DBN-6300 NDM Security Technical Implementation Guide

Upon gaining access to a network device, an attacker will often first attempt to create a persistent method of reestablishing access. One way to accomplish this is to create a new account. This control does not apply to the account of last resort or root account. DoD prohibits local user accounts on the device, except for an account of last resort and (where applicable) a root account. With the DB-6300, audit records are automatically backed up on a real-time basis via syslog when enabled.

Upon gaining access to a network device, an attacker will often attempt to create a persistent method of reestablishing access. One way to accomplish this is to modify an account. This control does not apply to the account of last resort or root account. DoD prohibits local user accounts on the device, except for an account of last resort and (where applicable) a root account. Account management functions include assignment of group or role membership; identifying account type; specifying user access authorizations (i.e., privileges); account removal, update, or termination; and administrative alerts. With the DBN-6300, audit records are automatically backed up on a real-time basis via syslog when enabled.

Protecting access authorization information (i.e., access control decisions) ensures that authorization information cannot be altered, spoofed, or otherwise compromised during transmission. In distributed information systems, authorization processes and access control decisions may occur in separate parts of the systems. In such instances, authorization information is transmitted securely so timely access control decisions can be enforced at the appropriate locations. To support the access control decisions, it may be necessary to transmit, as part of the access authorization information, supporting security attributes. This is because, in distributed information systems, there are various access control decisions that need to be made, and different entities (e.g., services) make these decisions in a serial fashion, each requiring some security attributes to make the decisions.

Account management, as a whole, ensures access to the network device is being controlled in a secure manner by granting access to only authorized personnel. Auditing account removal actions will support account management procedures. When device management accounts are terminated, user or service accessibility may be affected. Auditing also ensures authorized active accounts remain enabled and available for use when required. With the DBN-6300, audit records are automatically backed up on a real-time basis via syslog when enabled.

By limiting the number of failed logon attempts, the risk of unauthorized system access via user password guessing, otherwise known as brute-forcing, is reduced. It is possible to set a time-to-retry variable, as well as number of retries during that lockout timeout variable, within the DBN-6300.

Auditing and logging are key components of any security architecture. Logging the actions of specific events provides a means to investigate an attack; to recognize resource utilization or capacity thresholds; or to identify an improperly configured network device. If auditing is not comprehensive, it will not be useful for intrusion monitoring, security investigations, and forensic analysis. With the DBN-6300, audit records are automatically backed up on a real-time basis via syslog when enabled.

Without the capability to generate audit records, it would be difficult to establish, correlate, and investigate the events relating to an incident or identify those responsible for one. Audit records can be generated from various components within the network device (e.g., process, module). Certain specific device functionalities may be audited as well. The list of audited events is the set of events for which audits are to be generated. This set of events is typically a subset of the list of all events for which the system is capable of generating audit records. DoD has defined the list of events for which the device will provide an audit record generation capability as the following: (i) Successful and unsuccessful attempts to access, modify, or delete privileges, security objects, security levels, or categories of information (e.g., classification levels); (ii) Access actions, such as successful and unsuccessful logon attempts, privileged activities or other system level access, starting and ending time for user access to the system, concurrent logons from different workstations, successful and unsuccessful accesses to objects, all program initiations, and all direct access to the information system; and (iii) All account creation, modification, disabling, and termination actions. With the DB-6300, audit records are automatically backed up on a real-time basis via syslog when enabled.

Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an incident or identify those responsible for one. Audit records can be generated from various components within the information system (e.g., module or policy filter). It is not possible to perform unsuccessful commands in the UI web management interface since it is a GUI interface. Unauthorized menu items/commands are not visible.

In order to determine what is happening within the network infrastructure or to resolve and trace an attack, the network device must support the organization's capability to correlate the audit log data from multiple network devices to acquire a clear understanding of events. In order to correlate auditable events, time stamps are needed on all of the log records. If the internal clock is not used, the system may not be able to provide time stamps for log messages. Additionally, externally generated time stamps may not be accurate. Applications can use the capability of an operating system or purpose-built module for this purpose. (Note that the internal clock is required to be synchronized with authoritative time sources by other requirements.)

