Gatekeeper Bypass via Xattr — Sigma Rule

Rule metadata and linked tags

Author: Daniil Yugoslavskiy, oscd.community. Source status: test; severity: low. Source dates: 2020-10-19 / 2024-04-18.

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

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: d23c6b4a3a3271d993bb851049f35c7946408445a9dcf914367856cd8ea6cd9c

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: Gatekeeper Bypass via Xattr
id: f5141b6d-9f42-41c6-a7bf-2a780678b29b
status: test
description: Detects macOS Gatekeeper bypass via xattr utility
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/1fed40dc7e48f16ed44dcdd9c73b9222a70cca85/atomics/T1553.001/T1553.001.md
    - https://www.loobins.io/binaries/xattr/
author: Daniil Yugoslavskiy, oscd.community
date: 2020-10-19
modified: 2024-04-18
tags:
    - attack.defense-impairment
    - attack.t1553.001
logsource:
    category: process_creation
    product: macos
detection:
    selection:
        Image|endswith: '/xattr'
        CommandLine|contains|all:
            - '-d'
            - 'com.apple.quarantine'
    condition: selection
falsepositives:
    - Legitimate activities
level: low

Original YAML and metadata in JSON

False positives

• Legitimate activities

Source references

• https://github.com/redcanaryco/atomic-red-team/blob/1fed40dc7e48f16ed44dcdd9c73b9222a70cca85/atomics/T1553.001/T1553.001.md
• https://www.loobins.io/binaries/xattr/