Sigma rule: Suspicious Userinit Child Process

A detection rule from the SigmaHQ repository, shown as its author published it. Dataset version ref-27c5820ebcaf, updated 2025-10-17T00:00:00.000Z.

Rule

Title
Suspicious Userinit Child Process
Status
test
Level
medium
Author
Florian Roth (Nextron Systems), Samir Bousseaden (idea)
Date
2019-06-17
Modified
2025-10-17
File
rules/windows/process_creation/proc_creation_win_susp_userinit_child.yml
Commit
ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects a suspicious child process of userinit

Log source

product
windows
category
process_creation

Detection

selection:
    ParentImage|endswith: '\userinit.exe'
filter_main_netlogon:
    CommandLine|contains: '\netlogon\'
filter_main_explorer:
    - Image|endswith: '\explorer.exe'
    - OriginalFileName: 'explorer.exe'
    - CommandLine: 'C:\Windows\Explorer.EXE'
filter_main_null:
    Image: null
condition: selection and not 1 of filter_main_*

False positives (as the rule lists them)

  • Administrative scripts

Tags

  • attack.privilege-escalation
  • attack.stealth
  • attack.t1055

MITRE ATT&CK ids this rule names

References

Read on 2026-11-03T00:58:21.399Z under licence sigma-drl-1.1@d5f4c36a from https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/process_creation/proc_creation_win_susp_userinit_child.yml

Sources and licences

  • SigmaHQ

    "Suspicious Userinit Child Process" by Florian Roth (Nextron Systems), Samir Bousseaden (idea) (SigmaHQ). Rule: https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/process_creation/proc_creation_win_susp_userinit_child.yml.
    Licensed under the Detection Rule License (DRL) 1.1: https://github.com/SigmaHQ/Detection-Rule-License

    Detection Rule License (DRL) 1.1

Cite this page

Dragons Eye Ransomware Tracker, "Sigma rule: Suspicious Userinit Child Process",
entity page, dataset version ref-27c5820ebcaf, updated 2025-10-17T00:00:00.000Z,
https://ransomware-tracker.com/detections/sigma/b655a06a-31c0-477a-95c2-3726b83d649d (accessed 2026-11-03).
Underlying source: SigmaHQ rule b655a06a-31c0-477a-95c2-3726b83d649d, commit ccbb0369507f796db0b0ae6854c8a2be471b9d84.

Pages change. The dataset version identifies the data, but no archive of old versions is kept, so this citation cannot be replayed later.