PowerShell Decompress Commands — Sigma Rule

Rule metadata and linked tags

Author: Roberto Rodriguez (Cyb3rWard0g), OTR (Open Threat Research). Source status: test; severity: informational. Source dates: 2020-05-02 / 2022-12-25.

{
  "product": "windows",
  "category": "ps_module",
  "definition": "0ad03ef1-f21b-4a79-8ce8-e6900c54b65b"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: b2728904de0dd6798342e85e72161b1e3286d5e19866ba3ddea4f9d5c2fa371c

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: PowerShell Decompress Commands
id: 1ddc1472-8e52-4f7d-9f11-eab14fc171f5
related:
    - id: 81fbdce6-ee49-485a-908d-1a728c5dcb09
      type: derived
status: test
description: A General detection for specific decompress commands in PowerShell logs. This could be an adversary decompressing files.
references:
    - https://github.com/OTRF/detection-hackathon-apt29/issues/8
    - https://github.com/OTRF/ThreatHunter-Playbook/blob/2d4257f630f4c9770f78d0c1df059f891ffc3fec/docs/evals/apt29/detections/4.A.3_09F29912-8E93-461E-9E89-3F06F6763383.md
author: Roberto Rodriguez (Cyb3rWard0g), OTR (Open Threat Research)
date: 2020-05-02
modified: 2022-12-25
tags:
    - attack.stealth
    - attack.t1140
logsource:
    product: windows
    category: ps_module
    definition: 0ad03ef1-f21b-4a79-8ce8-e6900c54b65b
detection:
    selection_4103:
        Payload|contains: 'Expand-Archive'
    condition: selection_4103
falsepositives:
    - Unknown
level: informational

Original YAML and metadata in JSON

False positives

• Unknown

Source references

• https://github.com/OTRF/detection-hackathon-apt29/issues/8
• https://github.com/OTRF/ThreatHunter-Playbook/blob/2d4257f630f4c9770f78d0c1df059f891ffc3fec/docs/evals/apt29/detections/4.A.3_09F29912-8E93-461E-9E89-3F06F6763383.md