RunDLL32 Spawning Explorer — Sigma Rule

Rule metadata and linked tags

Author: elhoim, CD_ROM_. Source status: test; severity: high. Source dates: 2022-04-27 / 2022-05-25.

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

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 8d8583eb98b1881599ed60405d48a8878c16b5b362192164ef81b350929e0284

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: RunDLL32 Spawning Explorer
id: caa06de8-fdef-4c91-826a-7f9e163eef4b
status: test
description: Detects RunDLL32.exe spawning explorer.exe as child, which is very uncommon, often observes Gamarue spawning the explorer.exe process in an unusual way
references:
    - https://redcanary.com/blog/intelligence-insights-november-2021/
author: elhoim, CD_ROM_
date: 2022-04-27
modified: 2022-05-25
tags:
    - attack.stealth
    - attack.t1218.011
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        ParentImage|endswith: '\rundll32.exe'
        Image|endswith: '\explorer.exe'
    filter:
        ParentCommandLine|contains: '\shell32.dll,Control_RunDLL'
    condition: selection and not filter
falsepositives:
    - Unknown
level: high

Original YAML and metadata in JSON

False positives

• Unknown

Source references

• https://redcanary.com/blog/intelligence-insights-november-2021/