user file.
#chuser account_locked=true < user id >
OR
# smitty chuser
V-921
No Change
Findings ID: | GEN002200 | Rule ID: | SV-38847r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Obtain a list of system shells from /etc/security/login.cfg and check the ownership of these shells.Procedure:
#grep shells /etc/security/login.cfg | grep -v \* | cut -f 2 -d = | sed s/,/\ /g | xargs -n1 ls -l
If any shell is not owned by root or bin, this is a finding.
Obtain a list of system shells from /etc/shells and check the ownership of these shells.
Procedure:
#cat /etc/shells | xargs -n1 ls -l
If any shell is not owned by root or bin, this is a finding.
Fix
Change the ownership of the shell with incorrect ownership.# chown root < shell >
V-922
No Change
Findings ID: | GEN002220 | Rule ID: | SV-38846r1_rule | Severity: | high | CCI: | CCI-000225 |
---|
Discussion
Shells with world/group write permissions give the ability to maliciously modify the shell to obtain unauthorized access.System AdministratorECLP-1Checks
Obtain a list of system shells from /etc/security/login.cfg and check the permissions of these shells.Procedure:
#grep shells /etc/security/login.cfg | grep -v \* | cut -f 2 -d = | sed s/,/\ /g | xargs -n1 ls -l
If any shell has a mode more permissive than 0755, this is a finding.
Obtain a list of system shells from /etc/shells and check the ownership of these shells.
Procedure:
#cat /etc/shells | xargs -n1 ls -l
If any shell has a mode more permissive than 0755, this is a finding.
Fix
Change the mode of the shell.# chmod 0755 < shell >
V-923
No Change
Findings ID: | GEN002260 | Rule ID: | SV-923r2_rule | Severity: | low | CCI: | CCI-000318 |
---|
Discussion
If an unauthorized device is allowed to exist on the system, there is the possibility the system may perform unauthorized operations.System AdministratorInformation Assurance OfficerECSC-1Checks
Check the system for an automated job, or check with the SA, to determine if the system is checked for extraneous device files on a weekly basis. If no automated or manual process is in place, this is a finding.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.Generate a list of device files.
# find / -type b -o -type c > device-file-list
V-924
Updated
Findings ID: | GEN002280 | Rule ID: | SV-924r |
Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
System device files in writable directories could be modified, removed, or used by an unprivileged user to control system hardware.System AdministratorChecks
Find all device files existing anywhere on the system.Procedure:
# find / -type b -print > devicelist
# find / -type c -print >> devicelist
Check the permissions on the directories above subdirectories containing device files.
The following list of device files are intended to be world-writable and if present are not a finding.
/dev/arp
/dev/conslog
/dev/crypto
/dev/dtrace/dtrace
/dev/dtrace/helper
/dev/dtrace/provider/fasttrap
/dev/fd/*
/dev/kstat
/dev/null
/dev/poll
/dev/pool
/dev/ptmx
/dev/sad/user
/dev/tcp
/dev/tcp6
/dev/ticlts
/dev/ticots
/dev/ticotsord
/dev/tty
/dev/udp
/dev/udp6
/dev/zero
/dev/zfs
If any device file or their parent directory is world-writable and it is not intended to be world-writable,
Fix
Remove the world-writable permission from the device file(s).Procedure:
# chmod o-w <device file>
Document all changes.
V-925
No Change
Findings ID: | GEN002300 | Rule ID: | SV-38745r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-2Checks
Check the system for world-writable device files.Procedure:
# find / -perm -2 -a \( -type b -o -type c \) -exec ls -ld {} \;
If any device file(s) used for backup are writable by users other than root, this is a finding (Typical backup devices for tape are/dev/rmt* and cd/dvd writers are /dev/cd*).
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.
V-926
No Change
Findings ID: | GEN006460 | Rule ID: | SV-926r2_rule | Severity: | medium | CCI: | CCI-001435 |
---|
Discussion
If the NIS+ server is not operating in, at least, security level 2, there is no encryption and the system could be penetrated by intruders and/or malicious users.System AdministratorECSC-1Checks
If the system is not using NIS+, this is not applicable.Check the system to determine if NIS+ security level 2 is implemented.
Procedure:
# niscat cred.org_dir
If the second column does not contain DES, the system is not using NIS+ security level 2, and this is a finding.
Fix
Configure the NIS+ server to use security level 2.
V-928
No Change
Findings ID: | GEN005740 | Rule ID: | SV-28445r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
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
Change the owner of the exports file to root.Example:
# chown root /etc/exports
V-929
No Change
Findings ID: | GEN005760 | Rule ID: | SV-28447r1_rule | Severity: | low | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Fix
# chmod 0644 /etc/exports
V-931
No Change
Findings ID: | GEN005800 | Rule ID: | SV-931r2_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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 AdministratorChecks
Check for NFS exported file systems.Procedure:
# exportfs -v
This will display all of the exported file systems. For each file system displayed, check the ownership.
Procedure:
# ls -lLa <exported file system path>
If the files and directories are not owned by root, this is a finding.
Fix
Change the ownership of exported file systems not owned by root.Procedure:
# chown root <path>
V-932
No Change
Findings ID: | GEN005820 | Rule ID: | SV-38956r1_rule | Severity: | medium | CCI: | CCI-000062 |
---|
Discussion
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-1Checks
Check if the anon option is set correctly for exported file systems.List exported file systems.
# exportfs -v
Each of the exported file systems should include an entry for the 'anon=' option set to -1 or an equivalent (60001, 60002, 65534, or 65535). If an appropriate 'anon=' setting is not present for an exported file system, this is a finding.
Fix
Edit /etc/exports and set the anon=-1 option for exported file systems without it. Re-export the file systems.# exportfs -a
V-933
No Change
Findings ID: | GEN005840 | Rule ID: | SV-41524r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
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-1Checks
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
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.
V-936
No Change
Findings ID: | GEN005900 | Rule ID: | SV-38957r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the system for NFS mounts not using the nosuid option.Procedure:
# lsfs -v nfs
If the mounted file systems do not have the nosuid option, this is a finding.
Fix
Edit /etc/filesystems and add the nosuid option for all NFS file systems. Remount the NFS file systems to make the change take effect.
V-940
No Change
Findings ID: | GEN006580 | Rule ID: | SV-38959r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
Access control programs (such as TCP_WRAPPERS) provide the ability to enhance system security posture.System AdministratorEBRU-1Checks
Determine if TCP_WRAPPERS is being used.# grep tcpd /etc/inetd.conf
If no services are listed, this is a finding.
Fix
Edit /etc/inetd.conf and use tcpd to wrap services.Use SMIT to install TCP Wrappers from the AIX Expansion pack media as fileset netsec.options.tcpwrappers.
V-969
No Change
Findings ID: | GEN000000-AIX00020 | Rule ID: | SV-969r2_rule | Severity: | medium | CCI: | CCI-000032 |
---|
Discussion
The AIX Trusted Computing Base (TCB) software provides protection from the unauthorized modification of core system files.System AdministratorECSC-1Checks
Perform:# /bin/tcbck
If TCB is not installed, the output will show an error code of 3001-101 and/or a text message indicating TCB is not installed, this is a finding.
Fix
Ensure the Trusted Computing Base (TCB) software is implemented. TCB can only be installed at OS installation time.
V-974
No Change
Findings ID: | GEN002960 | Rule ID: | SV-27318r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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 neither cron.allow nor cron.deny exists, then any account may use the cron facility. This may open the facility up for abuse by system intruders and malicious users.System AdministratorECLP-1Checks
Check for the existence of the cron.allow and cron.deny files.# ls -lL /var/adm/cron/cron.allow
# ls -lL /var/adm/cron/cron.deny
If neither file exists, this is a finding.
Fix
Create /var/adm/cron/cron.allow and/or /var/adm/cron/cron.deny with appropriate content.
V-975
No Change
Findings ID: | GEN002980 | Rule ID: | SV-27324r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
A cron.allow file that is readable and/or writable by 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-1Checks
Check mode of the cron.allow file.Procedure:
# ls -lL /var/adm/cron/cron.allow
If the file has a mode more permissive than 0600, this is a finding.
Fix
Change the mode of the cron.allow file to 0600.Procedure:
# chmod 0600 /var/adm/cron/cron.allow
V-976
No Change
Findings ID: | GEN003000 | Rule ID: | SV-27329r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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
List all cronjobs on the system.Procedure:
# ls /var/spool/cron/crontabs/
If cron jobs exist under any of the above directories search for programs executed by cron.
Procedure:
# more <cron job file>
Determine if the file is group-writable or world-writable.
Procedure:
# ls -la <cron program file>
If cron executes group-writable or world-writable files, this is a finding.
Fix
Remove the world-writable and group-writable permissions from the cron program file(s) identified.# chmod go-w <cron program file>
V-977
No Change
Findings ID: | GEN003020 | Rule ID: | SV-38947r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
List all cronjobs on the system.Procedure:
# ls /var/spool/cron/crontabs/
If cron jobs exist under any of the above directories search for programs executed by cron.
Procedure:
# more <cron job file>
Determine if the directory containing programs executed from cron is world-writable.
Procedure:
# ls -ld <cron program directory>
If cron executes programs in world-writable directories, this is a finding.
Fix
Remove the world-writable permission from the cron program directories identified.Procedure:
# chmod o-w <cron program directory>
V-978
No Change
Findings ID: | GEN003080 | Rule ID: | SV-27340r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
To protect the integrity of scheduled system jobs and prevent malicious modification to these jobs, crontab files must be secured.System AdministratorECLP-1
Checks
Check the mode of the crontab files.# ls -lL /var/spool/cron/crontabs/
If any crontab file has a mode more permissive than 0600, this is a finding.
Fix
Change the mode of the crontab files.# chmod 0600 /var/spool/cron/crontabs/*
V-979
No Change
Findings ID: | GEN003100 | Rule ID: | SV-27342r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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
Check the mode of the crontab directory.# ls -ld /var/spool/cron/crontabs
If the mode of the crontab directory is more permissive than 0755, this is a finding.
Fix
Change the mode of the crontab directory.# chmod 0755 /var/spool/cron/crontabs
V-980
No Change
Findings ID: | GEN003120 | Rule ID: | SV-27345r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the owner of the crontab directory.# ls -ld /var/spool/cron/crontabs
If the owner of the crontab directory is not root or bin, this is a finding.
Fix
Change the owner of the crontab directory.# chown root /var/spool/cron/crontabs
V-981
No Change
Findings ID: | GEN003140 | Rule ID: | SV-39104r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the group owner of cron and crontab directories.Procedure:
# ls -ld /var/spool/cron/crontabs
If a cron or crontab directory is not group-owned by sys, system, bin, or cron, this is a finding.
Fix
Change the group owner of the crontab directories to sys, system, bin, or cron.Procedure: #
chown cron /var/spool/cron/crontabs
V-982
No Change
Findings ID: | GEN003160 | Rule ID: | SV-27350r1_rule | Severity: | medium | CCI: | CCI-000126 |
---|
Discussion
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 AdministratorECAR-1, ECAR-2, ECAR-3
Checks
# ls -lL /var/adm/cron/logIf this file does not exist or is older than the last cron job, this is a finding.
Fix
Enable cron logging on the system.
V-983
No Change
Findings ID: | GEN003180 | Rule ID: | SV-27355r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
Cron logs contain reports of scheduled system activities and must be protected from unauthorized access or manipulation.System AdministratorECLP-1, ECTP-1
Checks
Check the mode of the cron log file.# ls -lL /var/adm/cron/log
If the mode is more permissive than 0600, this is a finding.
Fix
Change the mode of the cron log file.# chmod 0600 /var/adm/cron/log
V-984
No Change
Findings ID: | GEN003280 | Rule ID: | SV-27377r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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 AdministratorECLP-1Checks
Check for the existence of at.allow and at.deny files.# ls -lL /var/adm/cron/at.allow
# ls -lL /var/adm/cron/at.deny
If neither file exists, this is a finding.
Fix
Create at.allow and/or at.deny files containing appropriate lists of users to be allowed or denied access to the "at" daemon.
V-985
No Change
Findings ID: | GEN003300 | Rule ID: | SV-27381r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
# more /var/adm/cron/at.denyIf the at.deny file exists and is empty, this is a finding.
Fix
Add appropriate users to the at.deny file, or remove the empty at.deny file if an at.allow file exists.
V-986
No Change
Findings ID: | GEN003320 | Rule ID: | SV-27385r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
# more /var/adm/cron/at.allowIf default accounts (such as bin, sys, adm, and others) are listed in the at.allow file, this is a finding.
Fix
Remove the default accounts (such as bin, sys, adm, and others) from the at.allow file.
V-987
No Change
Findings ID: | GEN003340 | Rule ID: | SV-27389r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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
Check the mode of the at.allow file.# ls -lL /var/adm/cron/at.allow
If the at.allow file has a mode more permissive than 0600, this is a finding.
Fix
Change the mode of the at.allow file.# chmod 0600 /var/adm/cron/at.allow
V-988
No Change
Findings ID: | GEN003360 | Rule ID: | SV-988r2_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
List the "at" jobs on the system.Procedure:
# ls -la /var/spool/cron/atjobs /var/spool/atjobs
For each "at" job file, determine which programs are executed.
Procedure:
# more <at job file>
Check 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
Remove group-write and world-write permissions from files executed by "at" jobs.Procedure:
# chmod go-w <file>
V-989
No Change
Findings ID: | GEN003380 | Rule ID: | SV-989r2_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
List any "at" jobs on the system.Procedure:
# ls /var/spool/cron/atjobs /var/spool/atjobs
For each "at" job, determine which programs are executed.
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
Remove the world-writable permission from directories containing programs executed by "at".Procedure:
# chmod o-w <at program directory>
V-993
No Change
Findings ID: | GEN005300 | Rule ID: | SV-38889r1_rule | Severity: | high | CCI: | CCI-000178 |
---|
Discussion
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-1Checks
Check the SNMP configuration for default passwords.Locate and examine the SNMP configuration.
Procedure:
# find / -name "snmp*.conf" -print
# more <snmpd.conf>
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
Change the default passwords. To change them, locate the file /etc/snmpd.conf or the file /etc/snmpd3.conf. Edit the file. Locate the line system-group-read-community which has a default password of public and make the password something more random (less guessable). Do the same for the lines that read 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.
V-994
No Change
Findings ID: | GEN005320 | Rule ID: | SV-38817r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
The snmpd.conf file contains authenticators and must be protected from unauthorized access and modification.System AdministratorECLP-1Checks
Check the mode of the SNMP daemon configuration file.Locate the SNMP daemon configuration file. Consult vendor documentation to verify the name and location of the file.
Procedure:
# find / -name "snmpd*.conf"
Check the mode of the SNMP daemon configuration file.
Procedure:
# ls -lL <snmpd conf>
Fix
Change the mode of the SNMP daemon configuration file to 0600.Procedure:
# chmod 0600 /etc/snmpd.conf
# chmod 0600 /etc/snmpdv3.conf
V-995
No Change
Findings ID: | GEN005340 | Rule ID: | SV-995r2_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the modes for all Management Information Base (MIB) files on the system.Procedure:
# find / -name *.mib -print
# ls -lL <mib file>
If any file is returned that does not have mode 0640 or less permissive, this is a finding.
Fix
Change the mode of MIB files to 0640.Procedure:
# chmod 0640 <mib file>
V-1010
No Change
Findings ID: | GEN002480 | Rule ID: | SV-1010r3_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
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 Administrator
Checks
Check the system for world-writable files and directories.Procedure:
# find / -perm -2 -a \( -type d -o -type f \) -exec ls -ld {} \;
If any world-writable files or directories are located, except those required for proper system or application operation, such as /tmp and /dev/null, this is a finding.
Fix
Remove or change the mode for any world-writable file or directory on the system that is not required to be world-writable.Procedure:
# chmod o-w <file/directory>
Document all changes.
V-1011
No Change
Findings ID: | GEN003800 | Rule ID: | SV-38951r1_rule | Severity: | low | CCI: | CCI-000134 |
---|
Discussion
Inetd or xinetd logging and tracing allows the system administrators to observe the IP addresses that are connecting to their machines and to observe 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-1Checks
Determine if inetd or xinetd has logging or tracing enabled.# ps -ef |grep inetd |grep -e "-d"
If no results are returned, this is a finding.
Fix
Edit the inetd startup script to contain the "-d" parameter for the inetd process.#vi /etc/rc.tcpip
# chssys -s inetd -a '-d'
V-1013
No Change
Findings ID: | GEN008600 | Rule ID: | SV-38835r1_rule | Severity: | high | CCI: | CCI-000366 |
---|
Discussion
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 that could compromise or damage the system. It could also allow the system to be used for malicious purposes by a malicious anonymous user.System AdministratorECSC-1Checks
Determine if the system is configured to boot from devices other than the system startup media.# bootlist -m normal -o
The returned values should be hdisk{x}. If the system is setup to boot from a non-hard disk device, this is a finding.
Additionally, ask the SA if the machine is setup for multi-boot in the SMS application. If multi-boot is enabled, the firmware will stop at boot time and request which image to boot from the user. If multi-boot is enabled, this is a finding.
Fix
Configure the system to only boot from system startup media.# bootlist -m normal hdisk< x >
Set multi-boot to off in the SMS application.
V-1023
No Change
Findings ID: | GEN006240 | Rule ID: | SV-1023r2_rule | Severity: | medium | CCI: | CCI-000381 |
---|
Discussion
Internet Network News (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
# ps -ef | egrep "innd|nntpd"If an INN server is running, this is a finding.
Fix
Disable the INN server.
V-1026
No Change
Findings ID: | GEN006080 | Rule ID: | SV-1026r2_rule | Severity: | medium | CCI: | CCI-001436 |
---|
Discussion
SWAT is a tool used to configure Samba. As it modifies Samba configuration, which can impact system security, it 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
Check the system for an enabled SWAT service.# grep -i swat /etc/inetd.conf
If SWAT is found enabled, it must be utilized with SSL to ensure a secure connection between the client and the server. Ask the SA to identify the method used to provide SSL protection for the SWAT service. Verify (or ask the SA to demonstrate) this configuration is effective by accessing SWAT using an HTTPS connection from a web browser.
If SWAT is found enabled and has no SSL protection, this is a finding.
Fix
Disable SWAT (e.g., remove the "swat" line from inetd.conf or equivalent, and restart the service) or configure SSL protection for the SWAT service.
V-1027
No Change
Findings ID: | GEN006100 | Rule ID: | SV-40724r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
The /usr/lib/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-1Checks
Check the ownership of the /usr/lib/smb.conf file.Procedure:
# ls -l /usr/lib/smb.conf
If an smb.conf file is not owned by root, this is a finding.
Fix
Change the ownership of the smb.conf file.Procedure:
# chown root /usr/lib/smb.conf
V-1028
No Change
Findings ID: | GEN006140 | Rule ID: | SV-39229r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
If the smb.conf file has excessive permissions, the file may be maliciously modified and the Samba configuration could be compromised.System AdministratorECLP-1Checks
Check the mode of the smb.conf file.Procedure:
# ls -lL /usr/lib/smb.conf
If the smb.conf has a mode more permissive than 0644, this is a finding.
Fix
Change the mode of the smb.conf file to 0644 or less permissive.Procedure:
# chmod 0644 /usr/lib/smb.conf
V-1029
No Change
Findings ID: | GEN006160 | Rule ID: | SV-40379r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
If the smbpasswd file is not owned by root, the smbpasswd file may be maliciously accessed or modified, potentially resulting in the compromise of Samba accounts.System AdministratorECLP-1Checks
Check the ownership of the smbpasswd file.# ls -l /var/private/smbpasswd
If an smbpasswd file is not owned by root, this is a finding.
Fix
Change the owner of the smbpasswd file to root.# chown root /var/private/smbpasswd
V-1030
No Change
Findings ID: | GEN006220 | Rule ID: | SV-39237r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
Samba increases the attack surface of the system and must be restricted to communicate only with systems requiring access.System AdministratorECSC-1Checks
Examine the smb.conf file.# more /usr/lib/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
Edit the smb.conf file and set the hosts option to permit only authorized hosts to access Samba.
V-1032
No Change
Findings ID: | GEN000540 | Rule ID: | SV-38768r1_rule | Severity: | medium | CCI: | CCI-000198 |
---|
Discussion
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-1Checks
Check the minage field for each user.# /usr/sbin/lsuser -a minage ALL
If the minage field is less than 1 for any user, this is a finding.
Fix
Use SMIT or the chsec command to set the minimum password age to 1 week.# chsec -f /etc/security/user -s default -a minage=1
# chsec -f /etc/security/user -s <user id> -a minage=1
OR
# smitty chuser
V-1046
No Change
Findings ID: | GEN001100 | Rule ID: | SV-39097r1_rule | Severity: | high | CCI: | CCI-000197 |
---|
Discussion
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 AdministratorIAIA-1, IAIA-2Checks
Determine if root has logged in over an unencrypted network connection.First, determine if root has logged in over a network.
Procedure:
# last | grep "^root " | egrep -v "reboot|console" | more
Next, determine if the SSH daemon is running.
Procedure:
# ps -ef |grep sshd
If root has logged in over the network and SSHD is not running, this is a finding.
Fix
Install OpenSSH from AIX installation media or AIX Expansion Pack.#smitty installp
Enable SSH on the system and use it for all remote connections used to attain root access.
Disable direct root login.
# chsec -f /etc/security/user -s root -a rlogin=false
V-1047
No Change
Findings ID: | GEN001120 | Rule ID: | SV-38684r1_rule | Severity: | medium | CCI: | CCI-000770 |
---|
Discussion
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-1Checks
Determine if the SSH daemon is configured to permit root logins.Procedure:
# find / -name sshd_config -ls
# grep -v "^#" <sshd_config path and file> | grep -i permitrootlogin
If the PermitRootLogin entry is not found or is not set to no, this is a finding.
Fix
Edit the /etc/ssh/sshd_config file and set the PermitRootLogin option to no and refresh sshd.#kill -1 <pid of sshd>
V-1048
No Change
Findings ID: | GEN002320 | Rule ID: | SV-27243r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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 to a bugging device.System AdministratorECLP-1
Checks
Check the mode of audio devices.# /usr/sbin/lsdev -C | grep -i audio
# ls -lL /dev/*aud0
If the mode of audio devices are more permissive than 0660, this is a finding.
Fix
Change the mode of audio devices.# chmod o-w <audio device>
V-1049
No Change
Findings ID: | GEN002340 | Rule ID: | SV-27248r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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 to a bugging device.System AdministratorECLP-1
Checks
Check the owner of audio devices.Procedure:
# /usr/sbin/lsdev -C | grep -i audio
# ls -lL /dev/*aud0
If the owner of any audio device file is not root, this is a finding.
Fix
Change the owner of the audio device.# chown root <audio device>
V-1056
No Change
Findings ID: | GEN006120 | Rule ID: | SV-39231r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the group ownership of the smb.conf file.Procedure:
# ls -l /usr/lib/smb.conf
If an smb.conf file is not group-owned by bin, sys, or system, this is a finding.
Fix
Change the group owner of the smb.conf file.Procedure:
# chgrp system /usr/lib/smb.conf
V-1058
No Change
Findings ID: | GEN006180 | Rule ID: | SV-39235r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check smbpasswd ownership.# ls -lL /var/private/smbpasswd
If smbpasswd is not group-owned by sys, or system, this is a finding.
Fix
Use the chgrp command to change the group owner of the smbpasswd file to system.# chgrp system /var/private/smbpasswd
V-1059
No Change
Findings ID: | GEN006200 | Rule ID: | SV-40725r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check smbpasswd mode.Procedure:
# ls -lL /var/private/smbpasswd
If smbpasswd has a mode more permissive than 0600, this is a finding.
Fix
Change the mode of the smbpasswd file to 0600.Procedure:
# chmod 0600 /var/private/smbpasswd
V-1061
No Change
Findings ID: | GEN002360 | Rule ID: | SV-27253r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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 AdministratorECLP-1
Checks
Check the group owner of audio devices.Procedure:
# /usr/sbin/lsdev -C | grep -i audio
# ls -lL /dev/*aud0
If the group owner of an audio device is not root, sys, bin, or system, this is a finding.
Fix
Change the group owner of the audio device.Procedure:
# chgrp system <audio device>
V-4083
No Change
Findings ID: | GEN000500 | Rule ID: | SV-39096r1_rule | Severity: | medium | CCI: | CCI-000057 |
---|
Discussion
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 AdministratorPESL-1Checks
Log into a graphical desktop environment provided by the system. Allow the session to remain idle for 15 minutes. If the desktop session is not automatically locked after 15 minutes, or does not require re-authentication to resume operations, this is a finding.Fix
Consult vendor documentation to determine the settings required for the system to lock graphical desktop environments. Configure the system to lock graphical desktop environments after 15 minutes of inactivity and require re-authentication to resume operations.
V-4084
No Change
Findings ID: | GEN000800 | Rule ID: | SV-38679r1_rule | Severity: | medium | CCI: | CCI-000200 |
---|
Discussion
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 AdministratorIAIA-1, IAIA-2Checks
Fix
Use the chsec command to configure the system to prohibit the reuse of passwords within five iterations.# chsec -f /etc/security/user -s default -a histsize=5
# chuser histsize=5 < user id >
V-4087
No Change
Findings ID: | GEN001940 | Rule ID: | SV-4087r2_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
If start-up files execute world-writable programs, especially in unprotected directories, they could be maliciously modified to become Trojans destroying user files or otherwise compromising 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 AdministratorDCSW-1Checks
Check local initialization files for any executed world-writable programs or scripts.Procedure:
# more /<usershomedirectory>/.*
# ls -al <program or script>
If any local initialization file executes a world-writable program or script, this is a finding.
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.
V-4089
No Change
Findings ID: | GEN001660 | Rule ID: | SV-27209r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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
Check the run control scripts' ownership.Procedure:
# ls -lL /etc/rc*
If any run control script is not owned by root or bin, this is a finding.
Fix
Change the ownership of the run control script(s) with incorrect ownership.# chown root <run control script>
V-4090
No Change
Findings ID: | GEN001680 | Rule ID: | SV-27216r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
If system start-up files do not have a group owner of a system group, the files may be modified by malicious users or intruders.System AdministratorECLP-1Checks
Check run control scripts' group ownership.Procedure:
# ls -lL /etc/rc*
If any run control script is not group-owned by sys, bin, other, or system, this is a finding.
Fix
Change the group ownership of the run control script(s) with incorrect group ownership.Procedure:
# chgrp sys <run control script>
V-4091
No Change
Findings ID: | GEN001700 | Rule ID: | SV-27221r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
System start-up files executing programs owned by other than root (or another privileged user) or an application indicate the system may have been compromised.System AdministratorDCSL-1
Checks
Check the ownership of any files executed from system startup scripts. If any of these files are not owned by root, bin, sys, or other, this is a finding.Fix
Change the ownership of the file executed from system startup scripts to root, bin, sys, or other.# chown root <executed file>
V-4246
No Change
Findings ID: | GEN008620 | Rule ID: | SV-38836r1_rule | Severity: | medium | CCI: | CCI-000213 |
---|
Discussion
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-1Checks
Ask the SA if a password has been given to the Service processors ADMIN account. If a password has not been assigned to the service processor, this is a finding.Fix
Access the system's service processor. Set a supervisor/administrator password if one has not been set. Disable a user-level password if one has been set.
