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If cached authentication information is out-of-date, the validity of the authentication information may be questionable.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 NixOS to prohibit the use of cached credentials older than one day. Add the following Nix code to the NixOS Configuration, usually located in /etc/nixos/configuration.nix or /etc/nixos/flake.nix: Note: The entire sssd.conf must be entered in this option. services.sssd.config = '' ... [pam] offline_credentials_expiration = 1 ... ''; Rebuild and switch to the new NixOS configuration: $ sudo nixos-rebuild switch

Additional Identifiers

Rule ID: SV-268178r1131164_rule

Vulnerability ID: V-268178

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

Expert Comments

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