Multifactor authentication requires using two or more factors to achieve authentication. Factors include: (i) something a user knows (e.g., password/PIN); (ii) something a user has (e.g., cryptographic identification device, token); or (iii) something a user is (e.g., biometric). Network access is defined as access to an information system by a user (or a process acting on behalf of a user) communicating through a network (e.g., LAN, WAN, or the Internet). DoD has mandated the use of the Common Access Card (CAC) token/credential to support identity management and personal authentication for systems covered under HSPD 12. DoD recommended architecture for network devices is for system administrators to authenticate using an authentication server using the DoD CAC credential with DoD-approved PKI. This requirement also applies to the account of last resort and the root account only if non-local access via the network is enabled for these accounts (not recommended). This control does not apply to the account of last resort or root account. DoD prohibits local user accounts on the device, except for an account of last resort and (where applicable) a root account.

Multifactor authentication is defined as using two or more factors to achieve authentication. Factors include: (i) Something a user knows (e.g., password/PIN); (ii) Something a user has (e.g., cryptographic identification device, token); or (iii) Something a user is (e.g., biometric). To ensure accountability and prevent unauthenticated access, privileged users must utilize multifactor authentication to prevent potential misuse and compromise of the system. Local access is defined as access to an organizational information system by a user (or process acting on behalf of a user) communicating through a direct connection without the use of a network. Applications integrating with the DoD Active Directory and utilizing the DoD CAC are examples of compliant multifactor authentication solutions. This control does not apply to the account of last resort or root account. DoD prohibits local user accounts on the device, except for an account of last resort and (where applicable) a root account.

A replay attack may enable an unauthorized user to gain access to the application. Authentication sessions between the authenticator and the application validating the user credentials must not be vulnerable to a replay attack. An authentication process resists replay attacks if it is impractical to achieve a successful authentication by recording and replaying a previous authentication message. Techniques used to address this include protocols using nonces (e.g., numbers generated for a specific one-time use) or challenges (e.g., TLS, WS_Security). Additional techniques include time-synchronous or challenge-response one-time authenticators.

Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks. Password length is one factor of several that helps to determine strength and how long it takes to crack a password. Since the device cannot be configured for password complexity, not having a strong password can result in the success of a brute force attack, which would give immediate access to a privileged system.

Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks. To meet password policy requirements, passwords need to be changed at specific policy-based intervals. If the network device allows the user to consecutively reuse their password when that password has exceeded its defined lifetime, the end result is a password that is not changed as per policy requirements.

Use of a complex passwords helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks. Password complexity is one factor of several that determine how long it takes to crack a password. The more complex the password is, the greater the number of possible combinations that need to be tested before the password is compromised.

Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks. Password complexity is one factor of several that determine how long it takes to crack a password. The more complex the password, the greater the number of possible combinations that need to be tested before the password is compromised.

Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks. Password complexity is one factor of several that determine how long it takes to crack a password. The more complex the password, the greater the number of possible combinations that need to be tested before the password is compromised.

Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks. Password complexity is one factor of several that determine how long it takes to crack a password. The more complex the password, the greater the number of possible combinations that need to be tested before the password is compromised.

Enforcing a minimum password lifetime helps prevent repeated password changes to defeat the password reuse or history enforcement requirement. Restricting this setting limits the user's ability to change their password. Passwords need to be changed at specific policy-based intervals; however, if the network device allows the user to immediately and continually change their password, then the password could be repeatedly changed in a short period of time to defeat the organization's policy regarding password reuse.

Any password, no matter how complex, can eventually be cracked. Therefore, passwords need to be changed at specific intervals. One method of minimizing this risk is to use complex passwords and periodically change them. If the network device does not limit the lifetime of passwords and force users to change their passwords, there is the risk that the passwords could be compromised. This requirement does not include emergency administration accounts which are meant for access to the network device in case of failure. These accounts are not required to have maximum password lifetime restrictions.