V-4247
No Change
Findings ID: | GEN008640 | Rule ID: | SV-38837r1_rule | Severity: | high | CCI: | CCI-000366 |
---|
Discussion
Malicious users with removable boot media can gain access to a system configured to use removable media as the boot loader.System AdministratorECSC-1Checks
Check the servers boot lists for the normal, service, both, or prevboot modes.# bootlist -m <mode> -o
Ensure hdisk{x} is the only devices listed. If boot devices, such as cd{x}, fd{x}. rmt{x}, ent{x} are used, this is a finding.
Fix
Configure the system to use a bootloader installed on fixed media.# bootlist -m normal hdisk0
# bootlist -m service hdisk0
V-4255
No Change
Findings ID: | GEN008680 | Rule ID: | SV-4255r2_rule | Severity: | high | CCI: | CCI-001208 |
---|
Discussion
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-1Checks
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
Store the system boot media in a secure container when not in use.
V-4269
No Change
Findings ID: | GEN000290 | Rule ID: | SV-38767r1_rule | Severity: | medium | CCI: | CCI-000012 |
---|
Discussion
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-1Checks
Check the system for unnecessary user accounts.Procedure:
# more /etc/passwd
Some examples of unnecessary accounts includes guest, uucp, games, news, gopher, ftp, and lp. If any unnecessary accounts are found, this is a finding.
Fix
Remove all unnecessary accounts, such as games, from the /etc/passwd file before connecting a system to the network. Other accounts, such as news and gopher, that are associated with a service not in use should also be removed.# rmuser -p <username>
V-4273
No Change
Findings ID: | GEN006260 | Rule ID: | SV-39250r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
Excessive permissions on the hosts.nntp file may allow unauthorized modification which could lead to Denial of Service to authorized users or provide access to unauthorized users.System AdministratorECLP-1Checks
Check /etc/news/hosts.nntp permissions.# find / -name hosts.nntp
# ls -lL < hosts.nntp file >
If /etc/news/hosts.nntp has a mode more permissive than 0600, this is a finding.
Fix
Change the mode of the hosts.nntp file to 0600.# chmod 0600 < hosts.nntp file>
V-4274
No Change
Findings ID: | GEN006280 | Rule ID: | SV-39252r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check /etc/news/hosts.nntp.nolimit permissions.# find / -name hosts.nntp.nolimit
# ls -lL < hosts.nntp.nolimit file >
If hosts.nntp.nolimit has a mode more permissive than 0600, this is a finding.
Fix
Change the mode of hosts.nntp.nolimit to 0600.# chmod 0600 < hosts.nntp.nolimit file>
V-4275
No Change
Findings ID: | GEN006300 | Rule ID: | SV-39255r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check /etc/news/nnrp.access permissions.# find / -name nnrp.access
# ls -lL < nnrp.access >
If /etc/news/nnrp.access has a mode more permissive than 0600, this is a finding.
Fix
Change the mode of the nnrp.access file to 0600.# chmod 0600 < nnrp.access >
V-4276
No Change
Findings ID: | GEN006320 | Rule ID: | SV-39260r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check /etc/news/passwd.nntp permissions.# find / -name passwd.nntp
# ls -lL < passwd.nntp >
If passwd.nntp has a mode more permissive than 0600, this is a finding.
Fix
Change the mode of the passwd.nntp file.# chmod 0600 < passwd.nntp >
V-4277
No Change
Findings ID: | GEN006340 | Rule ID: | SV-4277r2_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
If critical system files are not owned by a privileged user, system integrity could be compromised.System AdministratorECLP-1Checks
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
Change the ownership of the files in /etc/news to root or news.Procedure:
# chown root /etc/news/*
V-4278
No Change
Findings ID: | GEN006360 | Rule ID: | SV-40837r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
If critical system files do not have a privileged group owner, system integrity could be compromised.System AdministratorECLP-1Checks
Check /etc/news files group ownership.Procedure:
# ls -al /etc/news
If /etc/news files are not group-owned by system or news, this is a finding.
Fix
Change the group owner of the files in /etc/news to system or news.Procedure:
# chgrp news /etc/news/*
V-4284
No Change
Findings ID: | GEN000000-AIX00040 | Rule ID: | SV-4284r2_rule | Severity: | medium | CCI: | CCI-000032 |
---|
Discussion
The AIX securetcpip command disables insecure network utilities, such as rcp, rlogin, rlogind, rsh, rshd, tftp, tftpd, and trpt/d. These services increase the attack surface of the system.System AdministratorECSC-1Checks
The securetcpip command is in /etc. If it is not there, this is a finding.Perform:
more /etc/security/config
If the stanza below is not there, this is a finding.
tcpip:
netrc = ftp, rexec
The stanza indicates the securetcpip command, which disables all the unsafe tcpip commands, (e.g., rsh, rlogin, tftp) has been executed.
Fix
Ensure secure tcp/ip has been invoked before allowing operations on the system.
V-4287
No Change
Findings ID: | GEN000000-AIX00060 | Rule ID: | SV-4287r2_rule | Severity: | medium | CCI: | CCI-001298 |
---|
Discussion
If a baseline of files with the TCB bit set is not kept and checked weekly, the system could be compromised without the knowledge of any authority.System AdministratorDCSL-1Checks
Perform the following command with no parameters to ensure the system is in trusted mode.# /bin/tcbck
If TCB is not installed, the output will show an error code of 3001-101 and/or a text message indicating TCB is not installed. If the output from the command indicates it is not in trusted mode, this is not reviewed. Otherwise, check the root crontab to verify tcbck is executed weekly. If it is not in the crontab, ask the SA if the check is run manually and to see the results of the check.
Fix
Add tcbck command as a weekly cronjob with the output sent to the SA.
V-4295
No Change
Findings ID: | GEN005500 | Rule ID: | SV-40862r2_rule | Severity: | high | CCI: | CCI-001436 |
---|
Discussion
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 AdministratorChecks
Examine the sshd configuration file.# cat /etc/ssh/sshd_config | grep -i "Protocol 2"
If the value of "Protocol" is not set to 2, or is commented out, this is a finding.
Fix
Edit the configuration file and modify the Protocol line.Protocol 2
Restart sshd:
/sbin/init.d/secsh stop
/sbin/init.d/secsh start
V-4298
No Change
Findings ID: | GEN001000 | Rule ID: | SV-27149r1_rule | Severity: | medium | CCI: | CCI-000070 |
---|
Discussion
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-1Checks
Check /etc/security/login.cfg# more /etc/security/login.cfg
If an alternate console is defined, this is a finding.
Fix
Edit /etc/security/login.cfg and remove the alternate console definition.
V-4301
No Change
Findings ID: | GEN000240 | Rule ID: | SV-38666r1_rule | Severity: | medium | CCI: | CCI-001492 |
---|
Discussion
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 synchronizing 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 (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
Verify if NTP running.# lssrc -s xntpd
or
# ps -ef | egrep "xntpd|ntpd"
or
# ntpq -p
Verify xntpd is started at boot time and scheduled to run.
#grep xntpd /etc/rc.tcpip | grep -v \#
If NTP is running use the following command.
# more /etc/ntp.conf and
# ntpq -p
Confirm the servers and peers or multicastclient (as applicable) are local or an authoritative U.S. DoD source.
If a non-local/non-authoritative (U.S. DoD source) time-server is used, this is a finding.
Fix
Use a local authoritative time server that synchronizes to an authorized DoD time source. Ensure all systems in the facility feed from one or more local time servers feeding from the authoritative time server.View the (x)ntp/(x)ntpd man page(s).
# man xntpd
Create/edit the /etc/ntp.conf file, delete any non-local and/or non-US/DoD sources and insert the local or an authoritative US/DoD source.
Start or restart the NTP service.
# refresh -s xntpd
OR
# stopsrc -s xntpd
# startsrc -s xntpd
V-4304
No Change
Findings ID: | GEN003640 | Rule ID: | SV-38909r1_rule | Severity: | medium | CCI: | CCI-000553 |
---|
Discussion
File system journaling, or logging, can allow reconstruction of file system data after a system crash, thus, 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 which also satisfy this requirement.System AdministratorECAR-1, ECAR-2, ECAR-3Checks
Logging should be enabled for those types of files systems that do not turn on logging by default.Procedure:
# mount
#lsfs
JFS, JFS2, 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 system types, if the root file system does not have the logging option, this is a finding. If the nolog option or the log=NULL option is set on the root file system, this is a finding.
Fix
Implement file system journaling for the root file system, or use a file system using other mechanisms to ensure consistency. If the root file system supports journaling, enable it. If the file system does not support journaling or another mechanism to ensure consistency, a migration to a different file system will be necessary.
V-4321
No Change
Findings ID: | GEN006060 | Rule ID: | SV-4321r2_rule | Severity: | medium | CCI: | CCI-001436 |
---|
Discussion
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-1Checks
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
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 utility should also be removed or not installed if there is no functional requirement.
V-4357
No Change
Findings ID: | GEN002860 | Rule ID: | SV-4357r2_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
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-1Checks
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 still 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
Configure a cron job or other automated process to rotate the audit logs on a daily basis.
V-4358
No Change
Findings ID: | GEN003200 | Rule ID: | SV-27360r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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
Check the mode of the cron.deny file.# ls -lL /var/adm/cron/cron.deny
If the cron.deny file is more permissive than 0600, this is a finding.
Fix
Change the mode of the cron.deny file.# chmod 0600 /var/adm/cron/cron.deny
V-4360
No Change
Findings ID: | GEN003220 | Rule ID: | SV-27364r1_rule | Severity: | low | CCI: | CCI-000225 |
---|
Discussion
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 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-2Checks
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.# ls -lL /var/spool/cron/crontabs
# 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 value more permissive than 077, this is a finding.
Fix
Edit cron script files and modify the umask to 077.
V-4361
No Change
Findings ID: | GEN003240 | Rule ID: | SV-27367r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
# ls -lL /var/adm/cron/cron.allowIf the cron.allow file is not owned by root, sys, or bin, this is a finding.
Fix
# chown root /var/adm/cron/cron.allow
V-4364
No Change
Findings ID: | GEN003400 | Rule ID: | SV-38907r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the mode of the at directory.# ls -lLd /var/spool/cron/atjobs
If the directory mode is more permissive than 0755, this is a finding.
Fix
Change the mode of the "at" directory to 0755.Procedure:
# chmod 0755 < at directory >
V-4365
No Change
Findings ID: | GEN003420 | Rule ID: | SV-39350r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
If the owner of the at directory is not root, bin, sys, daemon, or cron unauthorized users could be allowed to view or edit files containing sensitive information within the directory.System AdministratorECLP-1Checks
Check the ownership of the at directory.Procedure:
# ls -ld /var/spool/cron/atjobs
If the directory is not owned by root, bin, sys, daemon, or cron, this is a finding.
Fix
Change the owner of the at directory to root, bin, sys, daemon, or cron.Procedure:
# chown bin /var/spool/cron/atjobs
V-4366
No Change
Findings ID: | GEN003440 | Rule ID: | SV-4366r2_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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 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-2Checks
Determine what "at" jobs exist on the system.Procedure:
# ls /var/spool/cron/atjobs /var/spool/atjobs
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
Edit "at" jobs or referenced scripts to remove umask commands setting umask to a value less restrictive than 077.
V-4367
No Change
Findings ID: | GEN003460 | Rule ID: | SV-27393r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
# ls -lL /var/adm/cron/at.allowIf the at.allow file is not owned by root, sys, or bin, this is a finding.
Fix
Change the owner of the at.allow file.# chown root /var/adm/cron/at.allow
V-4368
No Change
Findings ID: | GEN003480 | Rule ID: | SV-27397r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
# ls -lL /var/adm/cron/at.denyIf the at.deny file is not owned by root, sys, or bin, this is a finding.
Fix
Change the owner of the at.deny file.# chown root /var/adm/cron/at.deny
V-4369
No Change
Findings ID: | GEN003960 | Rule ID: | SV-28393r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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 possibly leading to system and network compromise.System AdministratorECLP-1Checks
# ls -lL /usr/bin/tracerouteIf the traceroute command is not owned by root, this is a finding.
Fix
Change the owner of the traceroute command to root.Example:
# chown root /usr/bin/traceroute
V-4370
No Change
Findings ID: | GEN003980 | Rule ID: | SV-28397r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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 possibly leading to system and network compromise.System AdministratorECLP-1Checks
Check the group ownership of the traceroute file.Procedure:
# ls -lL /usr/bin/traceroute
If the traceroute command is not group-owned by sys, bin, or system, this is a finding.
Fix
Change the group owner of the traceroute command to sys, bin, or system.Procedure:
# chgrp system /usr/bin/traceroute
V-4371
No Change
Findings ID: | GEN004000 | Rule ID: | SV-28400r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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 possibly leading to system and network compromise.System AdministratorECLP-1Checks
# ls -lL /usr/bin/tracerouteIf the traceroute command has a mode more permissive than 0700, this is a finding.
Fix
Change the mode of the traceroute command.# chmod 0700 /usr/bin/traceroute
V-4382
No Change
Findings ID: | GEN004220 | Rule ID: | SV-4382r2_rule | Severity: | high | CCI: | CCI-000225 |
---|
Discussion
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 AdministratorECLP-1
Checks
Look in the root account home directory for a .netscape or a .mozilla directory. If none exists, this is not a finding. If there is one, verify with the root users and the IAO what the intent of the browsing is. Some evidence may be obtained by using the browser to view cached pages under the .netscape directory.Fix
Enforce policy requiring administrative accounts use web browsers only for local service administration.
V-4384
No Change
Findings ID: | GEN004560 | Rule ID: | SV-39164r1_rule | Severity: | low | CCI: | CCI-000366 |
---|
Discussion
The version of the SMTP service can be used by attackers to plan an attack based on vulnerabilities present in the specific version.System AdministratorECSC-1Checks
Check for the Sendmail version being displayed in the greeting.# telnet localhost 25
If a version number is displayed, this is a finding.
Fix
Ensure Sendmail or its equivalent has been configured to mask the version information. If necessary, change the O SmtpGreetingMessage line in the /etc/sendmail.cf file.O SmtpGreetingMessage=$j Sendmail $v/$Z; $b
Change it to:
O SmtpGreetingMessage= Mail Server Ready ; $b
V-4385
No Change
Findings ID: | GEN004580 | Rule ID: | SV-4385r2_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
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 AdministratorECSC-1Checks
Search for any .forward files on the system.# find / -name .forward -print
This is considered a finding if any .forward files are found on the system.
Fix
Remove .forward files from the system.
V-4387
No Change
Findings ID: | GEN005000 | Rule ID: | SV-4387r2_rule | Severity: | high | CCI: | CCI-000225 |
---|
Discussion
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 AdministratorECCD-1, ECCD-2Checks
Check the shell for the anonymous FTP account.Procedure:
# grep "^ftp" /etc/passwd
This is a finding if the seventh field is empty (the entry ends with a ':') or if the seventh field does not contain one of the following.
/bin/false
/dev/null
/usr/bin/false
/bin/true
/sbin/nologin
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.
V-4392
No Change
Findings ID: | GEN005380 | Rule ID: | SV-4392r2_rule | Severity: | medium | CCI: | CCI-001208 |
---|
Discussion
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-1Checks
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
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.
V-4393
No Change
Findings ID: | GEN005400 | Rule ID: | SV-4393r2_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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 AdministratorECLP-1Checks
Check /etc/syslog.conf ownership.# ls -lL /etc/syslog.conf
If /etc/syslog.conf is not owned by root, this is a finding.
Fix
Use the chown command to set the owner to root.# chown root /etc/syslog.conf
V-4394
No Change
Findings ID: | GEN005420 | Rule ID: | SV-40364r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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 AdministratorECLP-1Checks
Check /etc/syslog.conf group ownership.Procedure:
# ls -lL /etc/syslog.conf
If /etc/syslog.conf is not group-owned by sys, bin, or system, this is a finding.
Fix
Change the group owner of the /etc/syslog.conf file to bin, sys, or system.Procedure:
# chgrp system /etc/syslog.conf
V-4395
No Change
Findings ID: | GEN005460 | Rule ID: | SV-4395r2_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
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.trueSystem AdministratorInformation Assurance OfficerECSC-1Checks
Examine the syslog.conf file for any references to remote log hosts.# grep -v "^#" /etc/syslog.conf | grep '@'
Destination locations beginning with an @ represent log hosts. If the log host name is a local alias, such as log host, 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
Remove, replace, or document the referenced undocumented log host.
V-4397
No Change
Findings ID: | GEN005560 | Rule ID: | SV-39217r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
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-1Checks
Check the system for an IPv4 default route.Procedure:
# netstat -r |grep default
If a default route is not defined, this is a finding.
Fix
Set a default gateway for IPv4.# smitty route
OR
# route add 0 < ip address of gateway >
V-4398
No Change
Findings ID: | GEN005580 | Rule ID: | SV-4398r2_rule | Severity: | medium | CCI: | CCI-001208 |
---|
Discussion
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 AdministratorDCSP-1Checks
Ask the SA if the system is a designated 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
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.
V-4399
No Change
Findings ID: | GEN006380 | Rule ID: | SV-4399r2_rule | Severity: | high | CCI: | CCI-001436 |
---|
Discussion
Implementing 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-1Checks
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
Configure the system to not use UDP for NIS and NIS+. Consult vendor documentation for the required procedure.
V-4427
No Change
Findings ID: | GEN002020 | Rule ID: | SV-4427r2_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
If these files are not properly configured, they could allow malicious access by unknown malicious users from untrusted hosts who could compromise the system.G614. The only allowable use of a’ +’ character in a hosts.equiv and .rhosts files is to allow NIS+ netgroups access to the system.System AdministratorECCD-1, ECCD-2Checks
Locate and examine all .rhosts, .shosts, hosts.equiv, and shosts.equiv 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
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.
V-4428
No Change
Findings ID: | GEN002060 | Rule ID: | SV-39502r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
# find / -type f -name .rhosts# ls -alL /<directorylocation>/.rhosts
# find / -type f -name .shosts
# ls -alL /<directorylocation>/.shosts
# find / -type f -name hosts.equiv
# ls -lL /<directorylocation>/hosts.equiv
# find / -type f -name shosts.equiv
# ls -lL /<directorylocation>/shosts.equiv
If the .rhosts, .shosts, hosts.equiv, or shosts.equiv files have permissions greater than 700, this is a finding.
Fix
Ensure the permission for these files is set at 700 or less and the owner is the owner of the home directory that it is in. These files, outside of home directories (other than hosts.equiv which is in /etc and owned by root), have no meaning.
V-4430
No Change
Findings ID: | GEN003260 | Rule ID: | SV-27372r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
Cron daemon control files restrict the scheduling of automated tasks and must be protected.System AdministratorECLP-1
Checks
# ls -lL /var/adm/cron/cron.denyIf the cron.deny file is not owned by root, sys, or bin, this is a finding.
Fix
# chown root /var/adm/cron/cron.deny
V-4687
No Change
Findings ID: | GEN003820 | Rule ID: | SV-27434r1_rule | Severity: | high | CCI: | CCI-000068 |
---|
Discussion
The rshd process provides a typically unencrypted, host-authenticated remote access service. SSH should be used in place of this service.System AdministratorInformation Assurance OfficerEBRU-1
Checks
# grep -v "^#" /etc/inetd.conf |grep rshdIf rshd is found to be enabled, this is a finding.
Fix
Edit /etc/inetd.conf and comment out the rshd service. Restart the inetd service.
V-4688
No Change
Findings ID: | GEN003840 | Rule ID: | SV-38878r1_rule | Severity: | high | CCI: | CCI-001435 |
---|
Discussion
The rexecd process provides a typically unencrypted, host-authenticated remote access service. SSH should be used in place of this service.trueInformation Assurance OfficerSystem AdministratorECSC-1Checks
# grep -v "^#" /etc/inetd.conf |grep rexecIf any results are returned, this is a finding.
Fix
Edit /etc/inetd.conf and comment out the line for the rexec service.Refresh the inetd daemon.
# refresh -s inetd
V-4689
No Change
Findings ID: | GEN004600 | Rule ID: | SV-38917r1_rule | Severity: | high | CCI: | CCI-001230 |
---|
Discussion
The SMTP service version on the system must be current to avoid exposing vulnerabilities present in unpatched versions.System AdministratorVIVM-1Checks
Determine the version of the SMTP service software.Locate the sendmail daemon.
Procedure:
# find / -name sendmail
Obtain version information for the Sendmail daemon.
Procedure:
# what < file location >
OR
# strings < file location > | grep version
OR
# echo \$Z | sendmail -d0
Version 8.14.5 is the latest released version.
If the Sendmail version is not at least 8.14.5 or the vendor's latest version, this is a finding.
Fix
Obtain and install a newer version of Sendmail from the operating system vendor or from http://www.sendmail.org or ftp://ftp.cs.berkeley.edu/ucb/sendmail.
V-4690
No Change
Findings ID: | GEN004620 | Rule ID: | SV-4690r2_rule | Severity: | high | CCI: | CCI-000366 |
---|
Discussion
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-1Checks
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, this is a finding.
If telnet is unavailable for testing, check the version of sendmail installed on the system.
# echo \$Z | /usr/sbin/sendmail -bt -d0
If the sendmail reported version is less than 8.6, this is a finding.
Fix
Obtain and install a more recent version of Sendmail, which does not implement the DEBUG feature.
V-4691
No Change
Findings ID: | GEN004640 | Rule ID: | SV-4691r2_rule | Severity: | high | CCI: | CCI-001230 |
---|
Discussion
A common configuration for older Mail Transfer Agents (MTAs) includes 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 decode or 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-1Checks
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
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 "newaliases" command. For more information on mail aliases, refer to the man page for aliases. Disabled aliases would be similar to the examples below:# decode: |/usr/bin/uudecode
# uudecode: |/usr/bin/uuencode -d
V-4692
No Change
Findings ID: | GEN004660 | Rule ID: | SV-28402r1_rule | Severity: | low | CCI: | CCI-000366 |
---|
Discussion
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-1Checks
Perform the following to determine if EXPN is disabled:# telnet localhost 25
expn root
If the command does not return a 500 error code of command unrecognized, this is a finding.
OR
Locate the sendmail.cf configuration file by:
# find / -name sendmail.cf -print
# grep -v "^#" <sendmail.cf location> |grep -i privacyoptions
The O PrivacyOptions should have the noexpn or the goaway option (covering both noexpn and novrfy).
If the EXPN command is not disabled, this is a finding.
Fix
Edit the sendmail.cf file and add or edit the following line:O PrivacyOptions=goaway
Restart the Sendmail service.
V-4693
No Change
Findings ID: | GEN004680 | Rule ID: | SV-39171r1_rule | Severity: | low | CCI: | CCI-000366 |
---|
Discussion
The VRFY (Verify) 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-1Checks
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
Locate the sendmail.cf configuration file.
Procedure:
# find / -name sendmail.cf -print # grep -v "^#" |grep -i vrfy
Ensure 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
If you are running Sendmail, add the line Opnovrfy to your Sendmail configuration file, usually located in /etc/sendmail.cf. For other mail servers, contact the vendor for information on how to disable the verify command. Newer versions of Sendmail are available at http://www.sendmail.org or from ftp://ftp.cs.berkeley.edu/ucb/sendmail.
V-4694
No Change
Findings ID: | GEN004700 | Rule ID: | SV-4694r2_rule | Severity: | low | CCI: | CCI-000366 |
---|
Discussion
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-1Checks
Locate the sendmail.cf configuration file and check for wiz configuration.Procedure:
# find / -name sendmail.cf -print
# grep -v "^#" <sendmail.cf location> |grep -i wiz
If an entry is found for wiz, this is a finding.
Fix
If the WIZ command is enabled on Sendmail, it should be disabled by adding this line to the sendmail.cf configuration file (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.
V-4695
No Change
Findings ID: | GEN005140 | Rule ID: | SV-39193r1_rule | Severity: | high | CCI: | CCI-000225 |
---|
Discussion
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.System AdministratorInformation Assurance OfficerDCSW-1Checks
Determine if the TFTP daemon is active.# grep -v "^#" /etc/inetd.conf |grep tftp
If TFTP is found enabled, it is a finding if it is not documented using site-defined procedures.
Fix
Disable the TFTP daemon.Edit /etc/inetd.conf and comment out the tftp line.
Restart the inetd service.
# refresh -s inetd
V-4696
No Change
Findings ID: | GEN005280 | Rule ID: | SV-28427r1_rule | Severity: | medium | CCI: | CCI-001436 |
---|
Discussion
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-1Checks
# grep uucp /etc/inetd.confIf uucp is found enabled, this is a finding.
Fix
Edit /etc/inetd.conf and comment out the uucp service. Restart the inetd service.
V-4697
No Change
Findings ID: | GEN005200 | Rule ID: | SV-4697r2_rule | Severity: | high | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
If X Windows 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 that can 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
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.
V-4701
No Change
Findings ID: | GEN003860 | Rule ID: | SV-27440r1_rule | Severity: | low | CCI: | CCI-001551 |
---|
Discussion
The finger service provides information about the system's users to network clients. This information could expose information that could be used in subsequent attacks.System AdministratorDCPP-1
Checks
# grep -v "^#" /etc/inetd.conf |grep fingerIf the finger service is not disabled, this is a finding.
Fix
Edit /etc/inetd.conf and comment out the finger service line. Restart the inetd service.
V-4702
No Change
Findings ID: | GEN004840 | Rule ID: | SV-4702r2_rule | Severity: | medium | CCI: | CCI-000787 |
---|
Discussion
Anonymous FTP is a public data service which is only permitted in a server capacity when located on the DMZ network.System AdministratorInformation Assurance OfficerECSC-1Checks
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 [email protected]). 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
Move the system to a DMZ network.
V-11940
Updated
Findings ID: | GEN000100 | Rule ID: | SV-27052r |
Severity: | high | CCI: | CCI-001230 |
---|
Discussion
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 providing security patches for the unsupported product is procured from the vendor, this finding may be downgraded to a CAT III.System AdministratorChecks
# oslevelVendor
AIX
AIX 5.2 End of support 30 April 2009
AIX 5.1 End of support 1 April 2006
If the release is not supported, this is a finding.
Fix
Upgrade to a supported version of the operating system.
V-11941
No Change
Findings ID: | GEN000140 | Rule ID: | SV-38784r1_rule | Severity: | medium | CCI: | CCI-000293 |
---|
Discussion
A file integrity baseline is a collection of file metadata which 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 AdministratorDCSW-1Checks
Determine if a file integrity baseline, which includes cryptographic hashes, has been created and maintained for the system. If no file integrity baseline exists for the system, this is a finding. If the file integrity baseline contains no cryptographic hashes, this is a finding. If the file integrity baseline is not maintained (has not been updated to be consistent with the latest approved system configuration changes), this is a finding.Fix
Create a file integrity baseline, including cryptographic hashes, for the system.# find / -depth -print | tee Baseline
Open the above file and either manually execute md5sum, csum, or the chksum command on each file. Alternatively, write a script to perform the above. NOTE: For security purposes, "md5sum" is preferred over "chksum". The md5sum command can be loaded from the Linux Tool Kit for AIX.
Alternatively, OpenSSL can be used to create hashes.
#openssl dgst -md5 < file >
V-11945
No Change
Findings ID: | GEN000220 | Rule ID: | SV-28610r2_rule | Severity: | medium | CCI: | CCI-001069 |
---|
Discussion
Changes in system libraries and binaries 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
Determine if there is a cron job, scheduled to run weekly or more frequently, to run the file integrity tool to check for unauthorized system libraries or binaries, or unauthorized modification to authorized system libraries or binaries.Procedure:
# crontab -l
If there is no cron job meeting these requirements, this is a finding.
