Scheduled Cron Task/Job - MacOs — Sigma Rule

Rule metadata and linked tags

Author: Alejandro Ortuno, oscd.community. Source status: test; severity: medium. Source dates: 2020-10-06 / 2022-11-27.

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

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: c3d5daf4e7a73760aa67850eeaf96f497ec394a5dad2b9282df86a0bd7d932fb

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: Scheduled Cron Task/Job - MacOs
id: 7c3b43d8-d794-47d2-800a-d277715aa460
status: test
description: Detects abuse of the cron utility to perform task scheduling for initial or recurring execution of malicious code. Detection will focus on crontab jobs uploaded from the tmp folder.
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1053.003/T1053.003.md
author: Alejandro Ortuno, oscd.community
date: 2020-10-06
modified: 2022-11-27
tags:
    - attack.execution
    - attack.persistence
    - attack.privilege-escalation
    - attack.t1053.003
logsource:
    category: process_creation
    product: macos
detection:
    selection:
        Image|endswith: '/crontab'
        CommandLine|contains: '/tmp/'
    condition: selection
falsepositives:
    - Legitimate administration activities
level: medium

Original YAML and metadata in JSON

False positives

• Legitimate administration activities

Source references

• https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1053.003/T1053.003.md