UAC Bypass Using NTFS Reparse Point - Process — Sigma Rule

Rule metadata and linked tags

Author: Christian Burkard (Nextron Systems). Source status: test; severity: high. Source dates: 2021-08-30 / 2024-12-01.

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

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 93e6d2afb47b03665744f181e0c350984531a3cd2b072abe86af6c9a86fb9fd0

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: UAC Bypass Using NTFS Reparse Point - Process
id: 39ed3c80-e6a1-431b-9df3-911ac53d08a7
status: test
description: Detects the pattern of UAC Bypass using NTFS reparse point and wusa.exe DLL hijacking (UACMe 36)
references:
    - https://github.com/hfiref0x/UACME
author: Christian Burkard (Nextron Systems)
date: 2021-08-30
modified: 2024-12-01
tags:
    - attack.privilege-escalation
    - attack.t1548.002
logsource:
    category: process_creation
    product: windows
detection:
    selection1:
        CommandLine|startswith: '"C:\Windows\system32\wusa.exe"  /quiet C:\Users\'
        CommandLine|endswith: '\AppData\Local\Temp\update.msu'
        IntegrityLevel:
            - 'High'
            - 'System'
            - 'S-1-16-16384' # System
            - 'S-1-16-12288' # High
    selection2:
        ParentCommandLine: '"C:\Windows\system32\dism.exe" /online /quiet /norestart /add-package /packagepath:"C:\Windows\system32\pe386" /ignorecheck'
        IntegrityLevel:
            - 'High'
            - 'System'
        CommandLine|contains|all:
            - 'C:\Users\'
            - '\AppData\Local\Temp\'
            - '\dismhost.exe {'
        Image|endswith: '\DismHost.exe'
    condition: 1 of selection*
falsepositives:
    - Unknown
level: high

Original YAML and metadata in JSON

False positives

• Unknown

Source references

• https://github.com/hfiref0x/UACME