NOTE: The frequency may be increased to daily, if necessary, in accordance with the contingency plan.
Fix
Create a cron job, scheduled to run weekly or more frequently, to run the file integrity tool to check for unauthorized system libraries or binaries, or unauthorized modification to authorized system libraries or binaries.NOTE: The frequency may be increased to daily, if necessary, in accordance with the contingency plan.
V-11946
No Change
Findings ID: | GEN000340 | Rule ID: | SV-38669r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
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
Check the UID assignments of all accounts.# more /etc/passwd
Confirm all accounts with a UID of 128 and below are used by a system account. If a UID reserved for system accounts (0-128) is used by a non-system account, this is a finding.
Fix
Using the usermod command, change the UID numbers for non-system accounts with reserved UIDs (those less or equal to 128).# usermod -u <uid> login
Alternatively, smit can be used for this same purpose.
#smitty users
V-11947
No Change
Findings ID: | GEN000580 | Rule ID: | SV-38936r2_rule | Severity: | medium | CCI: | CCI-000205 |
---|
Discussion
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 AdministratorChecks
Check the system password length setting.# /usr/sbin/lsuser -a minlen ALL
If minlen is not set to 15 or more, this is a finding.
Fix
Change the minimum password length to 15 or more.# chsec -f /etc/security/user -s default -a minlen=15
# chuser minlen=15 <user id>
V-11973
No Change
Findings ID: | GEN000640 | Rule ID: | SV-39503r1_rule | Severity: | medium | CCI: | CCI-001619 |
---|
Discussion
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-2Checks
Fix
Use the chsec command to set the minother setting to 1.# chsec -f /etc/security/user -s default -a minother=1
# chuser minother=1 < user id >
V-11975
No Change
Findings ID: | GEN000680 | Rule ID: | SV-38675r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
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-2Checks
Check the maxrepeats setting.Procedure:
# grep -i maxrepeats /etc/security/user
OR
# lsuser -a maxrepeats ALL
If the maxrepeats setting is greater than 3, this is a finding.
Fix
Use the chsec command to set maxrepeats to 3.# chsec -f /etc/security/user -s default -a maxrepeats=3
# chuser maxrepeats=3 < user id >
V-11976
No Change
Findings ID: | GEN000700 | Rule ID: | SV-38939r1_rule | Severity: | medium | CCI: | CCI-000180 |
---|
Discussion
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 AdministratorIAIA-1, IAIA-2Checks
Fix
Use the chsec command to set the maxage field to 8 for each user.# chsec -f /etc/security/user -s default -a maxage=8
# chuser maxage=8 < user id >
V-11977
No Change
Findings ID: | GEN000740 | Rule ID: | SV-38676r1_rule | Severity: | medium | CCI: | CCI-000199 |
---|
Discussion
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-2Checks
NOTE: This will always require a manual review. This is a local policy issue/question. 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. If the SA indicates passwords for automated processing accounts are not changed once per year, this is a finding.Procedure:
Go to last password change date for the system account.
# grep -p <account_name> /etc/security/passwd | grep lastupdate
To examine the time a password was last changed, the following perl script has been provided. Put the lastupdate value in the <lastupdate>.
#perl -e 'use POSIX; print strftime("%c\n" , localtime(<lastupdate>));'
Fix
Implement or establish procedures to change the passwords of automated processing accounts at least once per year.#passwd account
V-11979
No Change
Findings ID: | GEN001020 | Rule ID: | SV-40787r1_rule | Severity: | medium | CCI: | CCI-000770 |
---|
Discussion
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 AdministratorECPA-1Checks
Check if the root is used for direct logins.Procedure: # last root | grep -v reboot
If any direct login records for root exist, this is a finding.
Fix
Enforce policy requiring all root account access is attained by first logging into a user account and then becoming root (using su, for example).
V-11980
No Change
Findings ID: | GEN001060 | Rule ID: | SV-27154r1_rule | Severity: | medium | CCI: | CCI-000126 |
---|
Discussion
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 AdministratorECAR-1, ECAR-2, ECAR-3Checks
Check the following log files to determine if access to the root account is being logged. Try to su - and enter an incorrect password.# more /var/adm/sulog
If root login accounts are not being logged, this is a finding.
Fix
Troubleshoot the system logging configuration to provide for logging of root account login attempts.
V-11981
No Change
Findings ID: | GEN001720 | Rule ID: | SV-38882r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check global initialization files permissions:# ls -l /etc/.login /etc/profile /etc/bashrc /etc/environment /etc/security/environ /etc/security/.profile /etc/csh.login /etc/csh.cshrc
If global initialization files are more permissive than 0644, this is a finding.
Fix
Change the mode of the global initialization file(s) to 0444.# chmod 0444 <global initialization file>
V-11982
No Change
Findings ID: | GEN001740 | Rule ID: | SV-38884r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the ownership of global initialization files.Procedure:
# ls -lL /etc/.login /etc/profile /etc/bashrc /etc/environment /etc/security/environ /etc/security/.profile /etc/csh.login /etc/csh.cshrc
If any global initialization file is not owned by root, this is a finding.
Fix
Change the ownership of global initialization files with incorrect ownership.Procedure:
# chown bin <global initialization files>
V-11983
No Change
Findings ID: | GEN001760 | Rule ID: | SV-38892r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the group ownership of global initialization files.Procedure:
# ls -lL /etc/.login /etc/profile /etc/bashrc /etc/environment /etc/security/environ /etc/security/.profile /etc/csh.login /etc/csh.cshrc
If any global initialization file is not group-owned by sys, bin, system, or security, this is a finding.
Fix
Change the group ownership of the global initialization file(s) with incorrect group ownership.Procedure:
# chgrp system <global initialization file>
V-11984
No Change
Findings ID: | GEN001820 | Rule ID: | SV-38737r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check skeleton files ownership.Procedure:
# ls -l /etc/security/.profile /etc/security/mkuser.sys
If a skeleton file is not owned by root or bin, this is a finding.
Fix
Change the ownership of skeleton files with incorrect mode.# chown root /etc/security/.profile /etc/security/mkuser.sys
V-11985
Updated
Findings ID: | GEN001840 | Rule ID: | SV-12486r |
Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
The executable search path (typically the PATH environment variable) contains a list of directories for the shell to search to find executables.Checks
Check the global initialization files' executable search paths.Procedure:
# grep -i PATH /etc/profile /etc/bashrc /etc/csh.login /etc/csh.cshrc /etc/environment /etc/.login /etc/security/environ
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
Fix
Edit the global initialization file(s) with PATH variables containing relative pathsEdit the global initialization file(s) and remove any empty entry that is defined.
V-11986
Updated
Findings ID: | GEN001900 | Rule ID: | SV-12487r |
Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
The executable search path (typically the PATH environment variable) contains a list of directories for the shell to search to find executables.Checks
NOTE: The following must be done in the BASH shell.Examine the PATH variable contained in any user's local initialization files
# cat /etc/passwd | cut -f 1,1 -d ":" | xargs -n1 -IUSER sh -c 'grep -i PATH ~USER/.*'
The PATH variable is a colon-delimited directory list.
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
Fix
Edit the local initialization file(s) and remove the relative path entrEdit the local initialization file(s) and remove any empty entry that is defined.
V-11987
No Change
Findings ID: | GEN001980 | Rule ID: | SV-38740r2_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
A plus (+) in system accounts files causes the system to lookup the specified entry using NIS or LDAP. If the system is not using NIS or LDAP, no such entries should exist.System AdministratorChecks
Check system configuration files for plus (+) entries.Procedure:
# find / -name .rhosts
# cat /<directorylocation>/.rhosts | grep -v "^#" | grep "\+"
# find / -name .shosts
# cat /<directorylocation>/.shosts | grep -v "^#" | grep "\+"
# find / -name hosts.equiv
# cat /<directorylocation>/hosts.equiv | grep -v "^#" | grep "\+"
# find / -name shosts.equiv
# cat /<directorylocation>/shosts.equiv | grep -v "^#" | grep "\+"
# cat /etc/passwd | grep -v "^#" | grep "\+"
# cat /etc/security/passwd | grep -v "^#" | grep "\+"
# cat /etc/group | grep -v "^#" | grep "\+"
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 or LDAP netgroups, this is a finding.
Fix
Edit the .rhosts, .shosts, hosts.equiv, shosts.equiv, /etc/passwd, /etc/security/passwd, and/or /etc/group files and remove entries containing a plus (+).
V-11988
No Change
Findings ID: | GEN002040 | Rule ID: | SV-12489r2_rule | Severity: | high | CCI: | CCI-000366 |
---|
Discussion
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.System AdministratorInformation Assurance OfficerECCD-1, ECCD-2Checks
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, this is a finding.
Fix
Remove the .rhosts, .shosts, hosts.equiv, and/or shosts.equiv files.
V-11989
No Change
Findings ID: | GEN002100 | Rule ID: | SV-38845r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
The .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-2Checks
Check the PAM configuration for rhosts_auth.Procedure:
# grep rhosts_auth /etc/pam.conf |grep -v \#
If a rhosts_auth entry is found, this is a finding.
Fix
Edit /etc/pam.conf and remove the reference(s) to the rhosts_auth module.
V-11990
No Change
Findings ID: | GEN002540 | Rule ID: | SV-40066r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
If a public directory has the sticky bit set and is not group-owned by a system 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
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 system, sys, bin, or an application group, this is a finding.
Fix
Change the group ownership of the public directory.Procedure:
# chgrp system /tmp
(Replace system with a different system group and/or /tmp with a different public directory as necessary.)
V-11994
No Change
Findings ID: | GEN003040 | Rule ID: | SV-27333r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
To protect the integrity of scheduled system jobs and prevent malicious modification to these jobs, crontab files must be secured.System AdministratorDCSL-1Checks
List all crontabs on the system.# ls -lL /var/spool/cron/crontabs/
If any crontab is not owned by root or the creating user, this is a finding.
Fix
Change the crontab owner to root or the crontab creator.# chown root <crontab file>
V-11995
No Change
Findings ID: | GEN003060 | Rule ID: | SV-27336r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
To centralize the management of privileged account crontabs, of the default system accounts, only root may have a crontab.System AdministratorECPA-1Checks
Check the cron.allow and cron.deny files for the system.# more /var/adm/cron/cron.allow
# more /var/adm/cron/cron.deny
If a default system account (such as bin, sys, adm, or others) is listed in the cron.allow file, or not listed in the cron.deny file if no cron.allow file exists, this is a finding.
Fix
Remove default system accounts (such as bin, sys, adm, or others) from the cron.allow file if it exists, or add those accounts to the cron.deny file.
V-11996
No Change
Findings ID: | GEN003500 | Rule ID: | SV-27402r1_rule | Severity: | low | CCI: | CCI-000366 |
---|
Discussion
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 AdministratorECCD-1, ECCD-2Checks
# lsuser -a core ALLIf any user does not have a value of core = 0, this is a finding.
Fix
# chsec -f /etc/security/limits -s default -a core=0
V-11997
No Change
Findings ID: | GEN003520 | Rule ID: | SV-38861r1_rule | Severity: | low | CCI: | CCI-000225 |
---|
Discussion
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 AdministratorECLP-1Checks
Determine the core file copy location.#sysdumpdev -l | grep -i "core dir"
Check the ownership of the kernel core dump data directory.
# ls -ld < dump file location >
If the kernel core dump data directory is not owned by root, this is a finding.
Fix
Change the owner of the kernel core dump data directory to root.# chown root /var/adm/ras
Supplementary Information: The location of the kernel dump area should be moved out of /var/adm/ras. This directory may be world read/writeable. A suggestion would be to create /var/adm/kcore; chown root:sys /var/adm/kcore; chmod 700 /var/adm/kcore.
Change where the system copies its kernel core files to.
sysdumpdev -d /var/adm/kcore
V-11999
No Change
Findings ID: | GEN003540 | Rule ID: | SV-39504r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
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-1Checks
On 64-bit systems, verify the sed_config (Stack Execution Disable) setting is "all".# lsattr -El sys0 -a sed_config
If the second field is not "all", this is a finding.
(32-bit systems do not support sed_config. This is a permanent finding on 32-bit AIX systems.)
Fix
Change the sed_config setting to disable stack execution for all processes.# chdev -l sys0 -a sed_config=all
To assess the impact of updating sed_config, the "all+monitor" setting may be used temporarily. This temporary update does not mitigate the finding.
Reboot the system for the new setting to take effect.
V-12002
No Change
Findings ID: | GEN003600 | Rule ID: | SV-38948r1_rule | Severity: | medium | CCI: | CCI-001551 |
---|
Discussion
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-1Checks
# /usr/sbin/no -o ipsrcrouteforwardIf the returned value is not 0, this is a finding.
Fix
# /usr/sbin/no -po "ipsrcrouteforward=0"
V-12003
No Change
Findings ID: | GEN003620 | Rule ID: | SV-38870r1_rule | Severity: | low | CCI: | CCI-001208 |
---|
Discussion
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-1Checks
Determine if the /home path is a separate file system.#df -k /home
If /home is not on its own file system, this is a finding.
Fix
Migrate the /home (or equivalent) path onto a separate file system.
V-12004
No Change
Findings ID: | GEN003660 | Rule ID: | SV-12505r2_rule | Severity: | medium | CCI: | CCI-000126 |
---|
Discussion
Monitoring and recording successful and unsuccessful logins assists in tracking unauthorized access to the system.System AdministratorECAR-2, ECAR-3Checks
Check /etc/syslog.conf and verify the auth facility is logging both the notice and info level messages by using one of the procedures below.# grep "auth.notice" /etc/syslog.conf
# grep "auth.info" /etc/syslog.conf
OR
# grep 'auth.*' /etc/syslog.conf
If auth.* is not found, and either auth.notice or auth.info is not found, this is a finding.
Fix
Edit /etc/syslog.conf and add local log destinations for auth.* or both auth.notice and auth.info.
V-12005
No Change
Findings ID: | GEN003700 | Rule ID: | SV-12506r2_rule | Severity: | medium | CCI: | CCI-000305 |
---|
Discussion
Unnecessary services should be disabled to decrease the attack surface of the system.System AdministratorECSC-1Checks
First, determine if inetd/xinetd is running.# ps -ef |grep inetd
If inetd is not running, this is not a finding.
# grep -v "^#" /etc/inetd.conf
If no active services are found, yet the inetd daemon is running, this is a finding.
Fix
Remove or disable the inetd startup scripts and kill the service.
V-12006
No Change
Findings ID: | GEN004540 | Rule ID: | SV-38885r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
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 AdministratorECSC-1Checks
Check to see if help is disabled in Sendmail.Procedure:
# telnet <host> 25
help
If the help command returns any Sendmail version information, this is a finding.
Fix
To disable the SMTP HELP command create an empty Sendmail help file.# > /etc/mail/help
V-12010
Updated
Findings ID: | GEN004800 | Rule ID: | SV-39176r |
Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
FTP is typically unencrypted and, therefore, presents confidentiality and integrity risks.Checks
Determine if unencrypted ftpProcedure:
# grep ftp /etc/inetd.conf
# grep telnet /etc/inetd.conf
If
If it is not, this is a finding.
Fix
Edit /etc/inetd.conf and comment out or remove the ftp# vi /etc/inetd.conf
Restart the inetd service.
# refresh -s inetd
V-12011
No Change
Findings ID: | GEN005040 | Rule ID: | SV-38813r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-2Checks
Check the umask setting for the "ftp" user.Procedure:
# lsuser -a umask ftp
If the umask value does not return 077 or 77, this is a finding.
Check the default umask that the ftpd daemon is running with
# grep ftpd /etc/inetd.conf
If there is not a -u077 argument on the ftpd, this is a finding.
Fix
Add the arguments -u077 to the ftpd on the /etc/inetd.conf and refresh inetd.#vi /etc/inetd.conf
#refresh -s inetd
Change the umask of the ftp user.
#chuser umask=077 ftp
V-12014
No Change
Findings ID: | GEN005180 | Rule ID: | SV-12515r2_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
.Xauthority files ensure the user is authorized to access the 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-1Checks
Check the file permissions for the .Xauthority files in the home directories of users of X.Procedure:
# cd ~<X user>
# ls -lL .Xauthority
If the file mode is more permissive than 0600, this is finding.
Fix
Change the mode of the .Xauthority files.Procedure:
# chmod 0600 .Xauthority
V-12016
No Change
Findings ID: | GEN005220 | Rule ID: | SV-12517r2_rule | Severity: | medium | CCI: | CCI-000297 |
---|
Discussion
If access to the X server is not restricted, a user's X session may be compromised.System AdministratorECCD-1, ECCD-2Checks
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 files, where * is a display number that may be 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
Create an X*.hosts file, where * is a display number that may be used to limit X window connections. Add the list of authorized X clients to the file.
V-12017
No Change
Findings ID: | GEN005240 | Rule ID: | SV-12518r2_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
If unauthorized clients are permitted access to the X server, a user's X session may be compromised.System AdministratorECCD-1, ECCD-2Checks
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
Remove unauthorized clients from the xauth configuration.# xauth remove <display name>
V-12018
No Change
Findings ID: | GEN005260 | Rule ID: | SV-38954r1_rule | Severity: | medium | CCI: | CCI-001436 |
---|
Discussion
If unauthorized clients are permitted access to the X server, the user's X session may be compromised.System AdministratorECSC-1Checks
Determine if the X Window system is running.Procedure:
# ps -ef |grep X
Ask the SA if the X Window system is an operational requirement. If it is not, this is a finding.
Fix
Disable the X Windows server on the system.Comment out /etc/rc.dt out of /etc/inittab
V-12019
No Change
Findings ID: | GEN005360 | Rule ID: | SV-38920r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Determine the owner of the SNMP configuration file. Consult vendor documentation to determine the location and name of the file.Procedure:
# find / -name "snmpd*.conf"
# ls -lL <snmpd.conf>
If the snmpd.conf file is not owned by root, this is a finding.
Fix
Change the owner of the snmpd.conf file to bin.Procedure:
# chown bin <snmpd.conf file>
V-12020
No Change
Findings ID: | GEN005440 | Rule ID: | SV-39205r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
Syslog messages are typically unencrypted and may contain sensitive information and are, therefore, restricted to the enclave.System AdministratorECSC-1Checks
NOTE: This will virtually always require a manual review. Ask the SA if the loghost server is collecting data for hosts outside the local enclave. If it is, this is a finding.Fix
Configure the hosts outside of the local enclave to not log to this system.
V-12021
No Change
Findings ID: | GEN005480 | Rule ID: | SV-38894r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
Unintentionally running a syslog server that accepts 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-1Checks
Verify syslogd is running with the -R option.#ps -ef | grep syslogd | grep -v grep
If the -R option is not present, this is a finding.
Fix
Change the syslogd arguments in the src subsystem control and restart the syslogd daemon.# chssys -s syslogd -a '-R'
# stopsrc -s syslogd
# startsrc -s syslogd
V-12022
No Change
Findings ID: | GEN005540 | Rule ID: | SV-38955r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
The SSH daemon must be configured for IP filtering to provide a layered defense against connection attempts from unauthorized addresses.System AdministratorECSC-1Checks
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 and this is a finding.
Fix
Add appropriate IP restrictions for SSH to the /etc/hosts.deny and/or /etc/hosts.allow files.TCP Wrappers can be installed using SMIT from the AIX expansion pack as fileset netsec.options.tcpwrappers.
V-12023
No Change
Findings ID: | GEN005600 | Rule ID: | SV-38821r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
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-1Checks
#no -o ipforwardingIf the value returned is not 0, this is a finding.
Fix
Disable IPv4 forwarding on the system.#no -p -o ipforwarding=0
V-12024
No Change
Findings ID: | GEN006000 | Rule ID: | SV-41525r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
Public Instant Messaging (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 email 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 used to access internal or DoD-controlled IM services are permitted.System AdministratorECIM-1
Checks
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
Uninstall the IM client from the system, or configure the client to only connect to DoD-approved IM services.
V-12025
No Change
Findings ID: | GEN006040 | Rule ID: | SV-12526r2_rule | Severity: | medium | CCI: | CCI-001436 |
---|
Discussion
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, and
-BitTorrent.System AdministratorDesignated Approving AuthorityECSC-1
Checks
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, and
- BitTorrent.
If any of these applications are installed, this is a finding.
Fix
Uninstall the peer-to-peer file sharing application(s) from the system.
V-12026
No Change
Findings ID: | GEN006420 | Rule ID: | SV-12527r2_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
The use of hard-to-guess NIS domain names provides additional protection from unauthorized access to the NIS directory information.System AdministratorECSC-1Checks
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.
Fix
Change the NIS domain name to a value difficult to guess. Consult vendor documentation for the required procedure.
V-12028
No Change
Findings ID: | GEN006560 | Rule ID: | SV-41530r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
Timely notifications of potential security compromises minimize the potential damage.Minimally, the system must log these events and the SA and the IAO will receive the notifications during the daily system log review. If feasible, active alerting (such as email or paging) should be employed consistent with the site’s established operations management systems and procedures.Information Assurance OfficerSystem AdministratorECAT-1, ECAT-2
Checks
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
Configure the security tools on the system to notify the IAO and SA when any security issues are detected.
V-12030
No Change
Findings ID: | GEN006620 | Rule ID: | SV-41532r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
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-1Checks
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 in 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
Edit the /etc/hosts.allow and /etc/hosts.deny files to configure access restrictions.
V-12035
No Change
Findings ID: | GEN000000-AIX00080 | Rule ID: | SV-12536r2_rule | Severity: | high | CCI: | CCI-000225 |
---|
Discussion
The SYSTEM attribute in /etc/security/user defines the mechanisms used to authenticate specific user accounts. If the value is set to NONE, other attributes will be used to determine the authentication mechanisms, but if these attributes are not present, no authentication will be performed. To ensure authentication is always used for the system's accounts, the SYSTEM attribute must always be set to a valid setting other than NONE.System AdministratorIAIA-1, IAIA-2
Checks
Examine the /etc/security/user file.# grep SYSTEM /etc/security/user
If the line contains SYSTEM=NONE, this is a finding.
Fix
Edit /etc/security/user and change any SYSTEM=NONE settings to a valid authentication setting.
V-12049
No Change
Findings ID: | GEN003865 | Rule ID: | SV-38880r1_rule | Severity: | medium | CCI: | CCI-000305 |
---|
Discussion
Network analysis tools allow for the capture of network traffic visible to the system.System AdministratorDCPA-1Checks
Determine if any network analysis tools are installed.Procedure:
# find / -name ethereal
# find / -name wireshark
# find / -name tshark
# find / -name netcat
# find / -name tcpdump
# find / -name snoop
If any network analysis tools are found, this is a finding.
Additional Information: The binary tcpdump is provided in the bos.net.tcp.server fileset and this fileset cannot be uninstalled.
Fix
Remove the network analysis tool binary from the system.Procedure:
# rm /usr/sbin/tcpdump
V-12765
Updated
Findings ID: | GEN006640 | Rule ID: | SV-40067r |
Severity: | medium | CCI: | CCI-001668 |
---|
Discussion
Virus scanning software can be used to protect a system from penetration by 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.
Checks
Check if uvscan is scheduled to run:
# grep uvscan /var/spool/cron/crontabs/*
Perform the following command to ensure the virus definition signature files are not older than 14 days.
# ls -la clean.dat names.dat scan.dat
If a virus scanner is not being run daily or the virus definitions are older than 14 days
If the operator is unable to provide a documented configuration for an installed anti-virus software system or if not properly used, this is a finding.
Fix
V-22290
No Change
Findings ID: | GEN000241 | Rule ID: | SV-39091r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
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 (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 AdministratorECSC-1
Checks
Check the root crontab for ntpdate jobs running at least daily.# crontab -l | grep ntpdate
Columns 3, 4, and 5 must be an asterisk (*) for the job to be run daily.
If this job exists, this is not a finding.
OR
Verify the auto-startup of xntpd in /etc/rc.tcpip.
# cat /etc/rc.tcpip | grep -v "^#"
Check the system for a running NTP daemon, which is the preferred method.
# ps -ef | grep ntp
If an (x)ntpd process exists, this is not a finding. Otherwise, this is a finding.
Fix
Enable the NTP daemon for continuous synchronization.Edit /etc/rc.tcpip and enable xntpd daemon. Edit /etc/ntp.conf and add the ntp server entry.
# startsrc -s xntpd
OR
Add a daily or more frequent cronjob to perform synchronization using ntpdate.
NOTE: While it is possible to run ntpdate from a cron script, it is important to mention that ntpdate with contrived cron scripts is no substitute for the NTP daemon, which uses sophisticated algorithms to maximize accuracy and reliability while minimizing resource use.
Finally, since ntpdate polling does not discipline the host clock frequency as does xntpd, the accuracy using ntpdate is limited. The process of passively listening for NTP broadcasts (i.e., placing the line broadcastclient yes in the /etc/ntp.conf file) is preferred over any procedural form of direct server polling for a large network with many nodes needing to be time synchronized. This method is preferred because it significantly reduces the network traffic load related to NTP.
V-22291
No Change
Findings ID: | GEN000242 | Rule ID: | SV-39092r1_rule | Severity: | medium | CCI: | CCI-000160 |
---|
Discussion
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 (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
Check the system for a running NTP daemon.# ps -ef | grep ntp
Verify the auto-startup of xntpd in /etc/rc.tcpip.
# cat /etc/rc.tcpip | grep -v "^#"
Verify at least two external NTP servers are listed in the /etc/ntp.conf file.
# cat /etc/ntp.conf | grep -v "^#" | grep -i server | egrep -v "127.127.1.1|127.127.1.0"
If xntpd is not invoked with at least two external NTP servers listed (127.127.1.0 or 127.127.1.1 are local clock references and therefore not allowed), this is a finding.
Fix
If auto-starting xntpd, add (when necessary) the correct number of (at least two) external servers to the /etc/ntp.conf file. If using ntpdate, add additional NTP servers (at least two are required) to the cron job running ntpdate.
V-22292
No Change
Findings ID: | GEN000244 | Rule ID: | SV-28718r1_rule | Severity: | low | CCI: | CCI-000160 |
---|
Discussion
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 (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 AdministratorECSC-1
Checks
Check the root crontab for ntpdate entries.# crontab -l | grep ntpdate
If the ntpdate command is invoked with NTP servers outside of the enclave, this is a finding.
Check the NTP daemon configuration.
# grep '^server' ntp.conf
If an NTP server is listed outside of the enclave, this is a finding.
Fix
If using ntpdate, remove NTP servers external to the enclave from the cron job running ntpdate.If using the NTP daemon, remove the server line from ntp.conf for each NTP server external to the enclave.
V-22294
No Change
Findings ID: | GEN000250 | Rule ID: | SV-40383r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Determine the owner of the ntp.conf file.# ls -l /etc/ntp.conf
If the owner is not root, this is a finding.
Fix
Change the owner of the ntp.conf file.# chown root ntp.conf
V-22295
No Change
Findings ID: | GEN000251 | Rule ID: | SV-39093r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the group ownership of the NTP configuration file.Procedure:
# ls -lL /etc/ntp.conf
If the group owner is not bin, sys, or system, this is a finding.
Fix
Change the group owner of the NTP configuration file.Procedure:
# chgrp system /etc/ntp.conf
V-22296
No Change
Findings ID: | GEN000252 | Rule ID: | SV-40384r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Determine the mode of the ntp.conf file.# ls -l /etc/ntp.conf
If the mode is more permissive than 0640, this is a finding.
