Title

NixOS must prohibit the use of cached authenticators after one day. (Cat II impact)

Discussion

If cached authentication information is out-of-date, the validity of the authentication information may be questionable.

Check Content

Verify NixOS, for PKI-based authentication, only caches authenticators for one day with the following command: $ sudo grep expiration /etc/sssd/sssd.conf offline_credentials_expiration = 1 If the offline_credentials_expiration is not set to "1" or is commented out, this is a finding.

Fix Text

Configure /etc/nixos/configuration.nix to prohibit the use of cached credentials older than one day by adding the following configuration settings. Note that the entire sssd.conf must be entered in this option: services.sssd.config = '' ... [pam] offline_credentials_expiration = 1 ... ''; Rebuild the system with the following command: $ sudo nixos-rebuild switch

Additional Identifiers

Rule ID: SV-268178r1039543_rule

Vulnerability ID: V-268178

Group Title: SRG-OS-000383-GPOS-00166

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.