Title

NixOS must remove all software components after updated versions have been installed. (Cat II impact)

Discussion

Previous versions of software components that are not removed from the information system after updates have been installed may be exploited by adversaries. Some information technology products may remove older versions of software automatically from the information system.

Check Content

Verify NixOS removes all software components after updated versions have been installed by reviewing /etc/nixos/configuration.nix and remove any references to outdated versions of nixpkgs. If any outdated versions of nixpkgs are present in the configuration.nix file, this is a finding.

Fix Text

After updating NixOS (either via "cd /etc/nixos; sudo nix flake update; sudo nixos-rebuild switch" or "sudo nixos-rebuild switch –upgrade"), reboot the system to ensure all running software comes from the current active NixOS generation. Edit /etc/nixos/configuration.nix and remove any references to outdated versions of nixpkgs.

Additional Identifiers

Rule ID: SV-268162r1039374_rule

Vulnerability ID: V-268162

Group Title: SRG-OS-000437-GPOS-00194

Expert Comments

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