macOS firmwarepasswd Command-Line Manipulation

Alerts on firmwarepasswd usage on macOS indicating firmware password set, full, delete, or check actions.

FreeReviewedSigma · Medium · v2
Product
macos
Category
process_creation
Author
Austin Songer @austinsonger (SigmaHQ), DRL 1.1
Published
2021-09-30
Updated
2026-07-31
title: macOS firmwarepasswd Command-Line Manipulation
id: 02a9e3ae-a23a-4685-acba-ffe2999d945c
status: test
description: This rule flags process executions of /usr/sbin/firmwarepasswd with command-line arguments associated with password management actions such as setting, full updates, deletion, or checks. Attackers may use firmware password manipulation to alter device security controls to persist access before the operating system loads. It relies on macOS process creation telemetry, specifically the executed image path and command-line contents of firmwarepasswd.
references:
  - https://github.com/usnistgov/macos_security/blob/932a51f3e819dd3e02ebfcf3ef433cfffafbe28b/rules/os/os_firmware_password_require.yaml
  - https://www.manpagez.com/man/8/firmwarepasswd/
  - https://support.apple.com/guide/security/firmware-password-protection-sec28382c9ca/web
  - https://github.com/SigmaHQ/sigma/blob/master/rules/macos/process_creation/proc_creation_macos_susp_macos_firmware_activity.yml
author: Austin Songer @austinsonger, Huntrule Team
date: 2021-09-30
modified: 2022-10-09
tags:
  - attack.impact
logsource:
  category: process_creation
  product: macos
detection:
  selection1:
    Image: /usr/sbin/firmwarepasswd
    CommandLine|contains:
      - setpasswd
      - full
      - delete
      - check
  condition: selection1
falsepositives:
  - Legitimate administration activities
level: medium
license: DRL-1.1
related:
  - id: 7ed2c9f7-c59d-4c82-a7e2-f859aa676099
    type: derived