Ubuntu 22.04

Ubuntu 22.04 LTS must be configured such that Pluggable Authentication Module (PAM) prohibits the use of cached authentications after one day

STIG ID: UBTU-22-631015 | SRG: SRG-OS-000383-GPOS-00166 | Severity: Low | CCI: CCI-002007 | Vulnerability ID: V-260581

Description

If cached authentication information is out-of-date, the validity of the authentication information may be questionable.

Check

C-64310r953554_chk

Verify that PAM prohibits the use of cached authentications after one day by using the following command: Note: If smart card authentication is not being used on the system, this requirement is not applicable. $ sudo grep -i '^\s*offline_credentials_expiration' /etc/sssd/sssd.conf /etc/sssd/conf.d/*.conf /etc/sssd/sssd.conf:offline_credentials_expiration = 1 If "offline_credentials_expiration" is not set to "1", is commented out, is missing, or conflicting results are returned, this is a finding.

Fix

F-64218r953555_fix

Configure PAM to prohibit the use of cached authentications after one day. Add or modify the following line in the "/etc/sssd/sssd.conf" file, just below the line "[pam]": offline_credentials_expiration = 1 Note: It is valid for this configuration to be in a file with a name that ends with ".conf" and does not begin with a "." in the "/etc/sssd/conf.d/" directory instead of the "/etc/sssd/sssd.conf" file.