Title

NixOS must generate audit records when successful/unsuccessful attempts to delete privileges occur. (Cat II impact)

Discussion

Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an incident or identify those responsible for one. Audit records can be generated from various components within the information system (e.g., module or policy filter).

Check Content

Verify NixOS generates audit records when attempts to delete privileges occur with the following command: $ sudo auditctl -l | grep usermod -a always,exit -S all -F path=/run/current-system/sw/bin/usermod -F perm=x -F auid>=1000 -F auid!=-1 -k privileged-usermod If the command does not return an audit rule for "usermod", this is a finding.

Fix Text

Configure NixOS to record attempts to delete privileges. Add the following Nix code to the NixOS Configuration, usually located in /etc/nixos/configuration.nix or /etc/nixos/flake.nix: security.audit.rules = [ "-a always,exit -F path=/run/current-system/sw/bin/usermod -F perm=x -F auid>=1000 -F auid!=unset -k privileged-usermod" ]; Rebuild and switch to the new NixOS configuration: $ sudo nixos-rebuild switch

Additional Identifiers

Rule ID: SV-268164r1131133_rule

Vulnerability ID: V-268164

Group Title: SRG-OS-000466-GPOS-00210

Expert Comments

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