Skip to content

Canonical Ubuntu 20.04 LTS Security Technical Implementation Guide

Rules, Groups, and Values defined within the XCCDF Benchmark

  • The Ubuntu operating system must provision temporary user accounts with an expiration time of 72 hours or less.

    If temporary user accounts remain active when no longer needed or for an excessive period, these accounts may be used to gain unauthorized access. To mitigate this risk, automated termination of al...
    Rule Medium Severity
  • The Ubuntu operating system must enable the graphical user logon banner to display the Standard Mandatory DoD Notice and Consent Banner before granting local access to the system via a graphical user logon.

    Display of a standardized and approved use notification before granting access to the Ubuntu operating system ensures privacy and security notification verbiage used is consistent with applicable f...
    Rule Medium Severity
  • The Ubuntu operating system must retain a user's session lock until that user reestablishes access using established identification and authentication procedures.

    A session lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but does not want to log out because of the temporary...
    Rule Medium Severity
  • Ubuntu operating systems when booted must require authentication upon booting into single-user and maintenance modes.

    To mitigate the risk of unauthorized access to sensitive information by entities that have been issued certificates by DoD-approved PKIs, all DoD systems (e.g., web servers and web portals) must be...
    Rule High Severity
  • The Ubuntu operating system must automatically terminate a user session after inactivity timeouts have expired.

    Automatic session termination addresses the termination of user-initiated logical sessions in contrast to the termination of network connections that are associated with communications sessions (i....
    Rule Medium Severity
  • The Ubuntu operating system must implement smart card logins for multifactor authentication for local and network access to privileged and nonprivileged accounts.

    Without the use of multifactor authentication, the ease of access to privileged functions is greatly increased. Multifactor authentication requires using two or more factors to achieve authentica...
    Rule Medium Severity
  • The Ubuntu operating system must immediately terminate all network connections associated with SSH traffic after a period of inactivity.

    Automatic session termination addresses the termination of user-initiated logical sessions in contrast to the termination of network connections that are associated with communications sessions (i....
    Rule Medium Severity
  • The Ubuntu operating system must immediately terminate all network connections associated with SSH traffic at the end of the session or after 10 minutes of inactivity.

    Terminating an idle session within a short time period reduces the window of opportunity for unauthorized personnel to take control of a management session enabled on the console or console port th...
    Rule Medium Severity
  • The Ubuntu operating system must configure the SSH daemon to use FIPS 140-2 approved ciphers to prevent the unauthorized disclosure of information and/or detect changes to information during transmission.

    Without cryptographic integrity protections, information can be altered by unauthorized users without detection. Remote access (e.g., RDP) is access to DOD nonpublic information systems by an aut...
    Rule Medium Severity
  • The Ubuntu operating system must be configured so that remote X connections are disabled, unless to fulfill documented and validated mission requirements.

    The security risk of using X11 forwarding is that the client's X11 display server may be exposed to attack when the SSH client requests forwarding. A System Administrator may have a stance in which...
    Rule High Severity
  • The Ubuntu operating system must enforce password complexity by requiring that at least one lower-case character be used.

    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 resistin...
    Rule Low Severity
  • The Ubuntu operating system must prevent the use of dictionary words for passwords.

    If the Ubuntu operating system allows the user to select passwords based on dictionary words, then this increases the chances of password compromise by increasing the opportunity for successful gue...
    Rule Medium Severity
  • The Ubuntu operating system must be configured so that when passwords are changed or new passwords are established, pwquality must be used.

    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 resistin...
    Rule Medium Severity
  • The Ubuntu operating system must implement multifactor authentication for remote access to privileged accounts in such a way that one of the factors is provided by a device separate from the system gaining access.

    Using an authentication device, such as a CAC or token that is separate from the information system, ensures that even if the information system is compromised, that compromise will not affect cred...
    Rule Medium Severity
  • The Ubuntu operating system for PKI-based authentication, must implement a local cache of revocation data in case of the inability to access revocation information via the network.

    Without configuring a local cache of revocation data, there is the potential to allow access to users who are no longer authorized (users with revoked certificates).
    Rule Medium Severity
  • The Ubuntu operating system must prohibit password reuse for a minimum of five generations.

    Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks. If the information system or application allows the user...
    Rule Low Severity
  • The Ubuntu operating system must be configured so that the script which runs each 30 days or less to check file integrity is the default one.

    Without verification of the security functions, security functions may not operate correctly and the failure may go unnoticed. Security function is defined as the hardware, software, and/or firmwar...
    Rule Medium Severity
  • The Ubuntu operating system must generate audit records for all account creations, modifications, disabling, and termination events that affect /etc/passwd.

    Once an attacker establishes 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 create an acco...
    Rule Medium Severity
  • The Ubuntu operating system must generate audit records for all account creations, modifications, disabling, and termination events that affect /etc/opasswd.

    Once an attacker establishes 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 create an acco...
    Rule Medium Severity
  • The Ubuntu operating system must shut down by default upon audit failure (unless availability is an overriding concern).

    It is critical that when the operating system is at risk of failing to process audit logs as required, it takes action to mitigate the failure. Audit processing failures include: software/hardware ...
    Rule Medium Severity

The content of the drawer really is up to you. It could have form fields, definition lists, text lists, labels, charts, progress bars, etc. Spacing recommendation is 24px margins. You can put tabs in here, and can also make the drawer scrollable.

Capacity
Modules