Detectionmediumtest

Suspicious Userinit Child Process

Detects a suspicious child process of userinit

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Florian Roth (Nextron Systems), Samir BousseadenCreated Mon Jun 17Updated Fri Oct 17b655a06a-31c0-477a-95c2-3726b83d649dwindows

Log Source

WindowsProcess Creation

ProductWindows← raw: windows

CategoryProcess Creation← raw: process_creation

Events generated when a new process is spawned on the system. Covers command-line arguments, parent/child relationships, and process metadata.

Detection Logic

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_*