{"id":"ab37a6ec-6068-432b-a64e-2c7bf95b1d22","title":"Scripting/CommandLine Process Spawned Regsvr32","description":"Detects various command line and scripting engines/processes such as \"PowerShell\", \"Wscript\", \"Cmd\", etc. spawning a \"regsvr32\" instance.","author":"Florian Roth (Nextron Systems), Nasreddine Bencherchali (Nextron Systems)","status":"test","level":"medium","date":"2023-05-26","modified":"","tags":["attack.stealth","attack.t1218.010"],"technique_ids":["T1218.010"],"logsource":{"category":"process_creation","product":"windows"},"falsepositives":["Legitimate \".bat\", \".hta\", \".ps1\" or \".vbs\" scripts leverage legitimately often. Apply additional filter and exclusions as necessary","Some legitimate Windows services"],"references":["https://web.archive.org/web/20171001085340/https://subt0x10.blogspot.com/2017/04/bypass-application-whitelisting-script.html","https://app.any.run/tasks/34221348-072d-4b70-93f3-aa71f6ebecad/"],"source_path":"rules/windows/process_creation/proc_creation_win_regsvr32_susp_parent.yml","source_sha256":"14ca4424714aceb1836053f17196e1bb347f9593f8f615e841d7971cc570a8bc","source_url":"https://github.com/anpa1200/sigma/blob/b249e9683190cffdcaf188ccbfb90bf4759844e1/rules/windows/process_creation/proc_creation_win_regsvr32_susp_parent.yml","license":"Detection Rule License 1.1","license_url":"https://github.com/SigmaHQ/Detection-Rule-License/blob/main/LICENSE.Detection.Rules.md","yaml":"title: Scripting/CommandLine Process Spawned Regsvr32\nid: ab37a6ec-6068-432b-a64e-2c7bf95b1d22\nrelated:\n    - id: 8e2b24c9-4add-46a0-b4bb-0057b4e6187d\n      type: obsolete\nstatus: test\ndescription: Detects various command line and scripting engines/processes such as \"PowerShell\", \"Wscript\", \"Cmd\", etc. spawning a \"regsvr32\" instance.\nreferences:\n    - https://web.archive.org/web/20171001085340/https://subt0x10.blogspot.com/2017/04/bypass-application-whitelisting-script.html\n    - https://app.any.run/tasks/34221348-072d-4b70-93f3-aa71f6ebecad/\nauthor: Florian Roth (Nextron Systems), Nasreddine Bencherchali (Nextron Systems)\ndate: 2023-05-26\ntags:\n    - attack.stealth\n    - attack.t1218.010\nlogsource:\n    category: process_creation\n    product: windows\ndetection:\n    selection:\n        ParentImage|endswith:\n            - '\\cmd.exe'\n            - '\\cscript.exe'\n            - '\\mshta.exe'\n            - '\\powershell_ise.exe'\n            - '\\powershell.exe'\n            - '\\pwsh.exe'\n            - '\\wscript.exe'\n        Image|endswith: '\\regsvr32.exe'\n    filter_main_rpcproxy:\n        ParentImage: C:\\Windows\\System32\\cmd.exe\n        CommandLine|endswith: ' /s C:\\Windows\\System32\\RpcProxy\\RpcProxy.dll'\n    condition: selection and not 1 of filter_main_*\nfalsepositives:\n    - Legitimate \".bat\", \".hta\", \".ps1\" or \".vbs\" scripts leverage legitimately often. Apply additional filter and exclusions as necessary\n    - Some legitimate Windows services\nlevel: medium # Can be reduced to low if you experience a ton of FP\n","validation":"yaml_parsed_not_backend_compiled_or_live_validated","techniques":[{"key":"enterprise/T1218.010","id":"T1218.010","name":"Regsvr32","page":"techniques/enterprise/T1218.010/"}],"data_path":"data/detection-rules/ab37a6ec-6068-432b-a64e-2c7bf95b1d22.json","kind":"sigma"}