Anduril NixOS STIG Version Comparison

There are 38 differences between versions v1 r1 (Oct. 22, 2024) (the "left" version) and v1 r2 (Oct. 1, 2025) (the "right" version).

Check ANIX-00-001680 was removed from the benchmark in the "right" version. The text below reflects the old wording.

This check's original form is available here.

Title

NixOS must remove all software components after updated versions have been installed.

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after updated versions have been installed by reviewing /etc/nixos/configuration.nix and remove any references to outdated versions of nixpkgs. If any outdated versions of nixpkgs are present in the configuration.nix file, this is a finding.

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.

Fix

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 Edit /etc/nixos/configuration.nix and remove any references to outdated versions of nixpkgs.