Invoke-Obfuscation Via Stdin - Security — Sigma Rule

Rule metadata and linked tags

Author: Nikita Nazarov, oscd.community. Source status: test; severity: high. Source dates: 2020-10-12 / 2022-11-29.

{
  "product": "windows",
  "service": "security",
  "definition": "The 'System Security Extension' audit subcategory need to be enabled to log the EID 4697"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: c1e94e35a0107561ac6b9fab45a028b5c393fe20fcd70b8442cf3545d20ac187

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: Invoke-Obfuscation Via Stdin - Security
id: 80b708f3-d034-40e4-a6c8-d23b7a7db3d1
related:
    - id: 487c7524-f892-4054-b263-8a0ace63fc25
      type: derived
status: test
description: Detects Obfuscated Powershell via Stdin in Scripts
references:
    - https://github.com/SigmaHQ/sigma/issues/1009 # (Task28)
author: Nikita Nazarov, oscd.community
date: 2020-10-12
modified: 2022-11-29
tags:
    - attack.stealth
    - attack.t1027
    - attack.execution
    - attack.t1059.001
logsource:
    product: windows
    service: security
    definition: The 'System Security Extension' audit subcategory need to be enabled to log the EID 4697
detection:
    selection:
        EventID: 4697
        ServiceFileName|contains|all:
            - 'set'
            - '&&'
        ServiceFileName|contains:
            - 'environment'
            - 'invoke'
            - '${input)'
    condition: selection
falsepositives:
    - Unknown
level: high

Original YAML and metadata in JSON

False positives

• Unknown

Source references

• https://github.com/SigmaHQ/sigma/issues/1009