Suspicious WMIC Execution Via Office Process — Sigma Rule

Rule metadata and linked tags

Author: Vadim Khrykov, Cyb3rEng. Source status: test; severity: high. Source dates: 2021-08-23 / 2023-02-14.

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

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: b154793dc16b5c76ca61ef93d5bb471dfa4cd04cb7f3d49139092e0d48c91f4f

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: Suspicious WMIC Execution Via Office Process
id: e1693bc8-7168-4eab-8718-cdcaa68a1738
related:
    - id: 438025f9-5856-4663-83f7-52f878a70a50
      type: derived
    - id: 518643ba-7d9c-4fa5-9f37-baed36059f6a
      type: obsolete
    - id: 9d1c72f5-43f0-4da5-9320-648cf2099dd0
      type: obsolete
    - id: c0e1c3d5-4381-4f18-8145-2583f06a1fe5
      type: obsolete
    - id: 04f5363a-6bca-42ff-be70-0d28bf629ead
      type: obsolete
status: test
description: Office application called wmic to proxye execution through a LOLBIN process. This is often used to break suspicious parent-child chain (Office app spawns LOLBin).
references:
    - https://thedfirreport.com/2021/03/29/sodinokibi-aka-revil-ransomware/
    - https://github.com/vadim-hunter/Detection-Ideas-Rules/blob/02bcbfc2bfb8b4da601bb30de0344ae453aa1afe/Threat%20Intelligence/The%20DFIR%20Report/20210329_Sodinokibi_(aka_REvil)_Ransomware.yaml
author: Vadim Khrykov, Cyb3rEng
date: 2021-08-23
modified: 2023-02-14
tags:
    - attack.stealth
    - attack.t1204.002
    - attack.t1047
    - attack.t1218.010
    - attack.execution
logsource:
    product: windows
    category: process_creation
detection:
    selection_parent:
        ParentImage|endswith:
            - '\WINWORD.EXE'
            - '\EXCEL.EXE'
            - '\POWERPNT.exe'
            - '\MSPUB.exe'
            - '\VISIO.exe'
            - '\MSACCESS.EXE'
            - '\EQNEDT32.EXE'
            - '\ONENOTE.EXE'
            - '\wordpad.exe'
            - '\wordview.exe'
    selection_wmic_img:
        - Image|endswith: '\wbem\WMIC.exe'
        - OriginalFileName: 'wmic.exe'
    selection_wmic_cli:
        CommandLine|contains|all:
            - 'process'
            - 'create'
            - 'call'
        CommandLine|contains:
            # Add more suspicious LOLBINs as you see fit
            - 'regsvr32'
            - 'rundll32'
            - 'msiexec'
            - 'mshta'
            - 'verclsid'
            - 'wscript'
            - 'cscript'
    condition: all of selection_*
falsepositives:
    - Unknown
level: high

Original YAML and metadata in JSON

False positives

• Unknown

Source references

• https://thedfirreport.com/2021/03/29/sodinokibi-aka-revil-ransomware/
• https://github.com/vadim-hunter/Detection-Ideas-Rules/blob/02bcbfc2bfb8b4da601bb30de0344ae453aa1afe/Threat%20Intelligence/The%20DFIR%20Report/20210329_Sodinokibi_(aka_REvil)_Ransomware.yaml