Detectionmediumtest

Potential Persistence Via Visual Studio Tools for Office

Detects persistence via Visual Studio Tools for Office (VSTO) add-ins in Office applications.

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Bhabesh RajCreated Sun Jan 10Updated Tue Oct 079d15044a-7cfe-4d23-8085-6ebc11df7685windows

Log Source

WindowsRegistry Set

ProductWindows← raw: windows

CategoryRegistry Set← raw: registry_set

Detection Logic

detection:
    selection:
        TargetObject|contains:
            - '\Software\Microsoft\Office\Outlook\Addins\'
            - '\Software\Microsoft\Office\Word\Addins\'
            - '\Software\Microsoft\Office\Excel\Addins\'
            - '\Software\Microsoft\Office\Powerpoint\Addins\'
            - '\Software\Microsoft\VSTO\Security\Inclusion\'
    filter_main_system:
        Image:
            - 'C:\Windows\System32\msiexec.exe'
            - 'C:\Windows\SysWOW64\msiexec.exe'
            - 'C:\Windows\System32\regsvr32.exe'
            - 'C:\Windows\SysWOW64\regsvr32.exe' # e.g. default Evernote installation
    filter_main_office_click_to_run:
        Image|startswith:
            - 'C:\Program Files\Common Files (x86)\Microsoft Shared\ClickToRun\'
            - 'C:\Program Files\Common Files\Microsoft Shared\ClickToRun\'
        Image|endswith: '\OfficeClickToRun.exe'
    filter_main_integrator:
        Image:
            - 'C:\Program Files (x86)\Microsoft Office\root\integration\integrator.exe'
            - 'C:\Program Files\Microsoft Office\root\integration\integrator.exe'
    filter_main_office_apps:
        Image|startswith:
            - 'C:\Program Files\Microsoft Office\OFFICE'
            - 'C:\Program Files (x86)\Microsoft Office\OFFICE'
            - 'C:\Program Files\Microsoft Office\Root\OFFICE'
            - 'C:\Program Files (x86)\Microsoft Office\Root\OFFICE'
        Image|endswith:
            - '\excel.exe'
            - '\Integrator.exe'
            - '\outlook.exe'
            - '\powerpnt.exe'
            - '\Teams.exe'
            - '\visio.exe'
            - '\winword.exe'
    filter_optional_avg:
        Image:
            - 'C:\Program Files\AVG\Antivirus\RegSvr.exe'
            - 'C:\Program Files (x86)\AVG\Antivirus\RegSvr.exe'
        TargetObject|contains: '\Microsoft\Office\Outlook\Addins\Antivirus.AsOutExt\'
    filter_optional_avast:
        Image:
            - 'C:\Program Files\Avast Software\Avast\RegSvr.exe'
            - 'C:\Program Files (x86)\Avast Software\Avast\RegSvr.exe'
        TargetObject|contains: '\Microsoft\Office\Outlook\Addins\Avast.AsOutExt\'
    condition: selection and not 1 of filter_main_* and not 1 of filter_optional_*