CLR DLL Loaded Via Office Applications — Sigma Rule

Rule metadata and linked tags

Author: Antonlovesdnb. Source status: test; severity: medium. Source dates: 2020-02-19 / 2023-03-29.

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

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: dcc0e789f2c451250d7862b2271c381414efaa5036798ddc13fc650bf8d876b0

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: CLR DLL Loaded Via Office Applications
id: d13c43f0-f66b-4279-8b2c-5912077c1780
status: test
description: Detects CLR DLL being loaded by an Office Product
references:
    - https://medium.com/threatpunter/detecting-adversary-tradecraft-with-image-load-event-logging-and-eql-8de93338c16
author: Antonlovesdnb
date: 2020-02-19
modified: 2023-03-29
tags:
    - attack.execution
    - attack.t1204.002
logsource:
    category: image_load
    product: windows
detection:
    selection:
        Image|endswith:
            - '\excel.exe'
            - '\mspub.exe'
            - '\outlook.exe'
            - '\onenote.exe'
            - '\onenoteim.exe' # Just in case
            - '\powerpnt.exe'
            - '\winword.exe'
        ImageLoaded|contains: '\clr.dll'
    condition: selection
falsepositives:
    - Unknown
level: medium

Original YAML and metadata in JSON

False positives

• Unknown

Source references

• https://medium.com/threatpunter/detecting-adversary-tradecraft-with-image-load-event-logging-and-eql-8de93338c16