Detectionhightest

Rare Remote Thread Creation By Uncommon Source Image

Detects uncommon processes creating remote threads.

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Perez Diego, oscd.communityCreated Sun Oct 27Updated Mon Dec 0802d1d718-dd13-41af-989d-ea85c7fab93fwindows

Log Source

WindowsRemote Thread Creation

ProductWindows← raw: windows

CategoryRemote Thread Creation← raw: create_remote_thread

Detection Logic

detection:
    selection:
        SourceImage|endswith:
            - '\bash.exe'
            - '\cscript.exe'
            - '\cvtres.exe'
            - '\defrag.exe'
            - '\dialer.exe'
            - '\dnx.exe'
            - '\esentutl.exe'
            - '\excel.exe'
            - '\expand.exe'
            - '\find.exe'
            - '\findstr.exe'
            - '\forfiles.exe'
            - '\gpupdate.exe'
            - '\hh.exe'
            - '\installutil.exe'
            - '\lync.exe'
            - '\makecab.exe'
            - '\mDNSResponder.exe'
            - '\monitoringhost.exe' # Loads .NET CLR by default and thus a favorite for process injection for .NET in-memory offensive tools.
            - '\msbuild.exe'
            - '\mshta.exe'
            - '\mspaint.exe'
            - '\outlook.exe'
            - '\ping.exe'
            - '\provtool.exe'
            - '\python.exe'
            - '\regsvr32.exe'
            - '\robocopy.exe'
            - '\runonce.exe'
            - '\sapcimc.exe'
            - '\smartscreen.exe'
            - '\spoolsv.exe'
            - '\tstheme.exe'
            - '\userinit.exe'
            - '\vssadmin.exe'
            - '\vssvc.exe'
            - '\w3wp.exe'
            - '\winscp.exe'
            - '\winword.exe'
            - '\wmic.exe'
            - '\wscript.exe'
    filter_main_conhost:
        SourceImage:
            - 'C:\Windows\System32\Defrag.exe'
            - 'C:\Windows\System32\makecab.exe'
        TargetImage: 'C:\Windows\System32\conhost.exe'
    filter_main_provtol_svchost:
        SourceImage: 'C:\Windows\System32\provtool.exe'
        TargetImage: 'C:\Windows\System32\svchost.exe'
    filter_main_provtool_system:
        SourceImage: 'C:\Windows\System32\provtool.exe'
        TargetImage: 'System'
    filter_main_userinit:
        SourceImage: 'C:\Windows\System32\userinit.exe'
        TargetImage: 'C:\Windows\explorer.exe'
    filter_main_winword:
        SourceImage|endswith: '\WINWORD.EXE'
        TargetImage|startswith:
            - 'C:\Program Files (x86)\' # C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe
            - 'C:\Program Files\' # C:\Program Files\Microsoft Office\root\vfs\ProgramFilesCommonX64\Microsoft Shared\Office16\AI\ai.exe
    filter_main_ms_office:
        # Raised by following issue: https://github.com/SigmaHQ/sigma/issues/5529
        SourceImage|startswith:
            - 'C:\Program Files\Microsoft Office\'
            - 'C:\Program Files (x86)\Microsoft Office\'
        TargetImage: 'System'
    filter_optional_explorer_vmtools:
        SourceImage|endswith: '\SysWOW64\explorer.exe'
        TargetImage:
            - 'C:\Program Files (x86)\VMware\VMware Tools\vmtoolsd.exe'
            - 'C:\Program Files\VMware\VMware Tools\vmtoolsd.exe'
    condition: selection and not 1 of filter_main_* and not 1 of filter_optional_*