{"id":"9d15044a-7cfe-4d23-8085-6ebc11df7685","title":"Potential Persistence Via Visual Studio Tools for Office","description":"Detects persistence via Visual Studio Tools for Office (VSTO) add-ins in Office applications.","author":"Bhabesh Raj","status":"test","level":"medium","date":"2021-01-10","modified":"2026-01-09","tags":["attack.t1137.006","attack.persistence"],"technique_ids":["T1137.006"],"logsource":{"category":"registry_set","product":"windows"},"falsepositives":["Legitimate Addin Installation"],"references":["https://twitter.com/_vivami/status/1347925307643355138","https://vanmieghem.io/stealth-outlook-persistence/"],"source_path":"rules/windows/registry/registry_set/registry_set_persistence_office_vsto.yml","source_sha256":"dafbab16956b6a66c8c1d52f484d91779ac9299569e4abccdc8d64a780262a10","source_url":"https://github.com/anpa1200/sigma/blob/b249e9683190cffdcaf188ccbfb90bf4759844e1/rules/windows/registry/registry_set/registry_set_persistence_office_vsto.yml","license":"Detection Rule License 1.1","license_url":"https://github.com/SigmaHQ/Detection-Rule-License/blob/main/LICENSE.Detection.Rules.md","yaml":"title: Potential Persistence Via Visual Studio Tools for Office\nid: 9d15044a-7cfe-4d23-8085-6ebc11df7685\nstatus: test\ndescription: Detects persistence via Visual Studio Tools for Office (VSTO) add-ins in Office applications.\nreferences:\n    - https://twitter.com/_vivami/status/1347925307643355138\n    - https://vanmieghem.io/stealth-outlook-persistence/\nauthor: Bhabesh Raj\ndate: 2021-01-10\nmodified: 2026-01-09\ntags:\n    - attack.t1137.006\n    - attack.persistence\nlogsource:\n    category: registry_set\n    product: windows\ndetection:\n    selection:\n        TargetObject|contains:\n            - '\\Software\\Microsoft\\Office\\Outlook\\Addins\\'\n            - '\\Software\\Microsoft\\Office\\Word\\Addins\\'\n            - '\\Software\\Microsoft\\Office\\Excel\\Addins\\'\n            - '\\Software\\Microsoft\\Office\\Powerpoint\\Addins\\'\n            - '\\Software\\Microsoft\\VSTO\\Security\\Inclusion\\'\n    filter_main_system:\n        Image:\n            - 'C:\\Windows\\System32\\msiexec.exe'\n            - 'C:\\Windows\\SysWOW64\\msiexec.exe'\n            - 'C:\\Windows\\System32\\regsvr32.exe'\n            - 'C:\\Windows\\SysWOW64\\regsvr32.exe' # e.g. default Evernote installation\n    filter_main_office_click_to_run:\n        Image|startswith:\n            - 'C:\\Program Files\\Common Files (x86)\\Microsoft Shared\\ClickToRun\\'\n            - 'C:\\Program Files\\Common Files\\Microsoft Shared\\ClickToRun\\'\n        Image|endswith: '\\OfficeClickToRun.exe'\n    filter_main_integrator:\n        Image:\n            - 'C:\\Program Files (x86)\\Microsoft Office\\root\\integration\\integrator.exe'\n            - 'C:\\Program Files\\Microsoft Office\\root\\integration\\integrator.exe'\n    filter_main_office_apps:\n        Image|startswith:\n            - 'C:\\Program Files\\Microsoft Office\\OFFICE'\n            - 'C:\\Program Files (x86)\\Microsoft Office\\OFFICE'\n            - 'C:\\Program Files\\Microsoft Office\\Root\\OFFICE'\n            - 'C:\\Program Files (x86)\\Microsoft Office\\Root\\OFFICE'\n            - 'C:\\PROGRA~2\\MICROS~2\\Office'\n        Image|endswith:\n            - '\\excel.exe'\n            - '\\Integrator.exe'\n            - '\\OneNote.exe'\n            - '\\outlook.exe'\n            - '\\powerpnt.exe'\n            - '\\Teams.exe'\n            - '\\visio.exe'\n            - '\\winword.exe'\n    filter_main_vsto:\n        Image|startswith:\n            - 'C:\\Program Files\\Common Files\\Microsoft Shared\\VSTO\\'\n            - 'C:\\Program Files (x86)\\Microsoft Shared\\VSTO\\'\n        Image|endswith: '\\VSTOInstaller.exe'\n    filter_optional_avg:\n        Image:\n            - 'C:\\Program Files\\AVG\\Antivirus\\RegSvr.exe'\n            - 'C:\\Program Files (x86)\\AVG\\Antivirus\\RegSvr.exe'\n        TargetObject|contains: '\\Microsoft\\Office\\Outlook\\Addins\\Antivirus.AsOutExt\\'\n    filter_optional_avast:\n        Image:\n            - 'C:\\Program Files\\Avast Software\\Avast\\RegSvr.exe'\n            - 'C:\\Program Files (x86)\\Avast Software\\Avast\\RegSvr.exe'\n        TargetObject|contains: '\\Microsoft\\Office\\Outlook\\Addins\\Avast.AsOutExt\\'\n    condition: selection and not 1 of filter_main_* and not 1 of filter_optional_*\nfalsepositives:\n    - Legitimate Addin Installation\nlevel: medium\n","validation":"yaml_parsed_not_backend_compiled_or_live_validated","techniques":[{"key":"enterprise/T1137.006","id":"T1137.006","name":"Add-ins","page":"techniques/enterprise/T1137.006/"}],"data_path":"data/detection-rules/9d15044a-7cfe-4d23-8085-6ebc11df7685.json","kind":"sigma"}