Detectionmediumtest

Process Creation Using Sysnative Folder

Detects process creation events that use the Sysnative folder (common for CobaltStrike spawns)

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Max Altgelt (Nextron Systems)Created Tue Aug 23Updated Wed Oct 083c1b5fb0-c72f-45ba-abd1-4d4c353144abwindows

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:
        - CommandLine|contains: ':\Windows\Sysnative\'
        - Image|contains: ':\Windows\Sysnative\'
    filter_main_ngen:
        Image|contains:
            - 'C:\Windows\Microsoft.NET\Framework64\v'
            - 'C:\Windows\Microsoft.NET\Framework\v'
            - 'C:\Windows\Microsoft.NET\FrameworkArm\v'
            - 'C:\Windows\Microsoft.NET\FrameworkArm64\v'
        Image|endswith: '\ngen.exe'
        CommandLine|contains: 'install'
    filter_optional_xampp:
        CommandLine|contains|all:
            - '"C:\Windows\sysnative\cmd.exe"'
            - '\xampp\'
            - '\catalina_start.bat'
    condition: selection and not 1 of filter_main_* and not 1 of filter_optional_*