Invoke-Obfuscation Via Use Rundll32 - PowerShell Module — Sigma Rule

Rule metadata and linked tags

Author: Nikita Nazarov, oscd.community. Source status: test; severity: high. Source dates: 2019-10-08 / 2022-11-29.

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

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: f55c2b4818959afca82a6550fd4d633d061db43a17080e822bea9cc2eca567a9

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 Use Rundll32 - PowerShell Module
id: 88a22f69-62f9-4b8a-aa00-6b0212f2f05a
related:
    - id: a5a30a6e-75ca-4233-8b8c-42e0f2037d3b
      type: derived
status: test
description: Detects Obfuscated Powershell via use Rundll32 in Scripts
references:
    - https://github.com/SigmaHQ/sigma/issues/1009
author: Nikita Nazarov, oscd.community
date: 2019-10-08
modified: 2022-11-29
tags:
    - attack.stealth
    - attack.t1027
    - attack.execution
    - attack.t1059.001
logsource:
    product: windows
    category: ps_module
    definition: 0ad03ef1-f21b-4a79-8ce8-e6900c54b65b
detection:
    selection_4103:
        Payload|contains|all:
            - '&&'
            - 'rundll32'
            - 'shell32.dll'
            - 'shellexec_rundll'
        Payload|contains:
            - 'value'
            - 'invoke'
            - 'comspec'
            - 'iex'
    condition: selection_4103
falsepositives:
    - Unknown
level: high

Original YAML and metadata in JSON

False positives

• Unknown

Source references

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