STIGQter: STIG Summary: Anduril NixOS Security Technical Implementation Guide Version: 1 Release: 2 Benchmark Date: 01 Oct 2025:

NixOS must not allow direct login to the root account via SSH.

DISA Rule

SV-268137r1131078_rule

Vulnerability Number

V-268137

Group Title

SRG-OS-000109-GPOS-00056

Rule Version

ANIX-00-000890

Severity

CAT II

CCI(s)

• CCI-004045 - Require users to be individually authenticated before granting access to the shared accounts or resources.

Weight

10

Fix Recommendation

Configure NixOS to ensure the root user login via SSH is disabled.

Add the following Nix code to the NixOS Configuration, usually located in /etc/nixos/configuration.nix or /etc/nixos/flake.nix:

services.openssh.permitRootLogin = "no";

Rebuild and switch to the new NixOS configuration:
$ sudo nixos-rebuild switch

Check Contents

Verify the NixOS configuration disallows directly logging into the root account via SSH with the following command:

$ grep PermitRootLogin /etc/ssh/sshd_config

PermitRootLogin no

If the value is anything other than "no", this is a finding.

Vulnerability Number

V-268137

Documentable

False

Rule Version

ANIX-00-000890

Severity Override Guidance

Verify the NixOS configuration disallows directly logging into the root account via SSH with the following command:

$ grep PermitRootLogin /etc/ssh/sshd_config

PermitRootLogin no

If the value is anything other than "no", this is a finding.

Check Content Reference

M

Target Key

5658