Time Machine Backup Disabled Via Tmutil - MacOS — Sigma Rule

Rule metadata and linked tags

Author: Pratinav Chandra. Source status: test; severity: medium. Source dates: 2024-05-29 / not supplied.

{
  "category": "process_creation",
  "product": "macos"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 47aeb8c74ea31a5698a8b084915c49d7e9edc89b317a407bc1d6e10eaf4c548d

Detection logic

Original source YAML. Source-tag agreement is not proof of complete semantic coverage. This rule has not been compiled for a SIEM backend or validated against live telemetry here.

title: Time Machine Backup Disabled Via Tmutil - MacOS
id: 2c95fa8a-8b8d-4787-afce-7117ceb8e3da
status: test
description: |
    Detects disabling of Time Machine (Apple's automated backup utility software) via the native macOS backup utility "tmutil".
    An attacker can use this to prevent backups from occurring.
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/master/atomics/T1490/T1490.md#atomic-test-12---disable-time-machine
    - https://www.loobins.io/binaries/tmutil/
author: Pratinav Chandra
date: 2024-05-29
tags:
    - attack.impact
    - attack.t1490
logsource:
    category: process_creation
    product: macos
detection:
    selection_img:
        - Image|endswith: '/tmutil'
        - CommandLine|contains: 'tmutil'
    selection_cmd:
        CommandLine|contains: 'disable'
    condition: all of selection_*
falsepositives:
    - Legitimate administrator activity
level: medium

Original YAML and metadata in JSON

False positives

• Legitimate administrator activity

Source references

• https://github.com/redcanaryco/atomic-red-team/blob/master/atomics/T1490/T1490.md#atomic-test-12---disable-time-machine
• https://www.loobins.io/binaries/tmutil/