Unsigned Mfdetours.DLL Sideloading — Sigma Rule

Rule metadata and linked tags

Author: Nasreddine Bencherchali (Nextron Systems). Source status: test; severity: high. Source dates: 2023-08-11 / not supplied.

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

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 6fa630a9dff44ea18b3b89f8f719e50edf14ffdb49f0777b7672871e03e71c46

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: Unsigned Mfdetours.DLL Sideloading
id: 948a0953-f287-4806-bbcb-3b2e396df89f
related:
    - id: d2605a99-2218-4894-8fd3-2afb7946514d
      type: similar
status: test
description: Detects DLL sideloading of unsigned "mfdetours.dll". Executing "mftrace.exe" can be abused to attach to an arbitrary process and force load any DLL named "mfdetours.dll" from the current directory of execution.
references:
    - Internal Research
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-08-11
tags:
    - attack.persistence
    - attack.privilege-escalation
    - attack.execution
    - attack.stealth
    - attack.t1574.001
logsource:
    category: image_load
    product: windows
detection:
    selection:
        ImageLoaded|endswith: '\mfdetours.dll'
    filter_main_legit_path:
        ImageLoaded|contains: ':\Program Files (x86)\Windows Kits\10\bin\'
        SignatureStatus: 'Valid'
    condition: selection and not 1 of filter_main_*
falsepositives:
    - Unlikely
level: high

Original YAML and metadata in JSON

False positives

• Unlikely

Source references

• Internal Research (source note; no public URL supplied)