Potential WWlib.DLL Sideloading — Sigma Rule

Rule metadata and linked tags

Author: X__Junior (Nextron Systems). Source status: test; severity: medium. Source dates: 2023-05-18 / not supplied.

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

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: ad6aa7555a0ac1b6b54717831332b50ec522cddd057d4a58fd20e6224d0f4e8d

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: Potential WWlib.DLL Sideloading
id: e2e01011-5910-4267-9c3b-4149ed5479cf
status: test
description: Detects potential DLL sideloading of "wwlib.dll"
references:
    - https://twitter.com/WhichbufferArda/status/1658829954182774784
    - https://news.sophos.com/en-us/2022/11/03/family-tree-dll-sideloading-cases-may-be-related/
    - https://securelist.com/apt-luminousmoth/103332/
author: X__Junior (Nextron Systems)
date: 2023-05-18
tags:
    - attack.persistence
    - attack.privilege-escalation
    - attack.execution
    - attack.stealth
    - attack.t1574.001
logsource:
    category: image_load
    product: windows
detection:
    selection:
        ImageLoaded|endswith: '\wwlib.dll'
    filter_main_path:
        Image|startswith:
            - 'C:\Program Files (x86)\Microsoft Office\'
            - 'C:\Program Files\Microsoft Office\'
        Image|endswith: '\winword.exe'
        ImageLoaded|startswith:
            - 'C:\Program Files (x86)\Microsoft Office\'
            - 'C:\Program Files\Microsoft Office\'
    condition: selection and not 1 of filter_main_*
falsepositives:
    - Unknown
level: medium

Original YAML and metadata in JSON

False positives

• Unknown

Source references

• https://twitter.com/WhichbufferArda/status/1658829954182774784
• https://news.sophos.com/en-us/2022/11/03/family-tree-dll-sideloading-cases-may-be-related/
• https://securelist.com/apt-luminousmoth/103332/