Only authorized personnel should be aware of errors and the details of the errors. Error messages are an indicator of an organization's operational state. Additionally, sensitive account information must not be revealed through error messages to unauthorized personnel or their designated representatives. The DBN-6300 will reveal error messages only to authorized individuals (ISSO, ISSM, and SA). Only privileged users have visibility into any error messages. The audit log requires authorized users to log on to obtain visibility. With the DBN-6300, audit records are automatically backed up on a real-time basis via syslog when enabled.

Predictable failure prevention requires organizational planning to address device failure issues. If components key to maintaining the device's security fail to function, the device could continue operating in a nonsecure state. If appropriate actions are not taken when a network device failure occurs, a denial-of-service condition may occur that could result in mission failure because the network would be operating without a critical security monitoring and prevention function. Upon detecting a failure of network device security components, the network device must activate a system alert message, send an alarm, or shut down. With the DBN-6300, audit records are automatically backed up on a real-time basis via syslog when enabled.

Automatic session termination addresses the termination of administrator-initiated logical sessions in contrast to the termination of network connections that are associated with communications sessions (i.e., network disconnect). A logical session (for local, network, and remote access) is initiated whenever an administrator (or process acting on behalf of a user) accesses a network device. Such administrator sessions can be terminated (and thus terminate network administrator access) without terminating network sessions. Session termination terminates all processes associated with an administrator's logical session except those processes that are specifically created by the administrator (i.e., session owner) to continue after the session is terminated. Conditions or trigger events requiring automatic session termination can include, for example, organization-defined periods of user inactivity, targeted responses to certain types of incidents, and time-of-day restrictions on information system use. These conditions will vary across environments and network device types.

Once an attacker establishes initial access to a system, the attacker often attempts to create a persistent method of reestablishing access. One way to accomplish this is for the attacker to simply enable a new or disabled account. Notification of account enabling is one method for mitigating this risk. A comprehensive account management process will ensure an audit trail that documents the creation of application user accounts and notifies administrators and ISSOs. Such a process greatly reduces the risk that accounts will be surreptitiously created and provides logging that can be used for forensic purposes. With the DBN-6300, audit records are automatically backed up on a real-time basis via syslog when enabled.

Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised information system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider threats and the advanced persistent threat. With the DBN-6300, audit records are automatically backed up on a real-time basis via syslog when enabled.

Inaccurate time stamps make it more difficult to correlate events and can lead to an inaccurate analysis. Determining the correct time a particular event occurred on a system is critical when conducting forensic analysis and investigating system events. Sources outside of the configured acceptable allowance (drift) may be inaccurate. Additionally, unnecessary synchronization may have an adverse impact on system performance and may indicate malicious activity. Synchronizing internal information system clocks provides uniformity of time stamps for information systems with multiple system clocks and systems connected over a network.

Inaccurate time stamps make it more difficult to correlate events and can lead to an inaccurate analysis. Determining the correct time a particular event occurred on a system is critical when conducting forensic analysis and investigating system events. Synchronizing internal information system clocks provides uniformity of time stamps for information systems with multiple system clocks and systems connected over a network. Organizations should consider setting time periods for different types of systems (e.g., financial, legal, or mission-critical systems). Organizations should also consider endpoints that may not have regular access to the authoritative time server (e.g., mobile, teleworking, and tactical endpoints). This requirement is related to the comparison done every 24 hours in CCI-001891 because a comparison must be done in order to determine the time difference. The organization-defined time period will depend on multiple factors, most notably the granularity of time stamps in audit logs. For example, if time stamps only show to the nearest second, there is no need to have accuracy of a tenth of a second in clocks.

If time stamps are not consistently applied and there is no common time reference, it is difficult to perform forensic analysis.

Without sufficient granularity of time stamps, it is not possible to adequately determine the chronological order of records. Time stamps generated by the application include date and time. Granularity of time measurements refers to the degree of synchronization between information system clocks and reference clocks.

Without auditing the enforcement of access restrictions against changes to the device configuration, it will be difficult to identify attempted attacks, and an audit trail will not be available for forensic investigation for after-the-fact actions. Enforcement actions are the methods or mechanisms used to prevent unauthorized changes to configuration settings. Enforcement action methods may be as simple as denying access to a file based on the application of file permissions (access restriction). Audit items may consist of lists of actions blocked by access restrictions or changes identified after the fact. With the DBN-6300, audit records are automatically backed up on a real-time basis via syslog when enabled.

