Title

NixOS must enforce a delay of at least four seconds between logon prompts following a failed logon attempt. (Cat II impact)

Discussion

Limiting the number of logon attempts over a certain time interval reduces the chances that an unauthorized user may gain access to an account.

Check Content

Verify NixOS enforces a four-second delay between logon attempts with the following command: $ grep -I delay /etc/login.defs FAIL_DELAY 4 If "FAIL_DELAY" is not set to "4" or greater, is commented out, or is missing, this is a finding.

Fix Text

Configure NixOS to enforce a four-second delay between logon attempts. Add the following Nix code to the NixOS Configuration, usually located in /etc/nixos/configuration.nix or /etc/nixos/flake.nix: security.loginDefs.settings."FAIL_DELAY" = "4"; Rebuild and switch to the new NixOS configuration: $ sudo nixos-rebuild switch

Additional Identifiers

Rule ID: SV-268171r1134782_rule

Vulnerability ID: V-268171

Group Title: SRG-OS-000480-GPOS-00226

Expert Comments

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