Fix
Change the mode of the ntp.conf file to 0640 or less permissive.# chmod 0640 /etc/ntp.conf
V-22297
No Change
Findings ID: | GEN000253 | Rule ID: | SV-38667r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check for an extended ACL on the NTP configuration file.# aclget /etc/ntp.conf
If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the ntp.conf file.#acledit /etc/ntp.conf
V-22298
No Change
Findings ID: | GEN000450 | Rule ID: | SV-38670r2_rule | Severity: | low | CCI: | CCI-000054 |
---|
Discussion
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 Administrator
Checks
#grep maxulogs /etc/security/user | grep -v \*If no values are returned, or any value returned is not between 1 and 10, this is a finding.
Fix
Configure the system to limit the number of simultaneous logins for user accounts with the chsec command.# chsec -f /etc/security/user -s default -a maxulogs=10
# chsec -f /etc/security/user –s [user] -a maxulogs=10
V-22299
No Change
Findings ID: | GEN000452 | Rule ID: | SV-39095r1_rule | Severity: | low | CCI: | CCI-000052 |
---|
Discussion
Providing users with feedback on when account accesses last occurred facilitates user recognition and reporting of unauthorized account use.System AdministratorECSC-1
Checks
Determine if the system displays the date and time of the last successful login upon logging in. This can be accomplished by logging into the system and verifying whether or not the necessary information is displayed. If the system does not provide this information upon login, this is a finding.Verify the SSH daemon is configured to display last login information.
# cat /etc/ssh/sshd_config | grep -i PrintLastLog
If PrintLastLog is disabled, this is a finding.
Fix
Configure the system to display the date and time of the last successful login upon logging in. Consult OS documentation for the configuration procedure.Enable PrintLastLog in the SSH daemon. To enable PrintLastLog in the SSH daemon, remove any comment disabling this option from /etc/ssh/sshd_config. The line should look like: "PrintLastLog yes".
Restart sshd.
# kill -1 <PID of sshd>
V-22301
No Change
Findings ID: | GEN000510 | Rule ID: | SV-25948r1_rule | Severity: | low | CCI: | CCI-000061 |
---|
Discussion
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
Determine if a publicly-viewable pattern is displayed during a session lock. If the session lock pattern is not publicly-viewable, this is a finding.Fix
Configure the system to display a publicly-viewable pattern during a session lock.
V-22302
No Change
Findings ID: | GEN000585 | Rule ID: | SV-38769r1_rule | Severity: | medium | CCI: | CCI-000205 |
---|
Discussion
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 AdministratorIAIA-1, IAIA-2
Checks
Verify no password hashes in /etc/passwd.# cat /etc/passwd | cut -f2,2 -d":"
If there are password hashes present, this is a finding.
Verify no password hashes in the /etc/security/passwd file begin with the characters other than {ssha256} or {ssha512}
#cat /etc/security/passwd | grep password
If there are password hashes that do not begin with {ssha256} or {ssha512}, this is a finding.
Fix
Configure the system to enforce the correctness of the entire password during authentication.Configure the system to use sha password hashing.
#chsec -f /etc/security/login.cfg -s usw -a pwd_algorithm=ssha256
V-22303
No Change
Findings ID: | GEN000590 | Rule ID: | SV-38938r1_rule | Severity: | medium | CCI: | CCI-000803 |
---|
Discussion
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 that are more vulnerable to compromise.System AdministratorDCNR-1, IAIA-1, IAIA-2Checks
Determine if the system creates password hashes using a FIPS 140-2 approved cryptographic hashing algorithm by verifying the value of pwd_algorithm in /etc/security/login.cfg.# grep pwd_algorithm /etc/security/login.cfg
If the system is not configured to generate password hashes using a FIPS 140-2 approved algorithm, such as SHA256 or a successor, this is a finding.
Fix
Configure the system to use a FIPS 140-2 approved cryptographic hash algorithm for creating password hashes.# chsec -f /etc/security/login.cfg -s usw -a pwd_algorithm=ssha256
V-22304
No Change
Findings ID: | GEN000595 | Rule ID: | SV-38672r1_rule | Severity: | medium | CCI: | CCI-000196 |
---|
Discussion
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 that are more vulnerable to compromise.System AdministratorDCNR-1, IAIA-1, IAIA-2Checks
Fix
Change the passwords for all accounts using non-compliant password hashes.# passwd account
OR
# smitty passwd
(This requires that GEN000590 is already met.)
V-22306
No Change
Findings ID: | GEN000750 | Rule ID: | SV-38677r2_rule | Severity: | medium | CCI: | CCI-000195 |
---|
Discussion
To ensure password changes are effective in their goals, the system must ensure 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 AdministratorChecks
Check the value of the mindiff parameter.Procedure:
#lsuser -a mindiff ALL
If any user's mindiff is less than 8, this is a finding.
Fix
Use the chsec command to change mindiff to 8.# chsec -f /etc/security/user -s default -a mindiff=8
# chuser mindiff=8 < user id >
V-22307
No Change
Findings ID: | GEN000790 | Rule ID: | SV-38678r1_rule | Severity: | medium | CCI: | CCI-000189 |
---|
Discussion
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 using repeated logon attempts until the correct account and password pair is guessed. Utilities, such as cracklib, can be used to validate that passwords are not dictionary words and meet other criteria during password changes.System AdministratorIAIA-1, IAIA-2
Checks
Procedure:#lsuser -a dictionlist ALL
If the dictionlist is blank or not listed, the system is not checking against a dictionary of words that are not to be used for passwords. This is a finding.
Fix
Install the default dictionary of words from the 'bos.data' fileset with smitty or installp.# smitty installp
#installp bos.data
Customize or modify the dictionary in /usr/share/dict/words as necessary.
#vi /usr/share/dict/words
Add a dictionary list to /etc/security/user file with the chsec command.
#chsec -f /etc/security/user -s default -a dictionlist=/usr/share/dict/words
V-22308
No Change
Findings ID: | GEN000850 | Rule ID: | SV-38680r1_rule | Severity: | low | CCI: | CCI-000009 |
---|
Discussion
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-1Checks
Examine the sugroups of the root user. Generally only users in the adm group should have su to root capacity.Procedure:
#lsuser -a sugroups root
If this is blank or ALL, this is a finding.
Fix
Use the chsec command to only allow users in the adm group to su to root.#chsec -f /etc/security/user -s root -a sugroups=adm
V-22309
No Change
Findings ID: | GEN000930 | Rule ID: | SV-38690r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
File system extended ACLs provide access to files beyond what is allowed by the mode numbers of the files.System AdministratorECLP-1Checks
Verify the root account's home directory has no extended ACL.Procedure:
# aclget ~root
If extended permissions are enabled, the directory has an extended ACL, and this is a finding.
Fix
Remove the extended ACL from the root account's home directory.#acledit ~root
Change extended attributes to disabled.
V-22310
No Change
Findings ID: | GEN000945 | Rule ID: | SV-38770r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
The library search path environment variable(s) contains 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-1Checks
Verify the LIBPATH and LD_LIBRARY_PATH variables are empty or not defined for the root user.# echo $LD_LIBRARY_PATH
# echo $LIBPATH
If a path list is returned, this is a finding.
Fix
Edit the root user's initialization files and remove any definition of LD_LIBRARY_PATH and LIBPATH.
V-22311
No Change
Findings ID: | GEN000950 | Rule ID: | SV-38772r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
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-1Checks
Verify the LDR_PRELOAD environment variable is empty or not defined for the root user.# env | grep LDR_PRELOAD
If a path is returned, this is a finding.
Fix
Edit the root user's initialization files and remove any definition of LDR_PRELOAD.
V-22312
No Change
Findings ID: | GEN001170 | Rule ID: | SV-40084r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
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 AdministratorECSC-1Checks
Determine if any file on the system does not have a valid group owner.# find / -nogroup -print
If any such files are found, this is a finding.
Fix
Change the group owner for each file without a valid group owner.# chgrp <a-valid-group> /tmp/a-file-without-a-valid-group-owner
V-22313
No Change
Findings ID: | GEN001190 | Rule ID: | SV-38685r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
Restricting permission on daemons will protect them from unauthorized modification and possible system compromise.System AdministratorECLP-1Checks
Verify network services daemon files have no extended ACLs.# aclget <directory>/<network service daemon>
NOTE: Network daemons that may not reside in these directories (such as httpd or sshd) must also be checked for extended ACLs.
If any of the service daemons have extended attributes enabled, this is a finding.
Fix
Remove the extended ACL(s) from the network service daemon file(s).#acledit < directory >/< network service daemon >
Disable extended permissions.
V-22314
No Change
Findings ID: | GEN001210 | Rule ID: | SV-38686r1_rule | Severity: | medium | CCI: | CCI-001499 |
---|
Discussion
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
Verify all system command files have no extended ACLs.# aclget /etc
# aclget /bin
# aclget /usr/bin
# aclget /usr/lbin
# aclget /usr/ucb
# aclget /sbin
# aclget /usr/sbin
If any of the command files have extended permissions enabled, this is a finding.
Fix
Remove the extended ACL(s) from the system command file(s) and set the extended permissions to disabled.#acledit < command path >/< command file>
V-22315
No Change
Findings ID: | GEN001270 | Rule ID: | SV-38687r1_rule | Severity: | medium | CCI: | CCI-001314 |
---|
Discussion
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-1Checks
Determine if any system log 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 that provides access beyond the needs of authorized software, this is a finding.Check to see if extended permissions are disabled.
#aclget <directory>/<file>
Fix
Remove the extended ACL(s) from the system log file(s) and disable extended permissions.# acledit < directory >/< file>
V-22316
No Change
Findings ID: | GEN001290 | Rule ID: | SV-38688r1_rule | Severity: | low | CCI: | CCI-000225 |
---|
Discussion
If manual pages are compromised, misleading information could be inserted, causing actions that may compromise the system.System AdministratorECLP-1Checks
Determine if any manual page files on the system have extended ACLs.Check to see if extended permissions are disabled.
#aclget < directory >/< file >
If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACLs from system manual page file(s) and disable extended permissions.#acledit < directory >/< file >
V-22317
No Change
Findings ID: | GEN001310 | Rule ID: | SV-38689r1_rule | Severity: | medium | CCI: | CCI-001499 |
---|
Discussion
Unauthorized access could destroy the integrity of the library files.System AdministratorECLP-1Checks
Determine if any system library file has an extended ACL. If so, this is a finding.Check to see if extended permissions are disabled. If extended permissions are not disabled, this is a finding.
#aclget < directory >/< file >
Fix
Remove the extended ACL(s) from the system library file(s) and disable extended permissions.#acledit < directory >/< file >
V-22318
No Change
Findings ID: | GEN001361 | Rule ID: | SV-38691r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
NIS/NIS+/yp files are part of the system's identification and authentication processes and are, therefore, critical to system security. ACLs on these files could result in unauthorized modification, which could compromise these processes and the system. System AdministratorECLP-1Checks
Determine if any NIS/NIS+/yp command files have an extended ACL. Check if extended permissions are disabled.Procedure:
# aclget /var/nis
# aclget /var/yp
If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the NS/NIS+/yp command file(s) and disable extended permissions.#acledit < directory >/< file >
V-22319
No Change
Findings ID: | GEN001362 | Rule ID: | SV-26395r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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
Verify the /etc/resolv.conf file is owned by root.Procedure:
# ls -l /etc/resolv.conf
If the file is not owned by root, this is a finding.
Fix
Change the owner of the /etc/resolv.conf file to root.# chown root /etc/resolv.conf
V-22320
No Change
Findings ID: | GEN001363 | Rule ID: | SV-39099r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the group ownership of the resolv.conf file.Procedure:
# ls -lL /etc/resolv.conf
If the file is not group-owned by bin, sys, or system, this is a finding.
Fix
Change the group owner of the /etc/resolv.conf file to bin, sys, or system.Procedure:
# chgrp system /etc/resolv.conf
V-22321
No Change
Findings ID: | GEN001364 | Rule ID: | SV-26397r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the mode of the /etc/resolv.conf file.Procedure:
# ls -l /etc/resolv.conf
If the file mode is more permissive than 0644, this is a finding.
Fix
Change the mode of the /etc/resolv.conf file to 0644 or less permissive.# chmod 0644 /etc/resolv.conf
V-22322
No Change
Findings ID: | GEN001365 | Rule ID: | SV-38692r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Verify /etc/resolv.conf has no extended ACL.Check if extended permissions are disabled.
Procedure:
#aclget /etc/resolv.conf
If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from /etc/resolv.conf file and disable extended permissions.#acledit /etc/resolv.conf
V-22323
No Change
Findings ID: | GEN001366 | Rule ID: | SV-26410r2_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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 AdministratorChecks
Verify the /etc/hosts file is owned by root.Procedure:
# ls -lL /etc/hosts
If the file is not owned by root, this is a finding.
Fix
Change the owner of the /etc/hosts file to root.# chown root /etc/hosts
V-22324
No Change
Findings ID: | GEN001367 | Rule ID: | SV-39100r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the /etc/hosts file's group ownership.Procedure:
# ls -lL /etc/hosts
If the file is not group-owned by bin, sys, or system, this is a finding.
Fix
Change the group owner of the /etc/hosts file to sys, bin, or system.Procedure:
# chgrp system /etc/hosts
V-22325
No Change
Findings ID: | GEN001368 | Rule ID: | SV-26412r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the mode of the /etc/hosts file.Procedure:
# ls -l /etc/hosts
If the file mode is more permissive than 0644, this is a finding.
Fix
Change the mode of the /etc/hosts file to 0644 or less permissive.# chmod 0644 /etc/hosts
V-22326
No Change
Findings ID: | GEN001369 | Rule ID: | SV-38693r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Verify /etc/hosts has no extended ACL.Check to see if extended permissions are disabled.
Procedure:
#aclget /etc/hosts
If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the /etc/hosts file and disable extended permissions.#acledit /etc/hosts
V-22327
No Change
Findings ID: | GEN001371 | Rule ID: | SV-39330r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Verify the /etc/nsswitch.conf file is owned by root.AIX does not use the /etc/nsswitch.conf file. This check is not applicable.
Procedure:
# ls -l /etc/nsswitch.conf
If the file is not owned by root, this is a finding.
Fix
Change the owner of the /etc/nsswitch.conf file to root.# chown root /etc/nsswitch.conf
V-22328
No Change
Findings ID: | GEN001372 | Rule ID: | SV-39101r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the group ownership of the nsswitch.conf file.AIX does not use the /etc/nsswitch.conf file. This check is not applicable.
Procedure:
# ls -lL /etc/nsswitch.conf
If the file is not group-owned by root, bin, sys, or system, this is a finding.
Fix
Change the group owner of the /etc/nsswitch.conf file to root, bin, sys, or system.Procedure:
# chgrp system /etc/nsswitch.conf
V-22329
No Change
Findings ID: | GEN001373 | Rule ID: | SV-39332r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the mode of the /etc/nsswitch.conf file.AIX does not use the /etc/nsswitch.conf file. This check is not applicable.
Procedure:
# ls -l /etc/nsswitch.conf
If the file mode is more permissive than 0644, this is a finding.
Fix
Change the mode of the /etc/nsswitch.conf file to 0644 or less permissive.# chmod 0644 /etc/nsswitch.conf
V-22330
No Change
Findings ID: | GEN001374 | Rule ID: | SV-39334r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Verify /etc/nsswitch.conf has no extended ACL.AIX does not use the /etc/nsswitch.conf file. This check is not applicable.
Procedure:
# aclget /etc/nsswitch.conf
If extended permissions are enabled, this is a finding.
Fix
Remove the extended ACL from the /etc/nsswitch.conf file.# acledit /etc/nsswitch.conf
V-22332
No Change
Findings ID: | GEN001378 | Rule ID: | SV-26425r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Verify the /etc/passwd file is owned by root.Procedure:
# ls -l /etc/passwd
If the file is not owned by root, this is a finding.
Fix
Change the owner of the /etc/passwd file to root.# chown root /etc/passwd
V-22333
No Change
Findings ID: | GEN001379 | Rule ID: | SV-38723r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the group ownership of the password file.Procedure:
# ls -lL /etc/passwd
If the file is not group-owned by security, bin, sys, or system, this is a finding.
Fix
Change the group owner of the /etc/passwd file to security, bin, sys, or system.Procedure:
# chgrp security /etc/passwd
V-22334
No Change
Findings ID: | GEN001390 | Rule ID: | SV-38724r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Verify the /etc/passwd file has no extended ACL.Procedure:
#aclget /etc/passwd
Check to see if extended permissions are disabled. If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the /etc/passwd file and disable extended permissions.#acledit /etc/passwd
V-22335
No Change
Findings ID: | GEN001391 | Rule ID: | SV-26431r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Verify the /etc/group file is owned by root.Procedure:
# ls -l /etc/group
If the file is not owned by root, this is a finding.
Fix
Change the owner of the /etc/group file to root.# chown root /etc/group
V-22336
No Change
Findings ID: | GEN001392 | Rule ID: | SV-38725r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the group ownership of the /etc/group file.Procedure:
# ls -lL /etc/group
If the file is not group-owned by security, bin, sys, or system, this is a finding.
Fix
Change the group owner of the /etc/group file to security, bin, sys, or system.# chgrp security /etc/group
V-22337
No Change
Findings ID: | GEN001393 | Rule ID: | SV-26433r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the mode of the /etc/group file.Procedure:
# ls -l /etc/group
If the file mode is more permissive than 0644, this is a finding.
Fix
Change the mode of the /etc/group file to 0644 or less permissive.# chmod 0644 /etc/group
V-22338
No Change
Findings ID: | GEN001394 | Rule ID: | SV-38726r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Verify the /etc/group file has no extended ACL.Procedure:
#aclget /etc/group
Check if extended permissions are disabled. If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the /etc/group file and disable extended permissions.#acledit /etc/group
V-22339
No Change
Findings ID: | GEN001410 | Rule ID: | SV-38727r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
The /etc/security/passwd 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-1Checks
Check the ownership of the /etc/security/passwd file.Procedure:
# ls -lL
/etc/security/passwd
If the file is not group-owned by security, bin, sys, or system, this is a finding.
Fix
Change the group owner of the /etc/security/passwd file to security, bin, sys, or system.Procedure:
# chgrp security /etc/security/passwd
V-22340
No Change
Findings ID: | GEN001430 | Rule ID: | SV-38729r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
The /etc/security/passwd 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-1Checks
Verify the /etc/security/passwd file has no extended ACL and check if extended permissions are disabled.Procedure:
#aclget /etc/security/passwd
If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the /etc/security/passwd fileand disable extended permissions.
#acledit /etc/security/passwd
V-22348
No Change
Findings ID: | GEN001475 | Rule ID: | SV-26447r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the /etc/group file for password hashes.Procedure:
# cut -d : -f 2 /etc/group | egrep -v '^(x|!)$'
If any password hashes are returned, this is a finding.
If no password hashes are returned, there is no finding.
Fix
Edit /etc/group and change the password field to an exclamation point (!) to lock the group password.
V-22350
No Change
Findings ID: | GEN001490 | Rule ID: | SV-38730r1_rule | Severity: | low | CCI: | CCI-000225 |
---|
Discussion
Excessive permissions on home directories allow unauthorized access to user files.System AdministratorECLP-1Checks
Verify user home directories have no extended ACLs.Procedure:
# cat /etc/passwd | cut -f 6,6 -d ":" | xargs -n1 aclget
Check if extended permissions are disabled.
If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the user home directory and disable extended permissions.#acledit <directory>/<file>
V-22351
No Change
Findings ID: | GEN001550 | Rule ID: | SV-26453r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
If a user's files are group-owned by a group where the user is not a member, unintended users may be able to access them.System AdministratorECLP-1Checks
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 < users home directory > -exec ls -lLd
3. Obtain the list of GIDs associated with the user's account.
# id < user name >
4. Check the GID lists. If there are GIDs in the file list not present in the user list, this is a finding.
Fix
Change the group of a file not group-owned by a group where the home directory's owner is a member.# chgrp [user's primary group] [file with bad group ownership]
V-22352
No Change
Findings ID: | GEN001570 | Rule ID: | SV-38731r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
Excessive permissions allow unauthorized access to user files.System AdministratorECLP-1Checks
Check the contents of user home directories for files with extended ACLs.Procedure:
# cat /etc/passwd | cut -f 6,6 -d ":" | xargs -n1 -IDIR aclget DIR
OR
#aclget <directory>/<file>
Check if extended permissions are disabled.
If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL(s) from the files and directories in user home directories and disable extended permissions.#acledit <directory>/<file>
V-22353
No Change
Findings ID: | GEN001590 | Rule ID: | SV-38733r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Verify run control scripts have no extended ACLs.Check if extended permissions are disabled.
# ls -l /etc/rc*
# aclget /etc/rc*
# aclget /etc/init.d
If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the run control script(s) and disable extended permissions.#acledit <directory>/<file>
V-22354
Updated
Findings ID: | GEN001605 | Rule ID: | SV-38879r |
Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
The library search path environment variable(s) contains 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,Checks
Verify run control scripts' library search paths.Procedure:
# grep -r LIBPATH /etc/rc*
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
Fix
Edit the run control scriptEdit the run control script and remove any empty entry that is defined.
V-22355
Updated
Findings ID: | GEN001610 | Rule ID: | SV-38881r |
Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
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.Checks
Verify run control scripts' library preload list.# grep -r LDR_PRELOAD /etc/rc*
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
Fix
Edit the run control scripts' library preload list and remove relative pathsEdit the run control script and remove any empty entry that is defined.
V-22356
No Change
Findings ID: | GEN001730 | Rule ID: | SV-38734r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check global initialization files for extended ACLs.Procedure:
#aclget /etc/profile /etc/bashrc /etc/csh.login /etc/csh.cshrc /etc/environment /etc/.login /etc/security/environ /etc/security/.profile
Check if extended permissions are disabled. If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the global initialization file(s) and disable extended permissions.#acledit <directory>/<file>
V-22357
No Change
Findings ID: | GEN001810 | Rule ID: | SV-38736r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
If the skeleton files are not protected, unauthorized personnel could change user startup parameters and possibly jeopardize user files.System AdministratorECLP-1Checks
Check skeleton files for extended ACLs.Procedure:
#aclget /etc/security/.profile
#aclget /etc/security/mkuser.sys
Check if extended permissions are disabled. If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the skeleton file(s) and disable extended permissions.#acledit /etc/security/.profile
#acledit /etc/security/mkuser.sys
V-22358
No Change
Findings ID: | GEN001830 | Rule ID: | SV-38738r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
If the skeleton files are not protected, unauthorized personnel could change user start-up parameters and possibly jeopardize user files.System AdministratorECLP-1Checks
Verify the skeleton files are group-owned by security.Procedure:
# ls -alL /etc/security/.profile /etc/security/mkuser.sys
If a skeleton file is not group-owned by security, this is a finding.
Fix
Change the group owner of the skeleton file to security.Procedure:
# chgrp security /etc/security/.profile /etc/security/mkuser.sys
V-22359
Updated
Findings ID: | GEN001845 | Rule ID: | SV-38842r |
Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
The library search path environment variable(s) contain a list of directories for the dynamic linker to search to find libraries.Checks
#egrep '(LD_LIBRARY_PATH|LIBPATH)'
The LIBPATH or LD_LIBRARY_PATH 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.
Edit the run control script and remove any empty entry that is defined.
#vi /etc/profile /etc/bashrc /etc/security/.login /etc/environment /etc/security/environ
Fix
Edit the global initialization files /etc/profile /etc/bashrc /etc/security/.login /etc/environment /etc/security/environ and remove relative entries from the library search path variables.#vi /etc/profile /etc/bashrc /etc/security/.login /etc/environment /etc/security/environ
V-22360
Updated
Findings ID: | GEN001850 | Rule ID: | SV-38843r |
Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
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.Checks
Check the global initialization files' library preload list.# grep LDR_PRELOAD /etc/profile /etc/bashrc /etc/security/.login /etc/environment /etc/security/environ
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
Fix
Edit the global initialization files and removeEdit the run control script and remove any empty entry that is defined.
V-22361
No Change
Findings ID: | GEN001870 | Rule ID: | SV-26481r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check user home directories for local initialization files group-owned by a group other than the user's primary group or root.1. List user accounts and their primary GID.
# cut -d : -f 1,4 /etc/passwd
2. Check local initialization files for each user.
# ls -alL ~USER/.login ~USER/.cshrc ~USER/.logout ~USER/.profile ~USER/.bash_profile ~USER/.bashrc ~USER/.bash_logout ~USER/.env ~USER/.dtprofile ~USER/.dispatch ~USER/.emacs ~USER/.exrc
3. If any file is not group-owned by root or the user's primary GID, this is a finding.
Fix
Change the group owner of the local initialization file to the user's primary group, or root.# chgrp [USER's primary GID] ~USER/[local initialization file]
V-22362
No Change
Findings ID: | GEN001890 | Rule ID: | SV-38739r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check user home directories for local initialization files with extended ACLs.Procedure:
# cat /etc/passwd | cut -f 6,6 -d ":" | xargs -n1 -IDIR ls -le DIR/.login DIR/.cshrc DIR/.logout DIR/.profile DIR/.bash_profile DIR/.bashrc DIR/.bash_logout DIR/.env DIR/.dtprofile DIR/.dispatch DIR/.emacs DIR/.exrc
Procedure:
#aclget <directory>/<file> and check if extended permissions are disabled. If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the local initialization file(s) and disable extended permissions.#acledit <directory>/<file>
V-22363
Updated
Findings ID: | GEN001901 | Rule ID: | SV-38844r |
Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
The library search path environment variable(s) contain a list of directories for the dynamic linker to search to find libraries.Checks
Verify local initialization files have library search path containing only a# cat /etc/passwd | cut -f 1,1 -d ":" | xargs -n1 -IUSER sh -c 'grep -l LIB ~USER/.*'
The LIBPATH and LD_LIBRARY_PATH variables are 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
Fix
Edit the local initialization fileEdit the local initialization file(s) and remove any empty entry that is defined.
V-22364
Updated
Findings ID: | GEN001902 | Rule ID: | SV-39102r |
Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
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.Checks
Verify local initialization files have library preload list containing only aProcedure:
# cat /etc/passwd | cut -f 1,1 -d ":" | xargs -n1 -IUSER sh -c "grep -l LDR_PRELOAD ~USER/.*"
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
Fix
Edit the local initialization file and removeEdit the local initialization file and remove any empty entry that is defined for the LDR_PRELOAD
V-22365
No Change
Findings ID: | GEN002210 | Rule ID: | SV-38848r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the group ownership of each shell referenced.Procedure:
# cat /etc/shells | xargs -n1 ls -l
If any shell is not group owned by root, bin, sys, or system, this is a finding.
#grep shells /etc/security/login.cfg | grep -v \* | cut -f 2 -d = | sed s/,/\ /g | xargs -n1 ls -l
If any shell is not group owned by root, bin, sys, or system, this is a finding.
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
Change the group owner of the shell to root, bin, sys, or system.# chgrp system < shell >
V-22366
No Change
Findings ID: | GEN002230 | Rule ID: | SV-38744r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
Shells with world/group write permissions give the ability to maliciously modify the shell to obtain unauthorized access.System AdministratorECLP-1Checks
Check the permissions of each shell referenced in /etc/shells.Procedure:
# cat /etc/shells
For each shell listed, run aclget <shell path>
#aclget <shell>
Check the permissions of each shell referenced in /etc/security/login.cfg.
Procedure:
#grep shells /etc/security/login.cfg
For each shell listed, run aclget <shell path>
# aclget <shell>
Otherwise, check any shells found on the system.
# find / -name "*sh
#aclget <directory>/<file>
If extended permissions are enabled on any shell, this is a finding.