This requires the use of secure protocols instead of their unsecured counterparts, such as SSH instead of telnet, SCP instead of FTP, and HTTPS instead of HTTP. If unsecured protocols (lacking cryptographic mechanisms) are used for sessions, the contents of those sessions will be susceptible to manipulation, potentially allowing alteration and hijacking of maintenance sessions.

This requires the use of secure protocols instead of their unsecured counterparts, such as SSH instead of telnet, SCP instead of FTP, and HTTPS instead of HTTP. If unsecured protocols (lacking cryptographic mechanisms) are used for sessions, the contents of those sessions will be susceptible to eavesdropping, potentially putting sensitive data (including administrator passwords) at risk of compromise and potentially allowing hijacking of maintenance sessions.

Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an incident or identify those responsible for one. Audit records can be generated from various components within the network device (e.g., module or policy filter). Administrative roles cannot be changed on the device console; thus, this only applies to the User Interface (UI) web management tool. All account activities (creation, modification, disabling, and removal, and other account activities, including successful/unsuccessful attempts to modify administrator privileges) on the DBN-6300 are written out to an audit log. This log carries a wealth of information that provides valuable forensic help, including the origin IP and port and destination and port where the event occurred, as well as the type of event and when it occurred. This data is all used to help establish the identity of any individual or process associated with the event. This can be verified by accessing the audit logs remotely by downloading the System State Report. With the DBN-6300, audit records are automatically backed up on a real-time basis via syslog when enabled.

Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an incident or identify those responsible for one. Audit records can be generated from various components within the network device (e.g., module or policy filter). With the DBN-6300, audit records are automatically backed up on a real-time basis via syslog when enabled.

Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an incident or identify those responsible for one. Audit records can be generated from various components within the network device (e.g., module or policy filter). With the DBN-6300 Audit records are automatically backed up on a real-time basis via syslog when enabled.

Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an incident or identify those responsible for one. Audit records can be generated from various components within the network device (e.g., module or policy filter). With the DBN-6300, audit records are automatically backed up on a real-time basis via syslog when enabled.

Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an incident or identify those responsible for one. Audit records can be generated from various components within the network device (e.g., module or policy filter). With the DBN-6300, audit records are automatically backed up on a real-time basis via syslog when enabled.

Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an incident or identify those responsible for one. Audit records can be generated from various components within the network device (e.g., module or policy filter). With the DBN-6300, audit records are automatically backed up on a real-time basis via syslog when enabled.

Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an incident or identify those responsible for one. Audit records can be generated from various components within the network device (e.g., module or policy filter). With the DBN-6300, audit records are automatically backed up on a real-time basis via syslog when enabled.

Off-loading ensures audit information does not get overwritten if the limited audit storage capacity is reached and also protects the audit record in case the system/component being audited is compromised. The intent of this control is to ensure that log information does not get overwritten if the limited log storage capacity is reached and also to protect the log records in general if the system/component being logged is compromised (hence the notion of off-loading onto a different system or media) but the intent is not to hold the information in more than one or multiple locations. This requirement is intended to address the primary repository, which is on the centralized Syslog server. This requirement is only applicable to the server used as the Syslog server. With the DBN-6300, audit records are automatically backed up on a real-time basis via syslog when enabled.

Centralized management of authentication settings increases the security of remote and nonlocal access methods. This control is particularly important protection against the insider threat. With robust centralized management, audit records for administrator account access to the organization's network devices can be more readily analyzed for trends and anomalies. The alternative method of defining administrator accounts on each device exposes the device configuration to remote access authentication attacks and system administrators with multiple authenticators for each network device.

For user certificates, each organization obtains certificates from an approved, shared service provider, as required by OMB policy. For federal agencies operating a legacy public key infrastructure cross-certified with the Federal Bridge Certification Authority at medium assurance or higher, this Certification Authority will suffice. Self-signed certificates are not allowed.