Title

NixOS must require the change of at least 50 percent of the total number of characters when passwords are changed. (Cat II impact)

Discussion

Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks.

Check Content

Verify NixOS enforces password complexity by requiring that at least 50 percent of the characters are changed with the following command: $ grep difok /etc/security/pwquality.conf difok=8 If the value of "difok" is set to less than "8", or is commented out, this is a finding.

Fix Text

Configure NixOS to enforce password complexity. Add/modify /etc/nixos/configuration.nix to include the following lines: environment.etc."/security/pwquality.conf".text = '' difok=8 ''; Rebuild the system with the following command: $ sudo nixos-rebuild switch

Additional Identifiers

Rule ID: SV-268129r1039275_rule

Vulnerability ID: V-268129

Group Title: SRG-OS-000072-GPOS-00040

Expert Comments

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