Suspicious Userinit Child Process

 1title: Suspicious Userinit Child Process
 2id: b655a06a-31c0-477a-95c2-3726b83d649d
 3status: test
 4description: Detects a suspicious child process of userinit
 5references:
 6    - https://twitter.com/SBousseaden/status/1139811587760562176
 7author: Florian Roth (Nextron Systems), Samir Bousseaden (idea)
 8date: 2019-06-17
 9modified: 2025-10-17
10tags:
11    - attack.privilege-escalation
12    - attack.defense-evasion
13    - attack.t1055
14logsource:
15    category: process_creation
16    product: windows
17detection:
18    selection:
19        ParentImage|endswith: '\userinit.exe'
20    filter_main_netlogon:
21        CommandLine|contains: '\netlogon\'
22    filter_main_explorer:
23        - Image|endswith: '\explorer.exe'
24        - OriginalFileName: 'explorer.exe'
25        - CommandLine: 'C:\Windows\Explorer.EXE'
26    filter_main_null:
27        Image: null
28    condition: selection and not 1 of filter_main_*
29fields:
30    - CommandLine
31    - ParentCommandLine
32falsepositives:
33    - Administrative scripts
34level: medium