Fix
Remove the extended ACL from the shell file(s) and disable extended permissions.#acledit <directory>/<file>
V-22367
No Change
Findings ID: | GEN002330 | Rule ID: | SV-38743r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
File system ACLs can provide access to files beyond what is allowed by the mode numbers of the files.System AdministratorECLP-1Checks
Determine the audio device files for the system.Procedure:
# /usr/sbin/lsdev -C | grep -i audio
#aclget /dev/*aud0
Check if extended permissions are disabled. If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the audio device file(s) and disable extended permissions.#acledit <directory>/<file>
V-22368
No Change
Findings ID: | GEN002430 | Rule ID: | SV-38747r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
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-1Checks
If the system does not support a nodev option, this is not applicable.Check /etc/filesystems and verify the nodev mount option (options = ) is used on any file systems mounted from removable media or network shares, or file systems not containing any approved device files. If any such file system is not using the nodev option, this is a finding.
Fix
Edit /etc/filesystems and add the options = nodev to all entries for remote or removable media file systems, and file systems containing no approved device files.
V-22369
No Change
Findings ID: | GEN002710 | Rule ID: | SV-38748r1_rule | Severity: | medium | CCI: | CCI-000163 |
---|
Discussion
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-1Checks
Procedure:# grep -p bin: /etc/security/audit/config
Directories and files to search will be listed under the bin stanza.
#aclget <directory>/<file>
Check if extended permissions are disabled. If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the system audit file(s) and disable extended permissions.#acledit <directory>/<file> and disable extended permissions
V-22370
No Change
Findings ID: | GEN002715 | Rule ID: | SV-38749r1_rule | Severity: | low | CCI: | CCI-001493 |
---|
Discussion
To prevent unauthorized access or manipulation of system audit logs, the tools for manipulating those logs must be protected.System AdministratorECLP-1Checks
Determine if the system audit tool executables are owned by root. Audit tools include, but are not limited to, audit, auditcat, auditconv, auditpr, auditselect, auditstream, auditbin, and auditmerge.Procedure:
ls -lL `which <audit tool executable>`
If any system audit tool executable is not owned by root, this is a finding.
Fix
Change the owner of the system audit tool executables to root.#chown root <system audit tool executable>
V-22371
No Change
Findings ID: | GEN002716 | Rule ID: | SV-38906r1_rule | Severity: | low | CCI: | CCI-001493 |
---|
Discussion
To prevent unauthorized access or manipulation of system audit logs, the tools for manipulating those logs must be protected.System AdministratorECLP-1Checks
Determine the group ownership of system audit tool executables. Audit tools include, but are not limited to, audit, auditcat, auditconv, auditpr, auditselect, auditstream, auditbin, and auditmerge.Procedure:
# ls -lL `which <audit tool executable>`
If any system audit tool executable is not group-owned by bin, sys, or system, this is a finding.
Fix
Change the group owner of system audit tool executables to root, bin, sys, or system.Procedure:
# chgrp system < system audit tool executable>
V-22372
No Change
Findings ID: | GEN002717 | Rule ID: | SV-38778r1_rule | Severity: | low | CCI: | CCI-001493 |
---|
Discussion
To prevent unauthorized access or manipulation of system audit logs, the tools for manipulating those logs must be protected.System AdministratorECLP-1Checks
Determine if system audit tool executables have a mode more permissive than 0750. If any do, this is a finding. Audit tools include, but are not limited to, audit, auditcat, auditconv, auditpr, auditselect, auditstream, auditbin, and auditmerge.Fix
Many audit tools have SUID bit set. Before changing permissions on system audit tool executables, check the file permissions for SUID bits. Change the mode of system audit tool executables to 0750.#chmod 0750 or 4750 <system audit tool executable>
Document all changes made.
V-22373
No Change
Findings ID: | GEN002718 | Rule ID: | SV-38779r1_rule | Severity: | low | CCI: | CCI-001493 |
---|
Discussion
To prevent unauthorized access or manipulation of system audit logs, the tools for manipulating those logs must be protected.System AdministratorECLP-1Checks
Determine if system audit tool executables have extended ACLs Audit tools include, but are not limited to audit, auditcat, auditconv, auditpr, auditselect, auditstream, auditbin, and auditmerge.Procedure:
#aclget <system audit tool executable>
Check if extended permissions are disabled. If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the system audit tool executable(s) and disable extended permissions.#acledit <system audit tool executable>
V-22376
No Change
Findings ID: | GEN002750 | Rule ID: | SV-38851r1_rule | Severity: | low | CCI: | CCI-000018 |
---|
Discussion
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-1Checks
Determine if the audit system is configured to audit account creation.Procedure:
# more /etc/security/audit/events
If auditing of the USER_Create event is not configured, check the USER_Create audit event is defined in the audit classes' stanza of the /etc/security/audit/config file.
Procedure:
#more /etc/security/audit/config
Make note of the audit class the USER_Create event is associated with.
If the USER_Create event is not associated with any audit classes in the classes: stanza, this is a finding.
Verify the audit class is associated with the default user and all other user ids listed in the users: stanza of the /etc/security/audit/config file.
Procedure:
#more /etc/security/audit/config
If the class(es) the USER_Create event is not associated with the default user and all the system users in the 'users:' stanza, this is a finding.
Fix
Configure the audit system to audit account creation.Edit /etc/security/audit/events and add the User_Create event to the list of audited events.
Edit /etc/security/audit/config and add the USER_Create audit event to an audit class in the classes: stanza.
Edit the /etc/security/audit/config and assign the audit classes with the USER_Create event to the all users listed in the users: stanza.
V-22377
No Change
Findings ID: | GEN002751 | Rule ID: | SV-38852r1_rule | Severity: | low | CCI: | CCI-001403 |
---|
Discussion
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-1Checks
Determine if the audit system is configured to audit account modification.Procedure:
# more /etc/security/audit/events
If auditing of the USER_Change event is not configured, this is a finding.
Verify the USER_Change audit event is defined in the audit classes' stanza classes: of the /etc/security/audit/config file.
Procedure:
#more /etc/security/audit/config
Make note of the audit class(es) the USER_Change event is associated with.
If the USER_Change event is not associated with any audit classes in the classes: stanza, this is a finding.
Verify the audit class is associated with the default user and all other user ids listed in the users: stanza of the /etc/security/audit/config file.
Procedure:
#more /etc/security/audit/config
If the class(es) the USER_Change event is not associated with the default user and all the system users in the users: stanza, this is a finding.
Fix
Configure the system to audit account modification.Edit /etc/security/audit/events and add the USER_Change event to the list of audited events.
Edit /etc/security/audit/config and add the USER_Change audit event to an audit class in the classes: stanza.
Edit /etc/security/audit/config and assign the audit classes with the USER_Change event to the all users listed in the users: stanza.
V-22378
No Change
Findings ID: | GEN002752 | Rule ID: | SV-38853r1_rule | Severity: | low | CCI: | CCI-001404 |
---|
Discussion
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-1Checks
Determine if the system is configured to audit account disabling.Procedure:
# more /etc/security/audit/events
If auditing of the USER_Change and USER_Locked events are not configured, this is a finding.
Check the USER_Change and USER_Locked audit event(s) are defined in the audit classes' stanza classes: of the /etc/security/audit/config file.
Procedure:
#more /etc/security/audit/config
Make note of the audit class(es) the USER_Change and USER_Locked events are associated with.
If the USER_Change and USER_Locked events are not associated with any audit classes in the classes: stanza, this is a finding.
Verify the audit class is associated with the default user and all other user ids listed in the users: stanza of the /etc/security/audit/config file.
Procedure:
#more /etc/security/audit/config
If the class(es) the USER_Change and USER_Locked events are not associated with the default user and all the system users in the users: stanza, this is a finding.
Fix
Configure the system to audit account disabling.Edit /etc/security/audit/events and add the USER_Change and USER_Locked events to the list of audited events.
Edit /etc/security/audit/config and add the USER_Change and USER_Locked audits event to an audit class in the classes: stanza.
Edit the /etc/security/audit/config and assign the audit classes with the USER_Change and USER_Locked events to the all users listed in the users: stanza.
V-22382
No Change
Findings ID: | GEN002753 | Rule ID: | SV-38854r1_rule | Severity: | low | CCI: | CCI-001405 |
---|
Discussion
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-1Checks
Determine if the system is configured to audit account termination.Procedure:
# more /etc/security/audit/events
If auditing of the USER_Remove event is not configured, this is a finding.
Verify the USER_Remove audit event is defined in the audit classes' stanza classes: of the /etc/security/audit/config file.
Procedure:
#more /etc/security/audit/config
Make note of the audit class(es) the USER_Remove event is associated with.
If the USER_Remove event is not associated with any audit classes in the classes: stanza, this is a finding.
Verify that the audit class is associated with the default user and all other user ids listed in the 'users:' stanza of the /etc/security/audit/config file.
Procedure:
#more /etc/security/audit/config
If the class(es) that the USER_Remove event is not associated with the default user and all the system users in the users: stanza, this is a finding.
Fix
Configure the system to audit account termination.Edit /etc/security/audit/events and add the USER_Remove event to the list of audited events
Edit /etc/security/audit/config and add the USER_Remove audit event to an audit class in the classes: stanza.
Edit the /etc/security/audit/config and assign the audit classes with the USER_Remove event to the all users listed in the users: stanza.
V-22383
No Change
Findings ID: | GEN002825 | Rule ID: | SV-38858r1_rule | Severity: | medium | CCI: | CCI-000126 |
---|
Discussion
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-1Checks
Determine if the system is configured to audit the loading and unloading of dynamic kernel modules.Check the system's audit configuration.
# more /etc/security/audit/events
Confirm the following events are configured:
DEV_Create, FILE_Mknod, DEV_Configure, DEV_Stop, DEV_Unconfigure, and DEV_Remove.
If any of these events are not configured, this is a finding.
Check the File DEV_Create, FILE_Mknod, DEV_Configure, DEV_Stop, DEV_Unconfigure, and DEV_Remove. Audit events are defined in the audit classes stanza classes: of the /etc/security/audit/config file.
#more /etc/security/audit/config
Make note of the audit class(es) the DEV_Create, FILE_Mknod, DEV_Configure, DEV_Stop, DEV_Unconfigure, and DEV_Remove events are associated with.
If the DEV_Create, FILE_Mknod, DEV_Configure, DEV_Stop, DEV_Unconfigure, and DEV_Remove events are not associated with any audit classes in the classes: stanza, this is a finding.
Verify the audit class is associated with the default user and all other user ids listed in the users: stanza of the /etc/security/audit/config file.
#more /etc/security/audit/config
If the class(es) that the DEV_Create, FILE_Mknod, DEV_Configure, DEV_Stop, DEV_Unconfigure, and DEV_Remove events are not associated with the default user and all the system users in the users: stanza, this is a finding.
Fix
Configure the system to audit the loading and unloading of dynamic kernel modules.Edit /etc/security/audit/events and add the DEV_Create, FILE_Mknod, DEV_Configure, DEV_Stop, DEV_Unconfigure, and DEV_Remove events to the list of audited events.
Edit /etc/security/audit/config and add the DEV_Create, FILE_Mknod, DEV_Configure, DEV_Stop, DEV_Unconfigure, and DEV_Remove audit events to an audit class in the classes: stanza.
Edit the /etc/security/audit/config and assign the audit classes that has the DEV_Create, FILE_Mknod, DEV_Configure, DEV_Stop, DEV_Unconfigure and DEV_Remove events to the all users listed in the 'users:' stanza.
V-22384
No Change
Findings ID: | GEN002990 | Rule ID: | SV-38780r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
A cron.allow file that is readable and/or writable by 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-1Checks
Check the permissions of the cron.allow file.#aclget /var/adm/cron/cron.allow
Verify if extended permissions are disabled. If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the cron.allow file and disable extended permissions.#acledit /var/adm/cron/cron.allow
V-22385
No Change
Findings ID: | GEN003050 | Rule ID: | SV-39866r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
To protect the integrity of scheduled system jobs and prevent malicious modification to these jobs, crontab files must be secured.System AdministratorECLP-1Checks
Check the group ownership of the crontab files.# ls -lL /var/spool/cron/crontabs/
If the group owner is not system, cron, or the crontab owner's primary group, this is a finding.
Fix
Change the group owner of the crontab file to system, cron, or the crontab's primary group.Procedure:
# chgrp cron [crontab file]
V-22386
No Change
Findings ID: | GEN003090 | Rule ID: | SV-38782r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the permissions of the crontab files.Get a listing of crontab files.
# ls /var/spool/cron/crontabs
Check all of the crontabs listed for an extended ACL.
# aclget <directory>/<file>
Check if extended permissions are disabled. If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the crontab file(s) and disable extended permissions.#acledit <directory>/<file>
V-22387
No Change
Findings ID: | GEN003110 | Rule ID: | SV-39103r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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
Check the permissions of the crontab directories.# ls -lL /var/spool/cron/crontabs
# aclget < crontab >
# aclget /var/spool/cron
Check if extended permissions are disabled. If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the crontab file(s) and disable extended permissions.#acledit <directory>/<file>
V-22388
No Change
Findings ID: | GEN003190 | Rule ID: | SV-38783r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
Cron logs contain reports of scheduled system activities and must be protected from unauthorized access or manipulation.System AdministratorECLP-1, ECTP-1Checks
#aclget /var/adm/cron/logVerify if extended permissions are disabled. If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the cronlog file and disable extended permissions.#acledit /var/adm/cron/log
V-22389
No Change
Findings ID: | GEN003210 | Rule ID: | SV-38785r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
If there are excessive file permissions for the cron.deny file, sensitive information could be viewed or edited by unauthorized users.System AdministratorECLP-1Checks
#aclget /var/adm/cron/cron.denyVerify if extended permissions are disabled. If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the cron.deny file and disable extended permissions.#acledit /var/adm/cron/cron.deny
V-22390
No Change
Findings ID: | GEN003245 | Rule ID: | SV-38786r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
#aclget /var/adm/cron/at.allowVerify if extended permissions are disabled. If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the at.allow file and disable extended permissions.#acledit /var/adm/cron/at.allow
V-22391
No Change
Findings ID: | GEN003250 | Rule ID: | SV-39346r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
If the group of the cron.allow is not set to system, 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
Determine the group owner of the cron.allow file.Procedure:
# ls -lL /var/adm/cron/cron.allow
If the group owner is not bin, sys, system, or cron, this is a finding.
Fix
Change the group owner of the cron.allow file to bin, sys, system, or cron.Procedure:
# chgrp cron /var/adm/cron/cron.allow
V-22392
No Change
Findings ID: | GEN003252 | Rule ID: | SV-38787r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Determine the mode of the at.deny file.# ls -lL /var/adm/cron/at.deny
If the mode of the at.deny file is more permissive than 0640, this is a finding.
Fix
Change the mode of the at.deny file to 0640.# chmod 0640 /var/adm/cron/at.deny
V-22393
No Change
Findings ID: | GEN003255 | Rule ID: | SV-38788r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Determine if the at.deny file has an extended ACL.#aclget /var/adm/cron/at.deny
Verify if extended permissions are disabled. If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the at.deny file and disable extended permissions.#acledit /var/adm/cron/at.deny
V-22394
No Change
Findings ID: | GEN003270 | Rule ID: | SV-38789r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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 AdministratorECLP-1Checks
Determine the cron.deny file's group owner.Procedure:
# ls -lL /var/adm/cron/cron.deny
If the file is not group-owned by system, bin, sys, or cron, this is a finding.
Fix
Change the group owner of the cron.deny file to sys, system, bin, or cron.Procedure:
# chgrp cron /var/adm/cron/cron.deny
V-22395
No Change
Findings ID: | GEN003410 | Rule ID: | SV-38790r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the permissions of the file.#aclget /var/spool/cron/atjobs
Verify if extended permissions are disabled. If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the at directory and disable extended permissions.#acledit /var/spool/cron/atjobs
V-22396
No Change
Findings ID: | GEN003430 | Rule ID: | SV-39352r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
If the group of the "at" directory is not system, bin, sys, or cron, unauthorized users could be allowed to view or edit files containing sensitive information within the directory.System AdministratorECLP-1Checks
Check the group ownership of the file.Procedure:
# ls -ld /var/spool/cron/atjobs
If the file is not group-owned by bin, sys, system, or cron, this is a finding.
Fix
Change the group ownership of the file to bin, sys, system, or cron.Procedure:
# chgrp cron /var/spool/cron/atjobs
V-22397
No Change
Findings ID: | GEN003470 | Rule ID: | SV-39354r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
If the group-owner of the at.allow file is not set to system, 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-1Checks
Determine the group owner of the at.allow file.Procedure:
# ls -lL /var/adm/cron/at.allow
If the group-owner is not bin, sys, system, or cron, this is a finding.
Fix
Change the group owner of the at.allow file to sys, system, bin, or cron.Procedure:
# chgrp cron /var/adm/cron/at.allow
V-22398
No Change
Findings ID: | GEN003490 | Rule ID: | SV-39356r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
If the group owner of the at.deny file is not set to system, 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-1Checks
Determine the group owner of the at.deny file.Procedure:
# ls -lL /var/adm/cron/at.deny
If the group owner is not bin, sys, system, or cron, this is a finding.
Fix
Change the group owner of the at.deny file to bin, sys, system, or cron.Procedure:
# chgrp cron /var/adm/cron/at.deny
V-22404
No Change
Findings ID: | GEN003510 | Rule ID: | SV-38860r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
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
Determine if kernel core dumps are enabled on the system.#sysdumpdev -l
Look at both the primary and secondary dump devices. If either the primary or secondary dump device is not /dev/sysdumpnull, this is a finding.
Fix
Disable kernel core dumps on the system by setting primary and secondary dump devices to sysdumpnull.#sysdumpdev -P -p /dev/sysdumpnull
#sysdumpdev -P -s /dev/sysdumpnull
V-22405
No Change
Findings ID: | GEN003521 | Rule ID: | SV-38862r1_rule | Severity: | low | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Determine the core file copy location.#sysdumpdev -l | grep -i "core dir"
Determine the group owner of the kernel core dump data directory.
# ls -lLd < directory >
If the group owner is not bin, sys, or system, this is a finding.
Fix
Change the group owner of the kernel core dump data directory to bin, sys, or system.# chgrp sys < directory >
V-22406
No Change
Findings ID: | GEN003522 | Rule ID: | SV-38863r1_rule | Severity: | low | CCI: | CCI-000225 |
---|
Discussion
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 AdministratorECLP-1Checks
Determine the core file copy location.# sysdumpdev -l | grep "core dir"
Determine the mode of the kernel core dump data directory.
# ls -lLd < directory >
If the mode is more permissive than 0700, this is a finding.
Fix
Change the mode of the kernel core dump data directory to 0700.# chmod 0700 < directory >
V-22407
No Change
Findings ID: | GEN003523 | Rule ID: | SV-38864r1_rule | Severity: | low | CCI: | CCI-000225 |
---|
Discussion
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 AdministratorECLP-1Checks
Determine the core file copy location from the sysdumpdev command.#sysdumpdev -l | grep -I "core dir"
Determine if the kernel core dump data directory has an extended ACL.
#aclget < directory >
Verify if extended permissions are disabled. If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the kernel core dump data directory and disable extended permissions.#acledit < directory >
V-22409
No Change
Findings ID: | GEN003602 | Rule ID: | SV-38866r1_rule | Severity: | low | CCI: | CCI-001551 |
---|
Discussion
The processing of Internet Control Message Protocol (ICMP) timestamp requests increases the attack surface of the system.System AdministratorECSC-1Checks
Determine if the system is configured to respond to ICMP Timestamp requests.#lsfilt
If there is no rule blocking ICMP packet type of 13 and ICMP packet type of 14, this is a finding.
Fix
Use SMIT or genfilt commands to configure the system firewall to block ICMP packet types 13, and 14.
V-22410
No Change
Findings ID: | GEN003603 | Rule ID: | SV-38797r1_rule | Severity: | medium | CCI: | CCI-001551 |
---|
Discussion
Responding to broadcast Internet Control Message Protocol (ICMP) echoes facilitates network mapping and provides a vector for amplification attacks.System AdministratorECSC-1Checks
# /usr/sbin/no -o bcastpingIf the value returned is not 0, this is a finding.
Fix
Configure the system to ignore ICMP ECHO_REQUESTs sent to broadcast addresses.# no -po bcastping=0
V-22411
No Change
Findings ID: | GEN003604 | Rule ID: | SV-38798r1_rule | Severity: | medium | CCI: | CCI-001551 |
---|
Discussion
The processing of Internet Control Message Protocol (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.System AdministratorECSC-1Checks
# /usr/sbin/no -o bcastpingIf the value returned is not 0, this is a finding.
Fix
Configure the system to ignore ICMP Timestamp requests sent to broadcast addresses.#no -po bcastping=0
V-22412
Updated
Findings ID: | GEN003605 | Rule ID: | SV-38799r |
Severity: | medium | CCI: | CCI-001551 |
---|
Discussion
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.System AdministratorChecks
Determine if the system is configured to apply reverse source routing to TCP responses to source-routed packets.# /usr/sbin/no -
If the value is not 0, this is a finding.
Fix
Configure the system to not apply reverse source routing to TCP responses to source-routed packets.# /usr/sbin/no -po nonlocsrcroute=0
V-22413
No Change
Findings ID: | GEN003606 | Rule ID: | SV-38949r1_rule | Severity: | medium | CCI: | CCI-001551 |
---|
Discussion
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.System AdministratorECSC-1Checks
# /usr/sbin/no -o ipsrcroutesendIf the result is not 0, this is a finding.
Fix
# /usr/sbin/no -po "ipsrcroutesend=0"
V-22414
No Change
Findings ID: | GEN003607 | Rule ID: | SV-38800r1_rule | Severity: | medium | CCI: | CCI-001551 |
---|
Discussion
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, such as when IPv4 forwarding is enabled and the system is functioning as a routerSystem AdministratorECSC-1Checks
# /usr/sbin/no -o ipsrcrouterecvIf the result is not 0, this is a finding.
Fix
Configure the system to not accept source-routed IPv4 packets.#/usr/sbin/no -p -o ipsrcrouterecv=0
V-22415
No Change
Findings ID: | GEN003608 | Rule ID: | SV-38867r1_rule | Severity: | medium | CCI: | CCI-001551 |
---|
Discussion
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-1Checks
Determine if the system has proxy ARP enabled.Check Content:
Check the system for non-local published ARP entries.
# arp -a
If any entries are listed as published, this is a finding.
Fix
Remove any non-local published ARP entries.# arp -d < host >
Check system initialization scripts for any commands configuring published ARP entries (such as "arp -s <host> <addr> pub") and remove them.
V-22416
No Change
Findings ID: | GEN003609 | Rule ID: | SV-38801r1_rule | Severity: | medium | CCI: | CCI-001503 |
---|
Discussion
ICMP redirect messages are used by routers to inform hosts 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
# /usr/sbin/no -o ipignoreredirectsIf the value returned is not 1, this is a finding.
Fix
Configure the system to ignore IPv4 ICMP redirect messages.#/usr/sbin/no -p -o ipignoreredirects=1
V-22417
No Change
Findings ID: | GEN003610 | Rule ID: | SV-38802r1_rule | Severity: | medium | CCI: | CCI-001551 |
---|
Discussion
ICMP redirect messages are used by routers to inform hosts 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-1Checks
# /usr/sbin/no -o ipsendredirectsIf the value is not 0, this is a finding.
Fix
#/usr/sbin/no -p -o ipsendredirects=0
V-22418
No Change
Findings ID: | GEN003611 | Rule ID: | SV-38868r1_rule | Severity: | low | CCI: | CCI-000126 |
---|
Discussion
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-1Checks
Determine if the system is configured to log martian packets. Examine the IPF rules on the system.# lsfilt -a
There must be rules to log inbound traffic containing invalid source addresses, which minimally include the system's own addresses and broadcast addresses for attached subnets. If no such rules exist, this is a finding.
Fix
Configure the system to log martian packets.Add rules to log inbound traffic containing invalid source addresses, which minimally include the system's own addresses and broadcast addresses for attached subnets.
For example, consider a system with a single network connection having IP address 192.168.1.10 with a local subnet broadcast address of 192.168.1.255.
Packets with source addresses of 192.168.1.10 and 192.168.1.255 must be logged if received by the system from the network connection.
Use the smit utility or genfilt command to add logging of martian packets (packets with a source address of 192.168.1.10 and 192.168.1.255).
# smitty ipsec4
OR
# genfilt -v4 -a P -s 192.168.1.10 -m 0.0.0.0 -d 0.0.0.0 -M -0.0.0.0 -c all -o any -O any -p 0 -P 0 -w I -l y -i en0
# genfilt -v4 -a P -s 192.168.1.255 -m 0.0.0.0 -d 0.0.0.0 -M -0.0.0.0 -c all -o any -O any -p 0 -P 0 -w I -l y -i en0
V-22419
No Change
Findings ID: | GEN003612 | Rule ID: | SV-38803r1_rule | Severity: | medium | CCI: | CCI-001092 |
---|
Discussion
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 not track a connection until 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-1Checks
# /usr/sbin/no -o clean_partial_connsIf the value returned is not 1, this is a finding.
Fix
#/usr/sbin/no -p -o clean_partial_conns=1
V-22422
Updated
Findings ID: | GEN003650 | Rule ID: | SV-39105r |
Severity: | low | CCI: | CCI-000553 |
---|
Discussion
File system journaling, or logging, can allow reconstruction of file system data after a system crash, thus 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 which also satisfy this requirement.System AdministratorChecks
Determine if the local file systems employ journaling or another mechanism ensuring file system consistency.Procedure:
List all local file system mount points.
#
#lsfs < each file system returned>
If any file systems are not jfs or jfs2, this is a finding.
Fix
Convert local file systems to use journaling or another mechanism ensuring file system consistency.
V-22423
No Change
Findings ID: | GEN003730 | Rule ID: | SV-40385r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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 which could weaken the system's security posture.System AdministratorECLP-1Checks
Check the group ownership of the inetd and xinetd configuration files, and xinetd directory.Procedure:
# ls -alL /etc/inetd.conf /etc/xinetd.conf /etc/xinetd.d
If a file or directory is not group-owned by bin, sys, or system, this is a finding.
Fix
Change the group ownership of the inetd configuration file.Procedure:
# chgrp system /etc/inetd.conf
V-22424
No Change
Findings ID: | GEN003745 | Rule ID: | SV-38805r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the permissions of the inetd configuration file.#aclget /etc/inetd.conf
Check if extended permissions are disabled. If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the /etc/inetd.conf file and disable extended permissions.#acledit /etc/inetd.conf
V-22427
No Change
Findings ID: | GEN003770 | Rule ID: | SV-39112r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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 which could weaken the system's security posture.System AdministratorECLP-1Checks
Check the group ownership of the services file.Procedure:
# ls -lL /etc/services
If the file is not group-owned by bin, sys, or system, this is a finding.
Fix
Change the group owner of the services file.Procedure:
# chgrp system /etc/services
V-22428
No Change
Findings ID: | GEN003790 | Rule ID: | SV-38950r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the permissions of the /etc/services file.#aclget /etc/services
Check if extended permissions are disabled. If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the services file and disable extended permissions.#acledit /etc/services
V-22429
No Change
Findings ID: | GEN003810 | Rule ID: | SV-38874r1_rule | Severity: | medium | CCI: | CCI-001436 |
---|
Discussion
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-1Checks
If the portmap service is required for system operations, this is not a finding.Determine if the portmap service is running.
