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

NixOS must, for networked systems, compare internal information system clocks at least every 24 hours with a server which is synchronized to one of the redundant United States Naval Observatory (USNO) time servers, or a time server designated for the appropriate DOD network (NIPRNet/SIPRNet), and/or the Global Positioning System (GPS).

DISA Rule

SV-268149r1131099_rule

Vulnerability Number

V-268149

Group Title

SRG-OS-000355-GPOS-00143

Rule Version

ANIX-00-001420

Severity

CAT II

CCI(s)

CCI-004923 - Compare the internal system clocks on an organization-defined frequency with organization-defined authoritative time source.
CCI-001890 - Record time stamps for audit records that use Coordinated Universal Time, have a fixed local time offset from Coordinated Universal Time, or that include the local time offset as part of the time stamp.
CCI-004922 - Synchronize system clocks within and between systems or system components.

Weight

Fix Recommendation

Configure NixOS to use approved timeservers.

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

networking.timeServers = [
"tick.usnogps.navy.mil"
"tock.usnogps.navy.mil"
];

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

Check Contents

Verify NixOS is configured with an approved time server with the following command:

$ timedatectl show-timesync | grep NTPServers

SystemNTPServers=tick.usnogps.navy.mil
FallbackNTPServers=tock.usnogps.navy.mil

If the output of the command does not list authorized time servers, this is a finding.

Vulnerability Number

V-268149

Documentable

False

Rule Version

ANIX-00-001420

Severity Override Guidance

Check Content Reference

Target Key

5658