title: Explorer NOUACCHECK Flag
id: 534f2ef7-e8a2-4433-816d-c91bccde289b
status: test
description: Detects suspicious starts of explorer.exe that use the /NOUACCHECK flag that allows to run all sub processes of that newly started explorer.exe without any UAC checks
author: Florian Roth
references:
  - https://twitter.com/ORCA6665/status/1496478087244095491
date: 2022/02/23
modified: 2022/04/21
logsource:
  category: process_creation
  product: windows
detection:
  selection:
    Image|endswith: '\explorer.exe'
    CommandLine|contains: '/NOUACCHECK'
  filter_dc_logon:
    - ParentCommandLine: 'C:\Windows\system32\svchost.exe -k netsvcs -p -s Schedule'
    - ParentImage: 'C:\Windows\System32\svchost.exe'  # coarse filter needed for ID 4688 Events
  condition: selection and not 1 of filter_*
falsepositives:
  - Domain Controller User Logon
  - Unknown how many legitimate software products use that method
level: high
tags:
  - attack.defense_evasion
  - attack.t1548.002