#ps -ef|grep portmap
If portmap is running, this is a finding.
Fix
Disable the portmap service from auto starting by commenting out portmap from /etc/rc.tcpip.# vi /etc/rc.tcpip
Shutdown the portmap service.
# ps -ef | grep portmap
# kill <pid of portmap>
V-22430
No Change
Findings ID: | GEN003815 | Rule ID: | SV-38952r1_rule | Severity: | medium | CCI: | CCI-000305 |
---|
Discussion
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-1Checks
If the system needs the portmap service to operate, this is not applicable. Consult vendor documentation to determine the name and location of the portmap service.The portmap executable is part of fileset bos.net.tcp.client and is not removable, so this will always be a finding.
Fix
If the portmap or rpcbind service is part of a removable package, consult vendor documentation for the procedure to remove the package. If the service cannot be removed, prevent service activation by removing all permissions from the executable.Procedure:
# chmod 0000 /usr/sbin/portmap
V-22432
No Change
Findings ID: | GEN003830 | Rule ID: | SV-38876r1_rule | Severity: | medium | CCI: | CCI-000068 |
---|
Discussion
The rlogind process provides a typically unencrypted, host-authenticated remote access service. SSH should be used in place of this service.System AdministratorDCPP-1Checks
Determine if the rlogind service is running. If it is, this is a finding.# grep -v "^#" /etc/inetd.conf |grep rlogin
If any results are returned, this is a finding
Fix
Disable the rlogind service out of the '/etc/inetd.conf' file.# vi /etc/inetd.conf
Comment out the rlogind service. Restart the inetd service.
# refresh -s inetd
V-22435
No Change
Findings ID: | GEN003930 | Rule ID: | SV-39875r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
Failure to give group ownership of the hosts.lpd file to 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 AdministratorECLP-1Checks
Check the group ownership of the /etc/hosts.lpd file.Procedure:
# ls -lL /etc/hosts.lpd
If the file is not group owned by bin, sys, or system, this is a finding.
Fix
Change the group owner of the hosts.lpd file.Procedure:
# chgrp sys /etc/hosts.lpd
V-22436
No Change
Findings ID: | GEN003950 | Rule ID: | SV-38807r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the permissions of the /etc/hosts.lpd file.#aclget /etc/hosts.lpd
Check if extended permissions are disabled. If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the hosts.lpd file and disable extended permissions.#acledit /etc/hosts.lpd
V-22437
No Change
Findings ID: | GEN004010 | Rule ID: | SV-38808r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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 possibly leading to system and network compromise.System AdministratorECLP-1Checks
Check the permissions of the /usr/sbin/traceroute file.#aclget /usr/sbin/traceroute
Check if extended permissions are disabled. If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the traceroute file and disable extended permissions.#acledit /usr/sbin/traceroute
V-22438
No Change
Findings ID: | GEN004370 | Rule ID: | SV-40683r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
If the alias file is not group-owned by a system group, an unauthorized user may modify the file to add aliases to run malicious code or redirect e-mail.System AdministratorECLP-1Checks
Check the group ownership of the /etc/mail/aliases file.Procedure:
# ls -lL /etc/mail/aliases
If the file is not group-owned by sys, bin, or system, this is a finding.
Fix
Change the group owner of the /etc/mail/aliases file.Procedure:
# chgrp system /etc/mail/aliases
V-22439
No Change
Findings ID: | GEN004390 | Rule ID: | SV-38809r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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 AdministratorECLP-1Checks
Check the permissions of the /etc/mail/aliases file.#aclget /etc/mail/aliases
Check if extended permissions are disabled. If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the alias file and disable extended permissions.#acledit /etc/mail/aliases
V-22440
No Change
Findings ID: | GEN004410 | Rule ID: | SV-38373r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Examine the contents of the /etc/mail/aliases file.# cat /etc/mail/aliases | cut -f 2,2 -d ":" | grep "|"
For each file referenced, check the group ownership of the file.
# ls -lL <file referenced from aliases>
If the group owner of any file is not root, bin, sys or other, this is a finding.
Fix
Change the group ownership of the file referenced from /etc/mail/aliases.# chgrp root <file referenced from aliases>
V-22441
No Change
Findings ID: | GEN004430 | Rule ID: | SV-38810r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
Excessive permissions on files executed through a mail alias file could result in modification by an unauthorized user, execution of malicious code, and/or system compromise.System AdministratorECLP-1Checks
Examine the contents of the /etc/mail/aliases file.For each file referenced, check the permissions of the file.
#aclget [File referenced from alias]
Check if extended permissions are disabled. If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the file(s) referenced from the aliases file and disable extended permissions.#acledit [File referenced from aliases]
V-22442
No Change
Findings ID: | GEN004510 | Rule ID: | SV-38811r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
If the SMTP service log file has an extended ACL, unauthorized users may be allowed to access or to modify the log file.System AdministratorECLP-1Checks
Examine /etc/syslog.conf and determine the log file(s) receiving logs for mail.crit, mail.debug, mail.*, or *.crit.Check the permissions on these log files.
#aclget [log file]
Check if extended permissions are disabled. If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the SMTP service log file and disable extended permissions.#acledit [ log file ]
V-22444
No Change
Findings ID: | GEN004930 | Rule ID: | SV-39180r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
If the ftpusers file is not group-owned by a system group, an unauthorized user may modify the file to allow unauthorized accounts to use FTP.System AdministratorECLP-1Checks
Check the group ownership of the ftpusers file.Procedure:
# ls -lL /etc/ftpusers
If the file is not group-owned by bin, sys, or system, this is a finding.
Fix
Change the group owner of the ftpusers file.Procedure:
# chgrp system /etc/ftpusers
V-22445
No Change
Findings ID: | GEN004950 | Rule ID: | SV-38812r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the permissions of the /etc/ftpusers file.#aclget /etc/ftpusers
Check if extended permissions are disabled. If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the ftpusers file and disable extended permissions.#acledit /etc/ftpusers
V-22446
No Change
Findings ID: | GEN005190 | Rule ID: | SV-38814r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
.Xauthority files ensure the user is authorized to access that 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-1Checks
Get a list of (non-system account) users and the associated home directories.# cat /etc/passwd | cut -f 1,6 -d ":"
Check the file permissions for the user .Xauthority files.
#aclget .Xauthority
Check if extended permissions are disabled. If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the .Xauthority file(s) and disable extended permissions.#acledit .Xauthority
V-22447
No Change
Findings ID: | GEN005305 | Rule ID: | SV-38816r1_rule | Severity: | medium | CCI: | CCI-001435 |
---|
Discussion
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-1Checks
Determine if the system's SNMP service only uses SNMPv3 or its successors. Consult vendor documentation to determine if earlier versions of SNMP are supported and what configuration is necessary to enable or disable the protocols. Snmpd version 1 was the only version available in AIX versions prior to AIX 5.2.#which snmpd
#ls -l <path to snmpd>
If the results are not /usr/sbin/snmpdv3e or /usr/sbin/snpdv3ne this is an earlier version of the protocol used by the service, this is a finding.
Fix
Configure the system's SNMP service to only use SNMPv3 with encryption or its successors. The SNMP version supporting encryption is an installable fileset on the expansion cd as fileset 'snmp.crypto'.Enable snmpv3 with encryption.
# snmpv3_ssw -e
V-22448
No Change
Findings ID: | GEN005306 | Rule ID: | SV-38890r1_rule | Severity: | medium | CCI: | CCI-001453 |
---|
Discussion
The SNMP service must use SHA-1 or a FIPS 140-2 approved successor for authentication and integrity.System AdministratorDCNR-1Checks
Check all SNMPv3 users for configured authentication protocols.# grep USM_USER /etc/snmpdv3.conf
The 4th field contains the hash used in the authentication protocol. If an entry exists that does not use HMAC-SHA for the authentication protocol, this is a finding.
Fix
Edit the /etc/snmpdv3.conf file. Change any instances of the HMAC-MD5 authentication protocol in USM_USER entries to HMAC-SHA. For all changed USM_USER entries, regenerate authentication keys using the "pwtokey" command and replace the keys in the /etc/snmpdv3.conf file.
V-22450
No Change
Findings ID: | GEN005350 | Rule ID: | SV-38818r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the file permissions for the MIB files.# find / -name *.mib -print
# aclget [mib file]
If the extended attributes are not disabled, this is a finding.
Fix
Remove the extended ACL from the MIB file(s) and change extended attributes to disabled.#acledit [mib file]
V-22451
No Change
Findings ID: | GEN005365 | Rule ID: | SV-38921r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Determine the group owner of the SNMP configuration files.Procedure:
# ls -lL /etc/snmpd.conf /etc/snmpdv3.conf
If the file is not group owned by bin, sys, or system, this is a finding.
Fix
Change the group owner of the SNMP configuration files.Procedure:
# chgrp system /etc/snmpd.conf
# chgrp system /etc/snmpdv3.conf
V-22452
No Change
Findings ID: | GEN005375 | Rule ID: | SV-38819r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
The snmpd.conf file contains authenticators and must be protected from unauthorized access and modification.System AdministratorECLP-1Checks
Determine if the snmpd.conf file or equivalent has an extended ACL.Procedure:
# find / -name "snmpd*.conf"
# aclget < snmpd conf >
If the extended attributes are not disabled, this is a finding.
Fix
Remove the extended ACL from the snmpd.conf file (or equivalent) and change extended attributes to disabled.#acledit < snmpd conf >
V-22453
No Change
Findings ID: | GEN005390 | Rule ID: | SV-26740r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
Unauthorized users must not be allowed to access or modify the /etc/syslog.conf file.System AdministratorECLP-1Checks
Check the permissions of the syslog configuration file.# ls -lL /etc/syslog.conf
If the mode of the file is more permissive than 0640, this is a finding.
Fix
Change the permissions of the syslog configuration file.# chmod 0640 /etc/syslog.conf
V-22454
No Change
Findings ID: | GEN005395 | Rule ID: | SV-38820r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
Unauthorized users must not be allowed to access or modify the /etc/syslog.conf file.System AdministratorECLP-1Checks
Check the permissions of the syslog configuration file.# aclget /etc/syslog.conf
If the extended attributes are not disabled, this is a finding
Fix
Remove the extended ACL from the syslog.conf file and change extended attributes to disabled.#acledit /etc/syslog.conf
V-22455
No Change
Findings ID: | GEN005450 | Rule ID: | SV-26745r1_rule | Severity: | medium | CCI: | CCI-000136 |
---|
Discussion
A syslog server (log host) 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 AdministratorECAT-1Checks
Check the syslog configuration file for remote syslog servers.# grep '@' /etc/syslog.conf | grep -v '^#'
If no line is returned, this is a finding.
Fix
Edit the syslog configuration file and add an appropriate remote syslog server.
V-22456
No Change
Findings ID: | GEN005501 | Rule ID: | SV-39209r1_rule | Severity: | medium | CCI: | CCI-001436 |
---|
Discussion
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-1Checks
Check the SSH client configuration for allowed protocol versions.# grep -i protocol /etc/ssh/ssh_config | grep -v '^#'
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 client is F-Secure, the variable name for SSH 1 compatibility is Ssh1Compatibility, not protocol. If the variable Ssh1Compatiblity is set to yes, this is a finding.
Fix
Edit the /etc/ssh/ssh_config file and add or edit a Protocol configuration line that does not allow versions less than 2.
V-22457
No Change
Findings ID: | GEN005504 | Rule ID: | SV-26750r1_rule | Severity: | medium | CCI: | CCI-000069 |
---|
Discussion
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 AdministratorECSC-1Checks
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
Edit the SSH daemon configuration to specify listening network addresses designated for management traffic.
V-22458
No Change
Findings ID: | GEN005505 | Rule ID: | SV-26751r1_rule | Severity: | medium | CCI: | CCI-000068 |
---|
Discussion
DoD information systems are required to use FIPS 140-2 approved ciphers. SSHv2 ciphers meeting this requirement are 3DES and AES.System AdministratorDCNR-1Checks
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
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.
V-22459
No Change
Findings ID: | GEN005506 | Rule ID: | SV-26752r2_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
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
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
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.
V-22460
No Change
Findings ID: | GEN005507 | Rule ID: | SV-26753r2_rule | Severity: | medium | CCI: | CCI-001453 |
---|
Discussion
DoD information systems are required to use FIPS 140-2 approved cryptographic hash functions.System AdministratorChecks
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
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.
V-22461
No Change
Findings ID: | GEN005510 | Rule ID: | SV-26754r1_rule | Severity: | medium | CCI: | CCI-000068 |
---|
Discussion
DoD information systems are required to use FIPS 140-2 approved ciphers. SSHv2 ciphers meeting this requirement are 3DES and AES.System AdministratorDCNR-1Checks
Check the SSH client configuration for allowed ciphers.# grep -i ciphers /etc/ssh/ssh_config | grep -v '^#'
If no lines are returned, the returned ciphers list contains any cipher not starting with 3des or aes, this is a finding.
Fix
Edit /etc/ssh/ssh_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 ssh_config manpage.
V-22462
No Change
Findings ID: | GEN005511 | Rule ID: | SV-26755r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
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 AdministratorECSC-1
Checks
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
Edit /etc/ssh/ssh_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 ssh_config manpage.
V-22463
No Change
Findings ID: | GEN005512 | Rule ID: | SV-26756r2_rule | Severity: | medium | CCI: | CCI-001453 |
---|
Discussion
DoD information systems are required to use FIPS 140-2 approved cryptographic hash functions.System AdministratorChecks
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
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.
V-22470
No Change
Findings ID: | GEN005521 | Rule ID: | SV-26763r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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 AdministratorECLP-1Checks
Check the SSH daemon configuration for the AllowGroups setting.# grep -i AllowGroups /etc/ssh/sshd_config | grep -v '^#'
If no lines are returned, this is a finding.
Fix
Edit the SSH daemon configuration and add an AllowGroups directive.
V-22471
No Change
Findings ID: | GEN005522 | Rule ID: | SV-26764r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
If a public host key file is modified by an unauthorized user, the SSH service may be compromised.System AdministratorECLP-1Checks
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
Change the permissions for the SSH public host key files.# chmod 0644 /etc/ssh/*key.pub
V-22472
No Change
Findings ID: | GEN005523 | Rule ID: | SV-26765r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
If an unauthorized user obtains the private SSH host key file, the host could be impersonated.System AdministratorECLP-1Checks
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
Change the permissions for the SSH private host key files.# chmod 0600 /etc/ssh/*key
V-22473
No Change
Findings ID: | GEN005524 | Rule ID: | SV-40714r1_rule | Severity: | low | CCI: | CCI-000366 |
---|
Discussion
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 AdministratorECSC-1Checks
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 GSSAPI authentication setting.
# grep -i GSSAPIAuthentication /etc/ssh/sshd_config | grep -v '^#'
If the setting is present and set to "yes", this is a finding. If the setting is absent or set to "no", this is not a finding.
Fix
Edit /etc/ssh/sshd_config and remove the GSSAPIAuthentication setting or change the value to "no".
V-22474
No Change
Findings ID: | GEN005525 | Rule ID: | SV-40715r1_rule | Severity: | low | CCI: | CCI-000366 |
---|
Discussion
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 AdministratorECSC-1Checks
Check the SSH clients configuration for the GSSAPI authentication setting.# grep -i GSSAPIAuthentication /etc/ssh/ssh_config | grep -v '^#'
If the setting is present and set to "yes", this is a finding. If the setting is absent or set to "no", this is not a finding.
Fix
Edit the /etc/ssh/ssh_config file and remove the GSSAPIAuthentication setting or change the GSSAPIAuthentication setting to "no".
V-22475
No Change
Findings ID: | GEN005526 | Rule ID: | SV-40716r1_rule | Severity: | low | CCI: | CCI-000366 |
---|
Discussion
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 AdministratorECSC-1
Checks
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 Kerberos authentication setting.
# grep -i KerberosAuthentication /etc/ssh/sshd_config | grep -v '^#'
If the setting is present and set to "yes", this is a finding. If the setting is missing or set to "no", this is not a finding.
Fix
Edit the /etc/ssh/sshd_config file and remove the KerberosAuthentication setting or change the value of the setting to "no".
V-22482
No Change
Findings ID: | GEN005533 | Rule ID: | SV-26776r1_rule | Severity: | low | CCI: | CCI-000054 |
---|
Discussion
The SSH protocol has the ability to provide multiple sessions over a single connection without reauthentication. A compromised client could use this feature to establish additional sessions to a system without consent or knowledge of the user.Alternate per-connection session limits may be documented if needed for a valid mission requirement. Greater limits are expected to be necessary in situations where TCP or X11 forwarding are used.trueSystem AdministratorECSC-1
Checks
Check the SSH daemon configuration for the MaxSessions setting.# grep -i MaxSessions /etc/ssh/sshd_config | grep -v '^#'
If the setting is not present, or not set to 1, this is a finding.
Fix
Edit the SSH daemon configuration and add or edit the MaxSessions setting value to 1.
V-22485
No Change
Findings ID: | GEN005536 | Rule ID: | SV-40720r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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 AdministratorECLP-1Checks
Check the SSH daemon configuration for the StrictModes setting.# grep -i StrictModes /etc/ssh/sshd_config | grep -v '^#'
If the setting is present and set to "no", this is a finding. If the setting is not present or is set to "yes", this is not a finding.
Fix
Edit the /etc/sshd/sshd_config file and remove the StrictModes setting or change the value of the StrictModes setting to "yes".
V-22486
No Change
Findings ID: | GEN005537 | Rule ID: | SV-40721r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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 AdministratorECLP-1Checks
Check the SSH daemon configuration for the UsePrivilegeSeparation setting.# grep -i UsePrivilegeSeparation /etc/ssh/sshd_config | grep -v '^#'
If the setting is present and set to "no", this is a finding. If the setting is not present or is set to "yes", this is not a finding.
Fix
Edit the /etc/ssh/sshd_config file and remove the UsePrivilegeSeparation setting or change the value of the UsePrivilegeSeparation setting to "yes".
V-22487
No Change
Findings ID: | GEN005538 | Rule ID: | SV-40722r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
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 AdministratorECSC-1Checks
Check the SSH daemon configuration for the RhostsRSAAuthentication setting.# grep -i RhostsRSAAuthentication /etc/ssh/sshd_config | grep -v '^#'
If the setting is present and set to "yes", this is a finding. If the setting is absent or set to "no", this is not a finding.
Fix
Edit the /etc/ssh/sshd_config file and remove the RhostsRSAAuthentication setting or change the value of the RhostsRSAAuthentication setting to "no".
V-22488
No Change
Findings ID: | GEN005539 | Rule ID: | SV-40723r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
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 AdministratorECSC-1Checks
Check the SSH daemon configuration for the Compression setting.# grep -i Compression /etc/ssh/sshd_config | grep -v '^#'
If the setting is present and set to "yes", this is a finding. If the setting is absent or set to "no" or "delayed", this is not a finding.
Fix
Edit the /etc/ssh/sshd_config file and remove the Compression setting or set the Compression setting to "delayed" or "no".
V-22489
No Change
Findings ID: | GEN005550 | Rule ID: | SV-26802r1_rule | Severity: | medium | CCI: | CCI-000048 |
---|
Discussion
Failure to display the DoD logon banner prior to a log in 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 AdministratorECWM-1
Checks
Verify the SSH daemon is configured for logon warning banners.# grep -i banner /etc/ssh/sshd_config | grep -v '^#'
# cat [banner file]
Verify the banner configuration line is present and the file it references contains a logon warning banner.
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."
If the SSH daemon is not configured to display the logon warning banner, this is a finding.
Fix
Edit the SSH daemon configuration and add (or edit) a banner setting referencing a file containing a logon warning 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."
V-22490
No Change
Findings ID: | GEN005570 | Rule ID: | SV-39215r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
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-1Checks
If the system is a router, this is not applicable.If the system does not use IPv6, this is not applicable. Determine if the system has a default route configured for IPv6.
# netstat -r | grep default
If a default route is not defined, this is a finding.
Fix
Configure an IPv6 default route on the system.# smitty route
V-22491
No Change
Findings ID: | GEN005610 | Rule ID: | SV-38822r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
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-1Checks
# /usr/sbin/no -o ip6forwardingIf the value returned is 1, this is a finding.
Fix
Disable IPv6 forwarding on the system.# /usr/sbin/no -p -o ip6forwarding=0
V-22492
No Change
Findings ID: | GEN005750 | Rule ID: | SV-40861r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
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
Change the group ownership of the NFS export configuration file to root, bin, sys, or system.Procedure:
# chgrp root /etc/exports
V-22493
No Change
Findings ID: | GEN005770 | Rule ID: | SV-38823r1_rule | Severity: | low | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
# aclget /etc/exports
If the extended attributes are not disabled, this is a finding.
Fix
Remove the extended ACL from the NFS export configuration file and change extended attributes to disabled.#acledit /etc/exports
V-22496
No Change
Findings ID: | GEN005810 | Rule ID: | SV-26171r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Determine if the NFS exported directories on the system are group-owned by root. If any are not, this is a finding.Fix
Change the group owner of NFS exported directories to root.
V-22497
No Change
Findings ID: | GEN006150 | Rule ID: | SV-38824r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
Excessive permissions could endanger the security of the Samba configuration file and, ultimately, the system and network.System AdministratorECLP-1Checks
Check the group ownership of the Samba configuration file.# aclget /usr/lib/smb.conf
If the extended attributes are not disabled, this is a finding.
Fix
Remove the extended ACL from the /usr/lib/smb.conf file and change extended attributes to disabled.#acledit /usr/lib/smb.conf
V-22498
No Change
Findings ID: | GEN006210 | Rule ID: | SV-38928r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
If the permissions of the smbpasswd file are too permissive, the smbpasswd file may be maliciously accessed or modified, potentially resulting in the compromise of Samba accounts.System AdministratorECLP-1Checks
Check the group ownership of the Samba configuration file.# aclget /var/private/smbpasswd
If the extended attributes are not disabled, this is a finding.
Fix
Remove the extended ACL from the /var/private/smbpasswd file.# acledit /var/private/smbpasswd
V-22499
No Change
Findings ID: | GEN006225 | Rule ID: | SV-39239r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
Samba share authentication does not provide for individual user identification and must not be used.System AdministratorECSC-1Checks
Check the security mode of the Samba configuration.# grep -i security /usr/lib/smb.conf
If the security mode is share, this is a finding.
Fix
Edit the /usr/lib/smb.conf file and change the security setting to user or another valid setting other than share.# vi /usr/lib/smb.conf
V-22500
No Change
Findings ID: | GEN006230 | Rule ID: | SV-39241r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
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 AdministratorIAIA-1, IAIA-2Checks
Check the encryption setting the Samba configuration.# grep -i 'encrypt passwords' /usr/lib/smb.conf
If the setting is not present, or not set to yes, this is a finding.
Fix
Edit the smb.conf file and change the encrypt passwords setting to yes.# vi /usr/lib/smb.conf
V-22501
No Change
Findings ID: | GEN006235 | Rule ID: | SV-39245r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
Guest access to shares permits anonymous access and is not permitted.System AdministratorECSC-1Checks
Check the encryption setting the Samba configuration.# grep -i 'guest ok' /usr/lib/smb.conf
If the setting exists and is set to yes, this is a finding.
Fix
Edit the smb.conf file and change the guest ok setting to no.# vi /usr/lib/smb.conf
V-22502
No Change
Findings ID: | GEN006270 | Rule ID: | SV-38898r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
File system extended ACLs provide access to files beyond what is allowed by the numbers of the files. Excessive permissions on the hosts.nntp file may allow unauthorized modification which could lead to Denial of Service to authorized users or provide access to unauthorized users.System AdministratorECLP-1Checks
Check the permissions of the hosts.nntp file.# find / -type f -name hosts.nntp
# aclget < hosts.nntp file >
If extended permissions are enabled, the file has an extended ACL, this is a finding.
Fix
Remove the extended ACL from the hosts.nntp file.#acledit < hosts.nntp file >
V-22503
No Change
Findings ID: | GEN006290 | Rule ID: | SV-38899r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the permissions of the file.# find / -name hosts.nntp.nolimit
# aclget < hosts.nntp.nolimit >
If the extended permissions are enabled the file has an extended ACL, this is a finding.
Fix
Remove the extended ACL from the hosts.nntp.nolimit file.# acledit < hosts.nntp.nolimit >
Set the extended permissions to disabled.
V-22504
No Change
Findings ID: | GEN006310 | Rule ID: | SV-39258r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the permissions of the file.# find / -name nnrp.access
# ls -lL < nnrp.access >
If extended permissions are enabled, this is a finding.
Fix
Remove the extended ACL from the nnrp.access file.# acledit < nnrp.access >
V-22505
No Change
Findings ID: | GEN006330 | Rule ID: | SV-39262r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the permissions of the file.# find / -name passwd.nntp
# ls -lL < passwd.nntp >
If extended permissions are enabled, this is a finding.
Fix
Remove the extended ACL from the passwd.nntp file.# acledit < passwd.nntp >
V-22506
No Change
Findings ID: | GEN006565 | Rule ID: | SV-38958r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
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 that do not use package management tools.System AdministratorECAT-1
Checks
Check the root crontab for a job invoking the system package management tool to verify the integrity of installed packages.# crontab -l | grep lppchk
If no such job exists, this is a finding.
Fix
Add a job to the root crontab invoking the system package management tool to verify the integrity of installed packages.# lppchk -c
V-22507
No Change
Findings ID: | GEN006570 | Rule ID: | SV-26858r1_rule | Severity: | low | CCI: | CCI-001297 |
---|
Discussion
ACLs can provide permissions beyond those permitted through the file mode and must be verified by file integrity tools.System AdministratorECAT-1Checks
If using AIDE, verify the configuration contains the acl option for all monitored files and directories. Here is an example AIDE configuration fragment.SampleRule = p+i+l+n+u+g+s+m+c+acl+xattrs+sha256
/bin SampleRule
If the acl option is not present, this is a finding.
If using a different file integrity tool, check the configuration per tool documentation.
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.
V-22508
No Change
Findings ID: | GEN006571 | Rule ID: | SV-26860r1_rule | Severity: | low | CCI: | CCI-001297 |
---|
Discussion
Extended attributes in file systems are used to contain arbitrary data and file metadata with security implications.System AdministratorECAT-1Checks
If using AIDE, verify the configuration contains the xattrs option for all monitored files and directories. Here is an example AIDE configuration fragment.SampleRule = p+i+l+n+u+g+s+m+c+acl+xattrs+sha256
/bin SampleRule
If the xattrs option is not present, this is a finding.
If using a different file integrity tool, check the configuration per tool documentation.
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.
V-22509
No Change
Findings ID: | GEN006575 | Rule ID: | SV-26861r1_rule | Severity: | low | CCI: | CCI-001297 |
---|
Discussion
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-1Checks
If using AIDE, verify the configuration contains the sha256 or sha512 options for all monitored files and directories. Here is an example AIDE configuration fragment.SampleRule = p+i+l+n+u+g+s+m+c+acl+xattrs+sha256
/bin SampleRule
If either the sha256 or sha512 option is not present, this is a finding.
If using a different file integrity tool, check the configuration per tool documentation.
Fix
If using AIDE, edit the configuration and add the sha256 or 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.
V-22511
No Change
Findings ID: | GEN007020 | Rule ID: | SV-38960r1_rule | Severity: | medium | CCI: | CCI-000382 |
---|
Discussion
The Stream Control Transmission Protocol (SCTP) is an 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-1Checks
Check the system to determine if SCTP is installed.# lslpp -L bos.net.\*
If the bos.net.sctp fileset is not listed, SCTP is not installed, and this is not a finding.
