Detectionmediumstable

WmiPrvSE Spawned A Process

Detects WmiPrvSE spawning a process

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Launch
Roberto Rodriguez (Cyb3rWard0g)Created Thu Aug 15Updated Thu Mar 23d21374ff-f574-44a7-9998-4a8c8bf33d7dwindows
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 Logic6 selectors
detection:
    selection:
        ParentImage|endswith: '\WmiPrvSe.exe'
    filter_logonid:
        LogonId:
            - '0x3e7'  # LUID 999 for SYSTEM
            - 'null'   # too many false positives
    filter_system_user:
        User|contains: # covers many language settings
            - 'AUTHORI'
            - 'AUTORI'
    filter_wmiprvse:
        Image|endswith: '\WmiPrvSE.exe'
    filter_werfault:
        Image|endswith: '\WerFault.exe'
    filter_null:  # some backends need the null value in a separate expression
        LogonId: null
    condition: selection and not 1 of filter_*
False Positives

False positives are expected (e.g. in environments where WinRM is used legitimately)