If the bos.net.sctp fileset is installed, ask the SA if SCTP is required for the system. If it is not, this is a finding.
Fix
If SCTP is installed and not required, unload it from the kernel and uninstall it from the system.# sctpctrl unload
Use SMIT to uninstall the bos.net.sctp fileset.
V-22530
No Change
Findings ID: | GEN007480 | Rule ID: | SV-38913r1_rule | Severity: | medium | CCI: | CCI-000382 |
---|
Discussion
The Reliable Datagram Sockets (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-1Checks
AIX has RDS protocol installed as part of the 'bos.net.tcp.client' fileset. The RDS protocol in primarily used for communication on INFI-Band interfaces. The protocol is manually loaded with the bypassctrl command.Determine if RDS is currently loaded.
#genkex | grep rds
If the RDS protocol is loaded, ask the SA if RDS is required by application software running on the system. If so, this is not applicable.
If the RDS protocol is loaded and the protocol is not used by application software, this is a finding.
Fix
Configure the system to not automatically load the RDS protocol handler.Check startup scripts for 'bypassctrl load rds' and comment out the bypassctrl commands.
Unload the driver from the kernel.
# bypassctrl unload rds
V-22544
No Change
Findings ID: | GEN007760 | Rule ID: | SV-38925r1_rule | Severity: | medium | CCI: | CCI-001551 |
---|
Discussion
Proxy Neighbor Discovery Protocol (NDP) allows a system to respond to NDP 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-1Checks
If the system does not support proxy NDP, this is not applicable.Determine if the system has proxy NDP enabled.
If IPv6 is enabled, determine if any non-local published NDP entries exist on the system.
# ndp -a
If any NDP entries contain non-local published entries, this is a finding.
Fix
Remove non-local published NDP entries from the system.# ndp -d <host>
Check system startup scripts for commands publishing NDP entries (such as "ndp -s <int> <host> <hwaddr> pub") and remove them.
V-22545
No Change
Findings ID: | GEN007780 | Rule ID: | SV-38926r1_rule | Severity: | medium | CCI: | CCI-001551 |
---|
Discussion
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-1Checks
Determine if there are any 6to4 tunnels configured on the system.#ifconfig -a
If there are any sit or cit adapters in the ifconfig listing, this is a finding.
Fix
Remove the configuration for any 6to4 tunnels on the system.#ifconfig sit0 detach
#rmdev -dl sit0
#ifconfig cit0 detach
#rmdev -dl cit0
Set the startup script /etc/rc.net to call autoconf6 with the -6 argument to prevent setting up 6 to 4 tunnels.
V-22547
No Change
Findings ID: | GEN007820 | Rule ID: | SV-38929r1_rule | Severity: | medium | CCI: | CCI-001551 |
---|
Discussion
IP tunneling mechanisms can be used to bypass network filtering.System AdministratorECSC-1Checks
Determine if any IP tunnels are configured on the system.Check for IP tunnels.
# lstun -a
# ifconfig -a | grep -e gre -e gif -e cti -e sit
If any tunnels are listed, this is a finding.
Fix
Remove the configuration for any IP tunnels from the system.Remove tunnels listed with the lstun command.
#rmtun -t <Tunnel id> -d
Remove the tunneled IP interfaces.
#ifconfig <if name> detach
#rmdev -Rdl <if name>
V-22548
No Change
Findings ID: | GEN007840 | Rule ID: | SV-38931r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
DHCP allows for the unauthenticated configuration of network parameters on the system by exchanging information with a DHCP server.System AdministratorECSC-1Checks
If the DHCP client is needed by the system, this is not applicable.Determine if the DHCP client is disabled.
# ps -ef |grep dhcpcd
If dhcpcd is running, this is a finding.
Fix
Disable the system's DHCP client.Edit /etc/rc.tcpip, comment out the line starting dhcpcd. Reboot the system to ensure the DHCP client has been disabled fully. Configure a static IP for the system, if network connectivity is required.
V-22549
No Change
Findings ID: | GEN007850 | Rule ID: | SV-38963r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
Dynamic DNS updates transmit unencrypted information about a system including its name and address and should not be used unless needed.System AdministratorECSC-1Checks
Determine if the system's DHCP client is configured to send dynamic DNS updates.#grep "^updateDNS" /etc/dhcpc.opt /etc/dhcpcd.ini
If any lines are returned, this is a finding.
Fix
Configure the system's DHCP client to not send dynamic DNS updates.Remove / comment updateDNS lines from the /etc/dhcpcd.ini and /etc/dhcpc.opt files.
V-22550
No Change
Findings ID: | GEN007860 | Rule ID: | SV-38825r1_rule | Severity: | medium | CCI: | CCI-001551 |
---|
Discussion
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-1Checks
Determine if the system is configured to ignore IPv6 ICMP redirect messages. If it is not, this is a finding.# /usr/sbin/no -o ipignoreredirects
If the value returned is not 1, this is a finding.
Fix
Configure the system to ignore IPv6 ICMP redirect messages.# /usr/sbin/no -p -o ipignoreredirects=1
V-22551
No Change
Findings ID: | GEN007880 | Rule ID: | SV-38826r1_rule | Severity: | medium | CCI: | CCI-001551 |
---|
Discussion
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 that could reveal portions of the network topology.System AdministratorECSC-1Checks
# /usr/sbin/no -o ipsendredirectsIf the value returned is not 0, this is a finding.
Fix
Configure the system to not send IPv6 ICMP redirects.# /usr/sbin/no -p -o ipsendredirects=0
V-22552
No Change
Findings ID: | GEN007900 | Rule ID: | SV-38964r1_rule | Severity: | medium | CCI: | CCI-001551 |
---|
Discussion
Reverse-path filtering provides protection against spoofed source addresses by causing the system to discard packets that have source addresses for which the system has no route or if the route does not point towards the interface on which the packet arrived. Depending on the role of the system, reverse-path filtering may cause legitimate traffic to be discarded and, therefore, should be used with a more permissive mode or filter, or not at all. Whenever possible, reverse-path filtering should be used.System AdministratorECSC-1Checks
Determine if the system is configured to use reverse-path filtering.Examine the IPSec rules on the system.
# lsfilt -a
All systems must block inbound traffic destined to the loopback address from other network interfaces.
Additionally, if the system is multihomed and the attached networks are isolated or perform symmetric routing, traffic with source addresses expected on one interface must be blocked when received on another interface.
If filtering is not configured on the system, this is a finding.
Fix
Configure the system to use reverse-path filtering using IP Sec filters.Add rules to block traffic with loopback network source addresses from being received on interfaces other than the loopback, such as other ethernet interfaces.
Use smitty or genfilt command to block loopback address from network interfaces.
# smitty ipsec6
# genfilt -v6 -a D -s <source address> -m <source netmask> -d <destination address> -M <Destination mask> -c all -o any -O any -p 0 -P 0 -w I -l y -a en0
If the system is multihomed and the attached networks are isolated or perform symmetric routing, add rules to block traffic with source addresses expected on one interface when received on another interface.
# smitty ipsec6
V-22553
No Change
Findings ID: | GEN007920 | Rule ID: | SV-38827r1_rule | Severity: | medium | CCI: | CCI-001551 |
---|
Discussion
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 IPv6 forwarding is enabled and the system is functioning as a router. System AdministratorECSC-1Checks
# /usr/sbin/no -o ip6srcrouteforwardIf the value returned is not 0, this is a finding.
Fix
Configure the system so it does not forward IPv6 source-routed packets.# /usr/sbin/no -p -o ip6srcrouteforward=0
V-22554
No Change
Findings ID: | GEN007940 | Rule ID: | SV-38828r1_rule | Severity: | medium | CCI: | CCI-001551 |
---|
Discussion
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, such as when IPv6 forwarding is enabled and the system is functioning as a router.System AdministratorECSC-1Checks
# /usr/sbin/no -o ipsrcrouterecvIf the value returned is not 0, this is a finding.
Fix
Configure the system to not accept source-routed IPv6 packets.# /usr/sbin/no -p -o ipsrcrouterecv=0
V-22556
No Change
Findings ID: | GEN008000 | Rule ID: | SV-38830r1_rule | Severity: | medium | CCI: | CCI-000185 |
---|
Discussion
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-1Checks
Check if the system is using LDAP authentication.#grep LDAP /etc/security/user
If no lines are returned, this vulnerability is not applicable.
Check if the useSSL option is enabled.
#grep '^useSSL' /etc/security/ldap/ldap.cfg
If yes is not the returned value, this is a finding.
Verify a certificate is used for client authentication to the server.
#grep -I '^ldapsslkeyf' /etc/security/ldap/ldap.cfg
If no line is found, this is a finding.
List the certificate issuer with IBM GSK.
#gsk7cmd -cert -list CA -db <certificate keyfile.kdb> -pw <Password>
Make note of the client Key Label.
#gsk7cmd -cert -details -showOID -db <certificate key.kdb> -pw <Password> -label <Key Label>
If the certificate is not issued by DoD PKI or a DoD-approved external PKI, this is a finding.
Fix
Create a key database with DoD PKI or DoD-approved certificate.#gsk7cmd
OR
#ikeyman
Edit /etc/security/ldap/ldap.conf and add or edit the ldapsslkeyf setting to reference a file containing a client certificate issued by DoD PKI or a DoD-approved external PKI.
V-22557
No Change
Findings ID: | GEN008020 | Rule ID: | SV-38966r1_rule | Severity: | medium | CCI: | CCI-000185 |
---|
Discussion
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-1Checks
Check if the system is using LDAP authentication.#grep LDAP /etc/security/user
If no lines are returned, this vulnerability is not applicable.
Verify SSL is enabled.
#grep '^useSSL' /etc/security/ldap/ldap.cfg
If yes is not the returned value, this is a finding.
Verify a server certificate is required and verified by the LDAP configuration.
#grep -I '^ldapsslkeyf' /etc/security/ldap/ldap.cfg
Make note of the key database file location.
#gsk7cmd -cert -list CA -db <certificate keyfile.kdb> -pw <Password>
Make note of the Key Label.
#gsk7cmd -cert -details -showOID -db <certificate key.kdb> -pw <Password> -label <Key Label>
THE IBM GSK Database should only have certificates for the client system and for the LDAP server.
If more certificates are in the key database than the LDAP server and the client, this is a finding.
Fix
Install a certificate signed by a DoD PKI or a DoD-approved external PKI.#gsk7cmd < or > ikeyman
Remove un-needed CA certificates.
#gsk7cmd < or > ikeyman
V-22559
No Change
Findings ID: | GEN008060 | Rule ID: | SV-38969r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the permissions of the /etc/security/ldap/ldap.cfg file.# ls -lL /etc/security/ldap/ldap.cfg
If the mode of the file is more permissive than 0644, this is a finding.
Fix
Change the permissions of the /etc/security/ldap/ldap.cfg file to 0644 or less permissive.# chmod 0644 /etc/security/ldap/ldap.cfg
V-22560
No Change
Findings ID: | GEN008080 | Rule ID: | SV-38970r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the ownership of the /etc/security/ldap/ldap.cfg file.# ls -lL /etc/security/ldap/ldap.cfg
If the file is not owned by root, this is a finding.
Fix
Change the owner of the /etc/security/ldap/ldap.cfg file.# chown root /etc/security/ldap/ldap.cfg
V-22561
No Change
Findings ID: | GEN008100 | Rule ID: | SV-38971r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the group ownership of the ldap.cfg file.Procedure:
# ls -lL /etc/security/ldap/ldap.cfg
If the file is not group-owned by bin, security, sys, or system, this is a finding.
Fix
Change the group owner of the /etc/security/ldap/ldap.cfg file to security, bin, sys, or system.Procedure:
# chgrp security /etc/security/ldap/ldap.cfg
V-22562
No Change
Findings ID: | GEN008120 | Rule ID: | SV-38972r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the permissions of the /etc/security/ldap/ldap.cfg file.Procedure:
# aclget /etc/security/ldap/ldap.cfg
Check to see if extended permissions are enabled.
If extended permissions are enabled, this is a finding.
Fix
Remove the extended ACL from the /etc/security/ldap/ldap.cfg file.# acledit /etc/security/ldap/ldap.cfg
Disable extended file permissions.
V-22563
No Change
Findings ID: | GEN008140 | Rule ID: | SV-38973r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Determine the SSL Certificate database file and/or directory.# grep -i '^ldapsslkeyf' /etc/security/ldap/ldap.cfg
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
Change the ownership of the SSL key database file or directory.# chown root <certpath>
V-22564
No Change
Findings ID: | GEN008160 | Rule ID: | SV-38974r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Check the group ownership of the SSL key database file.Determine the location of the SSL key database.
# grep -i '^ldapsslkeyf' /etc/security/ldap/ldap.cfg
Check the group ownership of the SSL key database file.
# ls -lLa <ldap certificate file(s) or directories>
If a certificate file or directory is not group-owned by root, bin, security, sys, or system, this is a finding.
Fix
Change the group ownership of LDAP client SSL certificate database file to root, security, bin, sys, or system.Procedure:
# chgrp system < certificate file >
V-22565
No Change
Findings ID: | GEN008180 | Rule ID: | SV-38975r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Determine the SSL certificate key database file and/or directory.Procedure:
# grep -i '^ldapsslkeyf' /etc/security/ldap/ldap.cfg
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
Change the mode of the file to 0644 or the directory to 0755 or less permissive.File Procedure:
# chmod 0644 < SSL key database certpath >
Directory Procedure:
# chmod 0755 < SSL key database certpath >
V-22566
No Change
Findings ID: | GEN008200 | Rule ID: | SV-38976r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
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-1Checks
Determine the SSL certificate key database file and/or directory.# grep -i '^ldapsslkeyf' /etc/security/ldap/ldap.cfg
For each file or directory returned, check the permissions.
# aclget < certpath >
# aclget < certpath >/< certfile >
If extended file permissions are enabled, this is a finding.
Fix
Remove the extended ACL from the SSL certificate key database file.# acledit < certpath >
# acledit < certpath >/<certfile >
Disable the extended file permissions.
V-22576
No Change
Findings ID: | GEN008420 | Rule ID: | SV-38831r1_rule | Severity: | low | CCI: | CCI-000366 |
---|
Discussion
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-1Checks
Running the sedmgr command without any options will show the settings currently in effect.#sedmgr
If the value returned for the sedmgr mode is off, this is a finding.
Fix
Configure the system to use any available memory address randomization techniques. Recommended settings are either to enable stack execution disablement for all suid files or select system executables.Set sedmgr to enforce on selected files and terminate processes violating stack execution boundaries.
# sedmgr -m select -o off
OR
Set sedmgr to enforce on setid files and terminate processes violating stack execution boundaries.
# sedmgr -m setidfiles -o off
After a global system change to the sed, the system should be rebooted.
# shutdown -Fr
V-22577
No Change
Findings ID: | GEN008440 | Rule ID: | SV-38832r1_rule | Severity: | low | CCI: | CCI-000366 |
---|
Discussion
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 AdministratorECSC-1Checks
Determine if the system uses automated file system mounting tools (such as autofs or automount). AIX can use automount facility.#ps -ef | grep -v grep | grep automount
If the automount process is running, this is a finding.
Fix
Disable the automated file system mounting tools.Empty the /etc/auto_master file
kill automount
kill < pid of automount >
V-22578
No Change
Findings ID: | GEN008460 | Rule ID: | SV-38833r1_rule | Severity: | low | CCI: | CCI-000366 |
---|
Discussion
USB is a common computer peripheral interface. USB devices may include storage devices that could be used to install malicious software on a system or exfiltrate data.trueSystem AdministratorECSC-1Checks
AIX has server USB drivers installed, such as keyboard, mount, and mass media drivers.Determine if the system has USB enabled.
# lsdev -C | grep usb
# lslpp -l | grep usb
If usb filesets are installed on the system, USB is enabled and this is a finding.
Fix
Disable USB devices on the system. Use SMIT to remove the following filesets.devices.usbif.*
# smitty remove
V-22579
No Change
Findings ID: | GEN008480 | Rule ID: | SV-38834r1_rule | Severity: | low | CCI: | CCI-000366 |
---|
Discussion
USB is a common computer peripheral interface. USB devices may include storage devices that could be used to install malicious software on a system or exfiltrate data.trueSystem AdministratorECSC-1Checks
If the system uses USB mass storage, this is not applicable.# lslpp -l | grep -e devices.usbif.010100 -e devices.usbif.08025 -e devices.usbif.080400
If these filesets are installed on the system, USB mass storage is enabled and this is a finding.
Fix
Disable USB mass storage on the system by using SMIT to remove the following filesets.devices.usbif.010100
devices.usbif.08025002
devices.usbif.080400
# smitty remove
V-22582
No Change
Findings ID: | GEN008520 | Rule ID: | SV-38961r1_rule | Severity: | medium | CCI: | CCI-001118 |
---|
Discussion
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-1Checks
Determine if the system is using a local firewall.# lsfilt
# smitty ipsec4
If local firewall is not configured and running, this is a finding.
Fix
Configure the system to use a local firewall.Use SMIT to load the IPSEC filesets.
#smit install
Use SMIT to configure filters.
#smit ipsec4
V-22583
No Change
Findings ID: | GEN008540 | Rule ID: | SV-38985r1_rule | Severity: | medium | CCI: | CCI-001109 |
---|
Discussion
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-1Checks
Determine if the system's local firewall implements a deny-all, allow-by-exception policy.View the firewall (filter rules) with smit or lsfilt commands.
# smitty ipsec4
# lsfilt
If there is not a deny-all, allow-by-exception policy, this is a finding.
Fix
Configure the system's local firewall to implement a deny-all,allow-by-exception policy.
Firewall rules can be added and activated with SMIT ipsec4 or genfilt command.
#smitty ipsec4
V-22665
No Change
Findings ID: | GEN005590 | Rule ID: | SV-38923r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
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-1Checks
Check for any running routing protocol daemons.# ps -ef | egrep '(ospf|route|bgp|zebra|quagga|gate)'
If any routing protocol daemons are listed, this is a finding.
Fix
Disable any routing protocol daemons.
V-22702
No Change
Findings ID: | GEN002690 | Rule ID: | SV-38902r1_rule | Severity: | medium | CCI: | CCI-000162 |
---|
Discussion
Sensitive system and user information could provide a malicious user with enough information to penetrate further into the system.System AdministratorECLP-1, ECTP-1Checks
Procedure:# grep -p bin: /etc/security/audit/config
Directories to search will be listed under the bin stanza.
# ls -la <audit directories>
If any audit log file is not group-owned by bin, sys, or system, this is a finding.
Fix
Change the group ownership of the audit log file(s). Procedure:# chgrp system < audit log file >
V-23732
No Change
Findings ID: | GEN000410 | Rule ID: | SV-38934r1_rule | Severity: | medium | CCI: | CCI-000048 |
---|
Discussion
Failure to display the login 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 and should be used in place of FTP. SFTP is implemented by the SSH service and uses its banner configuration.System AdministratorECWM-1
Checks
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
Configure the system to display one of the DoD login banners (based on the character limitations imposed by the system) prior to any FTP login attempt.Add a banner file to the system with the DoD login banner.
#vi /etc/herald
<Add DoD banner to file>
#chmod 644 /etc/herald
#chown root:system /etc/herald
Add a herald line to the /etc/ftpaccess.ctl file.
#vi /etc/ftpaccess.ctl
<add/update line in /etc/ftpaccess.ctl> herald: /etc/herald
#chown root:system /etc/ftpaccess.ctl
#chmod 640 /etc/ftpaccess.ctl
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."
V-23736
No Change
Findings ID: | GEN003621 | Rule ID: | SV-38871r1_rule | Severity: | low | CCI: | CCI-001208 |
---|
Discussion
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-1Checks
Determine if the /var path is a separate file system.# df -k /var
If /var is not on its own file system, this is a finding.
Fix
Migrate the /var path onto a separate file system.
V-23738
No Change
Findings ID: | GEN003623 | Rule ID: | SV-38872r1_rule | Severity: | low | CCI: | CCI-001208 |
---|
Discussion
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-1Checks
Determine the location of the audit data path.#more /etc/security/audit/config
Make note of the binfile and trail location.
(The best practice is to have the audit data and trails sent to /audit.)
# cd < audit path >
#df -k .
If the system audit data path is not on a separate file system, this is a finding.
Fix
Migrate the system audit data path onto a separate file system.Update the /etc/security/audit/config file as necessary to reflect the location of the audit data.
V-23739
No Change
Findings ID: | GEN003624 | Rule ID: | SV-39505r1_rule | Severity: | low | CCI: | CCI-001208 |
---|
Discussion
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-1Checks
Determine if the /tmp path is a separate file system.# df -k /tmp
If /tmp is not its own file system, this is a finding.
Fix
Migrate the /tmp path onto a separate file system.
V-23741
No Change
Findings ID: | GEN003601 | Rule ID: | SV-38796r1_rule | Severity: | medium | CCI: | CCI-000366 |
---|
Discussion
To provide some mitigation to TCP DoS attacks, the clear_partial_conns parameter must be enabled.System AdministratorECSC-1Checks
# /usr/sbin/no -o clean_partial_connsIf the value returned is 0, this is a finding.
Fix
# /usr/sbin/no -po clean_partial_conns=1
V-23952
No Change
Findings ID: | GEN004710 | Rule ID: | SV-38919r1_rule | Severity: | medium | CCI: | CCI-001305 |
---|
Discussion
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 AdministratorECSC-1Checks
If the system uses Sendmail, locate the sendmail.cf file.Procedure:
# find / -name sendmail.cf
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:
# find / -name sendmail.mc
# grep -i promiscuous_relay </path/to/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 that mail relaying is restricted.
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.
V-23953
No Change
Findings ID: | GEN007960 | Rule ID: | SV-28909r1_rule | Severity: | medium | CCI: | CCI-000305 |
---|
Discussion
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 preventing 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 AdministratorECSC-1
Checks
Consult vendor documentation concerning the ldd command. If the command provides protection from the execution of untrusted executables, this is not a finding.Determine the location of the system's ldd command.
Procedure:
# find / -name ldd
If no file exists, this is not a finding.
Check the permissions of the found ldd file.
# ls -lL <path to ldd>
If the file mode of the file is more permissive than 0000, this is a finding.
Fix
Disable the ldd command by removing its permissions.Procedure:
# chmod 0000 <path to ldd>
V-23972
No Change
Findings ID: | GEN007950 | Rule ID: | SV-38829r1_rule | Severity: | medium | CCI: | CCI-000366 |
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Discussion
Responding to broadcast ICMP echo requests facilitates network mapping and provides a vector for amplification attacks.System AdministratorECSC-1Checks
# /usr/sbin/no -o bcastpingIf the value returned is not 0, this is a finding.
Fix
Configure the system to not respond to IPv6 multicast ICMP ECHO_REQUESTs.# /usr/sbin/no -p -o bcastping=0
V-24331
No Change
Findings ID: | GEN000402 | Rule ID: | SV-38933r1_rule | Severity: | medium | CCI: | CCI-000048 |
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Discussion
Failure to display the login 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
Access the graphical desktop environment(s) provided by the system and attempt to logon. 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
Edit the Xresources file to configure the system to display one of the DoD login banners (based on the character limitations imposed by the system) prior to, or as part of, the graphical desktop environment login process.For Dt login, change the variable Dtlogin*greeting.labelString: in Xresources file.
#cp /usr/dt/config/C/Xresources /etc/dt/config/C/Xresources
#vi /etc/dt/config/C/Xresources
For XDM login, change the variable Xlogin*greeting in the Xresources file.
#vi /usr/lpp/X11/lib/X11/xdm/Xresources.
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."
V-24347
No Change
Findings ID: | GEN009120 | Rule ID: | SV-39317r2_rule | Severity: | medium | CCI: | CCI-000768 |
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Discussion
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 with 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
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
Consult IBM documentation to determine the procedures necessary for configuring CAC authentication through PKI. Configure all accounts required by policy to use CAC authentication.
V-24357
No Change
Findings ID: | GEN002870 | Rule ID: | SV-38859r1_rule | Severity: | low | CCI: | CCI-000136 |
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Discussion
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 AdministratorECTB-1
Checks
Ask the SA to provide information on the remote logging of audit records. Verify the configuration described is functioning. If no method of remote logging of audit records is in place or functioning, this is a finding.Methods of remote audit record logging will be site-specific and may depend on the use of third-party tools. One possible method with AIX is the use of the audit streams facility such as:
Verify "streammode = on" in /etc/security/audit/config.
Check that /etc/security/audit/streamcmds sends stream logs to the syslog facility with an entry such as:
/usr/sbin/auditstream | auditpr -v | /usr/bin/logger -p local7.info &
Check that the /etc/syslog.conf file is configured to send local7.info to a remote server with an entry such as:
local7.info @logserver
Fix
Configure the system to send audit records to a remote system. The actual method is left to site discretion and may involve the use of third-party products.One method for performing remote audit logging involves streaming audit records to syslog and using syslog to send the records to another system.
Enable stream mode by editing the /etc/security/audit/config and set streammode = on.
Edit /etc/security/audit/streamcmds to send stream logs to the syslog facility with an entry such as:
/usr/sbin/auditstream | auditpr -v | /usr/bin/logger -p local7.info &
Edit the /etc/syslog.conf file to configure syslog to send local7.info to a remote server with an entry such as:
Local7.info @logserver
V-24384
No Change
Findings ID: | GEN008050 | Rule ID: | SV-38968r1_rule | Severity: | medium | CCI: | CCI-000196 |
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Discussion
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 AdministratorIAIA-1, IAIA-2Checks
Examine the LDAP configuration file(s).#grep bindpwd: /etc/security/ldap/ldap.cfg
If the returned entry has an unencrypted password (not like "bindpwd:{DES}"), this is a finding.
If the LDAP configuration file contains an encrypted password accessible by regular users on the system, this is a finding.
#ls -l /etc/security/ldap/ldap.cfg
Check for unencrypted SSL keyfile password.
#grep '^ldapsslkeypwd' /etc/security/ldap/ldap.cfg
If the returned entry has an unencrypted password (not like "ldapsslkeypwd:{DES}"), this is a finding.
Fix
Remove any passwords from LDAP configuration files.The bindpw (bind password) can be encrypted with the mksecldap command.
#mksecldap
Stash the SSL key database file with the gsk7cmd or ikeyman commands.
#gsk7cmd < or > ikeyman
Comment out the ldapsslpwd line to use stashed password. The password stash file must reside in the same directory as the SSL key database, and must have the same name as the key database, but with an extension of .sth instead of .kdb.
V-24386
No Change
Findings ID: | GEN003850 | Rule ID: | SV-38953r1_rule | Severity: | high | CCI: | CCI-000197 |
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Discussion
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-1Checks
Consult vendor documentation to determine the method for determining if the telnet daemon is running. If the system uses inetd, use the following procedure.# grep -v '^#' /etc/inetd.conf | grep telnet
If an entry is returned, the telnet daemon is running.
If the telnet daemon is running, this is a finding.
Fix
Edit the /etc/inetd.conf file and comment out the telnet line.Reload the inetd process.
# refresh -s inetd
V-29491
No Change
Findings ID: | GEN000000-AIX0085 | Rule ID: | SV-38695r1_rule | Severity: | medium | CCI: | CCI-000225 |
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Discussion
The /etc/netsvc.conf file is used to specify the ordering of name resolution for the sendmail command, alias resolution for the sendmail command, and host name resolution routines. Malicious changes could prevent the system from functioning correctly or compromise system security.System AdministratorECLP-1Checks
Verify the /etc/netsvc.conf file is owned by root.# ls -l /etc/netsvc.conf
If the file is not owned by root, this is a finding.
Fix
Change the owner of the /etc/netsvc.conf file to root.# chown root /etc/netsvc.conf
V-29492
No Change
Findings ID: | GEN000000-AIX0090 | Rule ID: | SV-38696r1_rule | Severity: | medium | CCI: | CCI-000225 |
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Discussion
The /etc/netsvc.conf file is used to specify the ordering of name resolution for the sendmail command, alias resolution for the sendmail command, and host name resolution routines. Malicious changes could prevent the system from functioning correctly or compromise system security.System AdministratorECLP-1Checks
Check the group ownership of the /etc/netcsvc.conf file.Procedure:
# ls -lL /etc/netsvc.conf
If the file is not group-owned by bin, sys, or system, this is a finding.
Fix
Change the group owner of the /etc/netsvc.conf file to bin, sys, or system.Procedure:
# chgrp system /etc/netsvc.conf
V-29493
No Change
Findings ID: | GEN000000-AIX0100 | Rule ID: | SV-38697r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
The /etc/netsvc.conf file is used to specify the ordering of name resolution for the sendmail command, alias resolution for the sendmail command, and host name resolution routines. Malicious changes could prevent the system from functioning correctly or compromise system security.System AdministratorECLP-1Checks
Check the mode of the /etc/netsvc.conf file.# ls -l /etc/netsvc.conf
If the file mode is more permissive than 0644, this is a finding.
Fix
Change the mode of the /etc/netsvc.conf file to 0644 or less permissive.# chmod 0644 /etc/netsvc.conf
V-29494
No Change
Findings ID: | GEN000000-AIX0110 | Rule ID: | SV-38698r1_rule | Severity: | medium | CCI: | CCI-000225 |
---|
Discussion
The /etc/netsvc.conf file is used to specify the ordering of name resolution for the sendmail command, alias resolution for the sendmail command, and host name resolution routines. Malicious changes could prevent the system from functioning correctly or compromise system security.System AdministratorECLP-1Checks
Verify there is no extended ACL on the /etc/netsvc.conf file.# aclget /etc/netsvc.conf
If extended permissions are enabled, this is a finding.
Fix
Remove the extended ACL from the /etc/nsswitch.conf file and disable extended permissions.#acledit /etc/netsvc.conf
V-29495
No Change
Findings ID: | GEN000000-AIX0200 | Rule ID: | SV-38699r1_rule | Severity: | medium | CCI: | CCI-000032 |
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Discussion
Disabling directed broadcast prevents packets directed to a gateway to be broadcasted on a remote network.System AdministratorECSC-1Checks
Check the directed_broadcast option.# /usr/sbin/no -o directed_broadcast
If the value returned is not 0, this is a finding.
Fix
Configure directed_broadcast to 0.# /usr/sbin/no -p -o directed_broadcast=0
V-29496
No Change
Findings ID: | GEN000000-AIX0210 | Rule ID: | SV-38700r1_rule | Severity: | medium | CCI: | CCI-000032 |
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Discussion
The ICMP attacks may be of the form of ICMP source quench attacks and Path MTU Discovery (PMTUD) attacks. If this network option tcp_icmpsecure is turned on, the system does not react to ICMP source quench messages. This will protect against ICMP source quench attacks. The payload of the ICMP message is tested to determine if the sequence number of the TCP header portion of the payload is within the range of acceptable sequence numbers. This will mitigate PMTUD attacks to a large extent.System AdministratorECSC-1
Checks
Check the value of the tcp_icmpsecure parameter.# /usr/sbin/no -o tcp_icmpsecure
If the value returned is not 1, this is a finding.
Fix
Set the tcp_icmpsecure parameter to 1.# /usr/sbin/no -p -o tcp_icmpsecure=1
V-29497
No Change
Findings ID: | GEN000000-AIX0220 | Rule ID: | SV-38701r1_rule | Severity: | medium | CCI: | CCI-000032 |
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Discussion
The tcp_tcpsecure parameter provides protection for TCP connections from fake SYN's, fake RST, and data injections on established connections. The first vulnerability involves sending a fake SYN to an established connection to abort the connection. The second vulnerability involves sending a fake RST to an established connection to abort the connection. The third vulnerability involves injecting fake data in an established TCP connection.System AdministratorECSC-1Checks
Check the value of the tcp_tcpsecure parameter.# /usr/sbin/no -o tcp_tcpsecure
If the value returned is not 7, this is a finding.
Fix
Set the tcp_tcpsecure parameter to 7.# /usr/sbin/no -p -o tcp_tcpsecure=7
V-29498
No Change
Findings ID: | GEN000000-AIX0230 | Rule ID: | SV-38702r1_rule | Severity: | medium | CCI: | CCI-000032 |
---|
Discussion
The parameter ip_nfrag provides an additional layer of protection against IP fragmentation attacks. The value the ip_nfrag specifies is the maximum number of fragments of an IP packet that can be kept in the IP reassembly queue at any time. The default value of this network option is 200. This is a reasonable value for most environments and offers protection from IP fragmentation attacks. System AdministratorECSC-1Checks
Check the value of the ip_nfrag parameter.# /usr/sbin/no -o ip_nfrag
If the result returned is less than 200, this is a finding.
Fix
Set the ip_nfrag parameter to 200.# /usr/sbin/no -p -o ip_nfrag=200
V-29499
No Change
Findings ID: | GEN000000-AIX0300 | Rule ID: | SV-38703r1_rule | Severity: | medium | CCI: | CCI-000032 |
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Discussion
The bootp service is used for Network Installation Management (NIM) and remote booting of systems. The bootp service should not be active unless it is needed for NIM servers or booting remote systems. Running unnecessary services increases the attack vector of the system.System AdministratorECSC-1Checks
Check the /etc/inetd.conf file for active bootp service.# grep bootp /etc/inetd.conf |grep -v \#
If the bootp service is not disabled, this is a finding.
Fix
Disable the bootp service from /etc/inetd.conf.Edit /etc/inetd.conf and comment out bootp service line.
Restart the inetd service.
#refresh -s inetd
V-29500
No Change
Findings ID: | GEN009140 | Rule ID: | SV-38704r1_rule | Severity: | medium | CCI: | CCI-001436 |
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Discussion
When contacted, chargen responds with some random characters. When contacted via UDP, itwill respond with a single UDP packet. When contacted via TCP, it will continue spewing characters until the client closes the connection. An easy attack is 'ping-pong' in which an attacker spoofs a packet between two machines running chargen. This will cause them to spew characters at each other, slowing the machines down and saturating the network.
The chargen service is unnecessary and provides an opportunity for Denial of Service attack. System AdministratorECSC-1
Checks
Check the /etc/inetd.conf file for active TCP and UDP chargen service entries.# grep chargen /etc/inetd.conf |grep -v \#
If the chargen service is enabled, this is a finding.
Fix
Edit /etc/inetd.conf and comment out the chargen service line for both udp and tcp protocols.Restart the inetd service.
#refresh -s inetd
V-29501
No Change
Findings ID: | GEN009160 | Rule ID: | SV-38705r1_rule | Severity: | medium | CCI: | CCI-001436 |
---|
Discussion
The CMSD service for CDE is an unnecessary process that runs a root and increases attack vector of the system. Buffer overflow attacks against the CMSD process can potentially give access to the system.System AdministratorECSC-1Checks
Check the /etc/inetd.conf file for active CMSD service.# grep 'rpc\.cmsd' /etc/inetd.conf |grep -v \#
If the CMSD service is enabled, this is a finding.
Fix
Edit /etc/inetd.conf and comment out the CMSD service.Restart the inetd service.
# refresh -s inetd
V-29502
No Change
Findings ID: | GEN009180 | Rule ID: | SV-38706r1_rule | Severity: | medium | CCI: | CCI-001436 |
---|
Discussion
The ttdbserver service for CDE is an unnecessary service that runs as root and might be compromised.System AdministratorECSC-1Checks
Check the /etc/inetd.conf file for active ttdbserver service.# grep 'rpc\.ttdbserver' /etc/inetd.conf |grep -v \#
If the ttdbserver service is enabled, this is a finding.
Fix
Edit /etc/inetd.conf and comment out ttdbserver service line.Restart the inetd service.
# refresh -s inetd
V-29503
No Change
Findings ID: | GEN009190 | Rule ID: | SV-38707r1_rule | Severity: | medium | CCI: | CCI-001436 |
---|
Discussion
The comsat daemon notifies users on incoming email. This is an unnecessary service and is vulnerable to a flood attack. Running unnecessary services increases the attack vector of the system.System AdministratorECSC-1Checks
Check the /etc/inetd.conf file for active comsat service.#grep comsat /etc/inetd.conf | grep -v \#
If the comsat service is enabled, this is a finding.
Fix
Edit /etc/inetd.conf and comment out comsat service line. Restart the inetd service.# refresh -s inetd
V-29504
No Change
Findings ID: | GEN009200 | Rule ID: | SV-38708r1_rule | Severity: | medium | CCI: | CCI-001436 |
---|
Discussion
The daytime service runs as root from the inetd daemon and can provide an opportunity for Denial of Service PING or PING-PONG attacks. The daytime service is unnecessary and it increases the attack vector of the system.System AdministratorECSC-1Checks
Check the /etc/inetd.conf file for TCP and UDP daytime service.#grep daytime /etc/inetd.conf | grep -v \#
If the daytime service is enabled, this is a finding.
Fix
Edit /etc/inetd.conf and comment out daytime service lines for both TCP and UDP protocols.Restart the inetd service.
# refresh -s inetd
V-29505
No Change
Findings ID: | GEN009210 | Rule ID: | SV-38709r1_rule | Severity: | medium | CCI: | CCI-001436 |
---|
Discussion
The discard service runs as root from the inetd server and can be used in Denial of Service attacks. The discard service is unnecessary and it increases the attack vector of the system.System AdministratorECSC-1Checks
Check the /etc/inetd.conf file for TCP and UDP discard service entries.#grep discard /etc/inetd.conf | grep -v \#
If the discard service is active, this is a finding.
Fix
Edit /etc/inetd.conf and comment out the discard service line for both TCP and UDP protocols.Restart the inetd service.
#refresh -s inetd
V-29506
No Change
Findings ID: | GEN009220 | Rule ID: | SV-38710r1_rule | Severity: | medium | CCI: | CCI-001436 |
---|
Discussion
This service is started automatically by the inetd daemon with root permission in response to a CDE client requesting a process to be started on the daemon’s host system. Running the dtscp service is unnecessary and it increases the attack vector of the system.System AdministratorECSC-1Checks
Check the /etc/inetd.conf for the dtspc service.#grep dtspcd /etc/inetd.conf | grep -v \#
If the dtspc service is enabled, this is a finding.
Fix
Edit /etc/inetd.conf and comment out dtspc service line.Restart the inetd service.
# refresh -s inetd
V-29507
No Change
Findings ID: | GEN009230 | Rule ID: | SV-38711r1_rule | Severity: | medium | CCI: | CCI-001436 |
---|
Discussion
The echo service can be used in Denial of Service or SMURF attacks. It can also used at someone else to get through a firewall or start a data storm. The echo service is unnecessary and it increases the attack vector of the system.System AdministratorECSC-1Checks
Check the /etc/inetd.conf for TCP and UDP echo service entries.#grep echo /etc/inetd.conf | grep -v \#
If the echo service is enabled, this is a finding.
Fix
Edit /etc/inetd.conf and comment out the echo service lines for both TCP and UDP.Restart the inetd service.
# refresh -s inetd
V-29508
No Change
Findings ID: | GEN009240 | Rule ID: | SV-38712r1_rule | Severity: | medium | CCI: | CCI-001436 |
---|
Discussion
The IMAP service should not be running unless the system is acting as a mail server for client connections. Running unnecessary services increases the attack vector on the system.System AdministratorECSC-1Checks
Check the /etc/inetd.conf file for active IMAP service.#grep imapd /etc/inetd.conf | grep -v \#
If the IMAP service is enabled, this is a finding.
Fix
Edit /etc/inetd.conf and comment out the imap2 service line.Restart the inetd service.
# refresh -s inetd
V-29509
No Change
Findings ID: | GEN009250 | Rule ID: | SV-38713r1_rule | Severity: | medium | CCI: | CCI-001436 |
---|
Discussion
The POP3 service is only needed if the server is acting as a mail server and clients are using applications that only support POP3. Users' ids and passwords are sent in plain text to the POP3 service. If mail client access is needed, consider using IMAP or SSL enabled POP3.System AdministratorECSC-1Checks
Check the '/etc/inetd.conf' file for active POP3 service.#grep pop3 /etc/inetd.conf | grep -v \#
If the POP3 service is enabled, this is a finding.
Fix
Edit /etc/inetd.conf and comment out POP3 the service line. Restart the inetd service.# refresh -s inetd
V-29510
No Change
Findings ID: | GEN009260 | Rule ID: | SV-38714r1_rule | Severity: | medium | CCI: | CCI-001436 |
---|
Discussion
The talk and ntalk commands allow users on the same or different systems on converse. The talk daemons are started from the inetd process and run as root. These unnecessary processes increase the attack vector of the system and may cause Denial of Service by scrambling the users display. System AdministratorECSC-1Checks
Check the /etc/inetd.conf file for talk and ntalk services.#grep talk /etc/inetd.conf | grep -v \#
If any TCP or UDP talk or ntalk services are enabled, this is a finding.
Fix
Edit /etc/inetd.conf and comment out TCP and UDP for the talk service.Edit /etc/inetd.conf and comment out TCP and UDP for the ntalk service.
Restart the inetd service.
# refresh -s inetd
V-29511
No Change
Findings ID: | GEN009270 | Rule ID: | SV-38715r1_rule | Severity: | medium | CCI: | CCI-001436 |
---|
Discussion
The netstat service can potentially give out network information on active connections if it is running. The information given out can aid in an attack and weaken the systems defensive posture.System AdministratorECSC-1Checks
Check the /etc/inetd.conf for active netstat service.grep netstat /etc/inetd.conf | grep -v \#
If the netstat service is active, this is a finding.
Fix
Edit /etc/inetd.conf and comment out the netstat service line.Restart the inetd service.
# refresh -s inetd
V-29512
No Change
Findings ID: | GEN009280 | Rule ID: | SV-38716r1_rule | Severity: | medium | CCI: | CCI-001436 |
---|
Discussion
The PCNFS service predates Microsoft’s SMB specifications. If a similar service is needed to share files from a Windows based OS to a UNIX based OS, consider SAMBA.System AdministratorECSC-1Checks
Check the /etc/inetd.conf file for active PCNFS service.#grep pcnfsd /etc/inetd.conf | grep -v \#
If the PCNFS service is enabled, this is a finding.
Fix
Edit /etc/inetd.conf and comment out the PCNFS service line. Restart the inetd service.# refresh -s inetd
V-29513
No Change
Findings ID: | GEN009290 | Rule ID: | SV-38717r1_rule | Severity: | medium | CCI: | CCI-001436 |
---|
Discussion
The systat daemon allows remote users to see the running process and who is running them. This may aid in information collection for an attack and weaken the security posture of the system.System AdministratorECSC-1Checks
Check the /etc/inetd.conf file for active systat service.#grep systat /etc/inetd.conf | grep -v \#
If the systat service is enabled, this is a finding.
Fix
Edit /etc/inetd.conf and comment out systat the service line.Restart the inetd service.
# refresh -s inetd
V-29514
No Change
Findings ID: | GEN009300 | Rule ID: | SV-38718r1_rule | Severity: | medium | CCI: | CCI-001436 |
---|
Discussion
The time service is an internal inetd function is used by the rdate command. This service is sometimes used to synchronize clocks at boot time. The service is outdated. Use the ntpdate command instead.System AdministratorECSC-1Checks
Check the /etc/inetd.conf file for TCP and UDP time service.grep time /etc/inetd.conf | grep -v daytime | grep -v \#
If the time service is enabled, this is a finding.
Fix
Edit the /etc/inetd.conf file and comment out the time service line.Restart the inetd service.
# refresh -s inetd
V-29515
No Change
Findings ID: | GEN009310 | Rule ID: | SV-38719r1_rule | Severity: | medium | CCI: | CCI-001436 |
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Discussion
The rusersd daemon gives out a list of current uses on the system. The rusersd daemon is unnecessary and it increases the attack vector of the system by providing information on the current users of the system.System AdministratorECSC-1Checks
Check the /etc/inetd.conf file for active rusersd service.#grep rusersd /etc/inetd.conf | grep -v \#
If the rusersd service is enabled, this is a finding.
Fix
Edit the /etc/inetd.conf file and comment out the rusersd service line.Restart the inetd service.
# refresh -s inetd
V-29516
No Change
Findings ID: | GEN009320 | Rule ID: | SV-38720r1_rule | Severity: | medium | CCI: | CCI-001436 |
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Discussion
The sprayd service is sometimes used for network and nfs troubleshooting. The spray service can be used for both buffer overflow and Denial of Service attacks by saturating the network. The sprayd daemon is an unnecessary service.System AdministratorECSC-1Checks
Check the /etc/inetd.conf file for active sprayd service.# grep sprayd /etc/inetd.conf | grep -v \#
If the sprayd service is enabled, this is a finding.
Fix
Edit the /etc/inetd.conf file and comment out the sprayd service line.Restart the inetd service.
# refresh -s inetd
V-29517
No Change
Findings ID: | GEN009330 | Rule ID: | SV-38721r1_rule | Severity: | medium | CCI: | CCI-001436 |
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Discussion
The rstatd can give out information on the running system, such as the CPU usage, the system uptime, its network usage, and other system information that could potentially aid in an attack. The rstatd service is unnecessary and it weakens the defensive posture of the system. If systems monitoring is needed, use a third party tool or SNMP. System AdministratorECSC-1Checks
Check the /etc/inetd.conf file for active rstatd service.#grep rstatd /etc/inetd.conf | grep -v \#
If the rstatd service is enabled, this is a finding.
Fix
Edit the /etc/inetd.conf file and comment out the rstatd service line.Restart the inetd service.
# refresh -s inetd
V-29518
No Change
Findings ID: | GEN009340 | Rule ID: | SV-38722r1_rule | Severity: | medium | CCI: | CCI-001436 |
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Discussion
Running Xservers and X-login managers when not needed for X11 session management increases the attack vector of the system by running unnecessary services.System AdministratorECSC-1Checks
Check to see if X display login managers are running.#cat /etc/inittab | grep -e /etc/rc.dt -e xdm
If any X server login managers are running, ask the SA if they are necessary for the operation of the system.
If there is unnecessary X server login managers running, this is a finding.
Fix
Comment out or remove the X login servers from the /etc/inittab file.#vi /etc/inittab
Refresh the init process.
# init q
V-29519
No Change
Findings ID: | GEN000000-AIX0310 | Rule ID: | SV-38750r1_rule | Severity: | medium | CCI: | CCI-000032 |
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Discussion
The ftpaccess.ctl file contains options for the ftp daemon, such as herald, motd, user access, and permissions to files and directories. If the ftpaccess.ctl file does not exist, the ftpd process will not display any warning banners, and permissions will only be enforced using basic UNIX permissions. System AdministratorECSC-1Checks
Check for the existence of the /etc/ftpaccess.ctl file.# ls -l /etc/ftpaccess.ctl
If the ftpaccess.ctl file does not exist, this is a finding.
Fix
Create a /etc/ftpaccess.ctl file.#touch /etc/ftpaccess.ctl
Add at least the herald: /path to login banner to the /etc/ftpaccess.ctl file.
#vi /etc/ftpaccess.ctl
V-29520
No Change
Findings ID: | GEN000000-AIX0320 | Rule ID: | SV-38751r1_rule | Severity: | medium | CCI: | CCI-000225 |
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Discussion
If the ftpaccess.ctl file is not owned by root, an unauthorized user may modify the file to allow unauthorized access to change the file. Unauthorized modification could result in Denial of Service to authorized FTP users or permit unauthorized access to system information.System Administrator
Checks
Check the ownership of the /etc/ftpaccess.ctl file.# ls -l /etc/ftpaccess.ctl
If the ftpaccess.ctl file is not owned by root, this is a finding.
Fix
Change the owner of the ftpaccess.ctl file to root.# chown root /etc/ftpaccess.ctl
V-29521
No Change
Findings ID: | GEN000000-AIX0330 | Rule ID: | SV-38752r1_rule | Severity: | medium | CCI: | CCI-000225 |
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Discussion
If the ftpaccess.ctl file is not group-owned by a system group, an unauthorized user may modify the file to allow unauthorized access to modify the file. Unauthorized modification could result in Denial of Service to authorized FTP users or permit unauthorized access to system information.System AdministratorECLP-1Checks
Check the group ownership of the ftpaccess.ctl file.# ls -lL /etc/ftpaccess.ctl
If the /etc/ftpaccess.ctl file is not group-owned by bin, sys, or system, this is a finding.
Fix
Change the group owner of the /etc/ftpaccess.ctl file.# chgrp system /etc/ftpaccess.ctl
V-29522
No Change
Findings ID: | GEN000000-AIX0340 | Rule ID: | SV-38753r1_rule | Severity: | medium | CCI: | CCI-000225 |
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Discussion
Excessive permissions on the ftpaccess.ctl file could permit unauthorized modification. Unauthorized modification could result in Denial of Service to authorized FTP users or permit unauthorized access to system information.System AdministratorECLP-1Checks
Check the permissions of the /etc/ftpaccess.ctl file.# ls -l /etc/ftpaccess.ctl
If the ftpaccess.ctl file has a mode more permissive than 0640, this is a finding.
Fix
Change the mode of the /etc/ftpaccess.ctl file to 0640.# chmod 0640 /etc/ftpaccess.ctl
V-29523
No Change
Findings ID: | GEN000000-AIX0350 | Rule ID: | SV-38754r1_rule | Severity: | medium | CCI: | CCI-000225 |
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Discussion
Excessive permissions on the ftpaccess.ctl file could permit unauthorized modification. Unauthorized modification could result in Denial of Service to authorized FTP users or permit unauthorized access to system information.System AdministratorECLP-1Checks
Check the permissions of the /etc/ftpaccess.ctl file.#aclget /etc/ftpaccess.ctl
Check if extended permissions are disabled.
If extended permissions are not disabled, this is a finding.
Fix
Remove the extended ACL from the /etc/ftpaccess.ctl file.#acledit /etc/ftpaccess.ctl
Disable extended permissions.
V-72771
Added
Findings ID: | GEN007841 | Rule ID: | SV-87413r1_rule | Severity: | medium | CCI: | CCI-001443 |
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Discussion
The use of wireless networking can introduce many different attack vectors into the organization’s network. Common attack vectors such as malicious association and ad hoc networks will allow an attacker to spoof a wireless access point (AP), allowing validated systems to connect to the malicious AP and enabling the attacker to monitor and record network traffic. These malicious APs can also serve to create a man-in-the-middle attack or be used to create a denial of service to valid network resources.Checks
This is N/A for systems that do not have wireless network adapters. Verify that there are no wireless interfaces configured on the system: # ifconfig -a eth0 Link encap:Ethernet HWaddr b8:ac:6f:65:31:e5 inet addr:192.168.2.100 Bcast:192.168.2.255 Mask:255.255.255.0 inet6 addr: fe80::baac:6fff:fe65:31e5/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:2697529 errors:0 dropped:0 overruns:0 frame:0 TX packets:2630541 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:2159382827 (2.0 GiB) TX bytes:1389552776 (1.2 GiB) Interrupt:17 lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:2849 errors:0 dropped:0 overruns:0 frame:0 TX packets:2849 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:2778290 (2.6 MiB) TX bytes:2778290 (2.6 MiB) If a wireless interface is configured, it must be documented and approved by the local Authorizing Official. If a wireless interface is configured and has not been documented and approved, this is a finding.Fix
Configure the system to disable all wireless network interfaces.
V-850
Removed
Findings ID: | GEN005160 | Rule ID: | SV-850r2_rule | Severity: | medium | CCI: | CCI-000297 |
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Discussion
.Xauthority files ensure the user is authorized to access the specific X Windows host. If .Xauthority files are not used, it may be possible to obtain unauthorized access to the X Windows host.System AdministratorECCD-1, ECCD-2Checks
Check for .Xauthority files being utilized by looking for such files in the home directory of a user that uses X. Procedure: # cd ~someuser # ls -la .Xauthority If the .Xauthority file does not exist, ask the SA if the user is using X Windows. If the user is utilizing X Windows and the .Xauthority file does not exist, this is a finding.Fix
Ensure the X Windows host is configured to write .Xauthority files into user home directories. Edit the Xaccess file. Ensure the line that writes the .Xauthority file is uncommented.
V-904
Removed
Findings ID: | GEN001860 | Rule ID: | SV-904r3_rule | Severity: | medium | CCI: | CCI-000225 |
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Discussion
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 AdministratorChecks
NOTE: The following commands must be run in the BASH shell. Check the ownership of local initialization files. Procedure (using a shell that supports ~USER as USER's home directory): # cut -d : -f 1 /etc/passwd | xargs -n1 -IUSER sh -c "ls -l ~USER/.[a-z]*" # cut -d : -f 1 /etc/passwd | xargs -n1 -IUSER find ~USER/.dt ! -fstype nfs ! -user USER -exec ls -ld {} \; If local initialization files are not owned by the home directory's user, this is a finding.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 file names 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.
V-935
Removed
Findings ID: | GEN005880 | Rule ID: | SV-935r2_rule | Severity: | medium | CCI: | CCI-000225 |
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Discussion
If the NFS server allows root access to local file systems from remote hosts, this access could be used to compromise the system.System AdministratorInformation Assurance OfficerInformation Assurance ManagerEBRP-1Checks
Determine if the NFS server is exporting with the root access option. Procedure: # exportfs -v | grep "root=" If an export with the root option is found, this is a finding.Fix
Edit /etc/exports and remove the root= option for all exports. Re-export the file systems.
V-941
Removed
Findings ID: | GEN006600 | Rule ID: | SV-941r2_rule | Severity: | medium | CCI: | CCI-000126 |
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Discussion
If access attempts are not logged, then multiple attempts to log on to the system by an unauthorized user may go undetected.System AdministratorECAR-2, ECAR-3Checks
Normally, TCPD logs to the mail facility in /etc/syslog.conf. Determine if syslog is configured to log events by TCPD. Procedure: # more /etc/syslog.conf Look for entries similar to the following: mail.debug /var/adm/maillog mail.none /var/adm/maillog mail.* /var/log/mail auth.info /var/log/messages The above entries would indicate mail alerts are being logged. If no entries for mail exist, then TCPD is not logging and this is a finding.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 logged into the system log files. If an alternate application is used, it must support this function.
V-22541
Removed
Findings ID: | GEN007700 | Rule ID: | SV-38918r1_rule | Severity: | medium | CCI: | CCI-001551 |
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Discussion
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-1Checks
AIX comes with IPv6 protocol handler installed and active. The only configured IPv6 address is the loopback localhost adapter. Check if any other interfaces have IPv6 addresses active. # ifconfig -a If any IPv6 addresses are configured on any network interfaces other than loopback and IPv6 is not needed, this is a finding.Fix
Unbind the IPv6 protocol handler from the network stack. Edit /etc/rc.tcpip and comment out autoconf6 to prevent IPv6 from auto starting. Unconfigure IPv6 addresses from interfaces not used with smit. #smit chinet6
V-22542
Removed
Findings ID: | GEN007720 | Rule ID: | SV-38922r1_rule | Severity: | medium | CCI: | CCI-001551 |
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