{"id":"1e0e1a81-e79b-44bc-935b-ddb9c8006b3d","title":"Potential Script Proxy Execution Via CL_Mutexverifiers.ps1","description":"Detects the use of the Microsoft signed script \"CL_mutexverifiers\" to proxy the execution of additional PowerShell script commands","author":"Nasreddine Bencherchali (Nextron Systems), oscd.community, Natalia Shornikova, frack113","status":"test","level":"medium","date":"2022-05-21","modified":"2023-08-17","tags":["attack.stealth","attack.t1216"],"technique_ids":["T1216"],"logsource":{"category":"process_creation","product":"windows"},"falsepositives":["Unknown"],"references":["https://lolbas-project.github.io/lolbas/Scripts/CL_mutexverifiers/"],"source_path":"rules/windows/process_creation/proc_creation_win_powershell_cl_mutexverifiers.yml","source_sha256":"e503018613d39b2bfa187d2050ac06715d81e435cb7075f6900a375c638ebde8","source_url":"https://github.com/anpa1200/sigma/blob/b249e9683190cffdcaf188ccbfb90bf4759844e1/rules/windows/process_creation/proc_creation_win_powershell_cl_mutexverifiers.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 Script Proxy Execution Via CL_Mutexverifiers.ps1\nid: 1e0e1a81-e79b-44bc-935b-ddb9c8006b3d\nstatus: test\ndescription: Detects the use of the Microsoft signed script \"CL_mutexverifiers\" to proxy the execution of additional PowerShell script commands\nreferences:\n    - https://lolbas-project.github.io/lolbas/Scripts/CL_mutexverifiers/\nauthor: Nasreddine Bencherchali (Nextron Systems), oscd.community, Natalia Shornikova, frack113\ndate: 2022-05-21\nmodified: 2023-08-17\ntags:\n    - attack.stealth\n    - attack.t1216\nlogsource:\n    category: process_creation\n    product: windows\ndetection:\n    selection_pwsh:\n        ParentImage|endswith:\n            # Note: to avoid potential FPs we assume the script was launched from powershell. But in theory it can be launched by any Powershell like process\n            - '\\powershell.exe'\n            - '\\pwsh.exe'\n        Image|endswith: '\\powershell.exe'\n        CommandLine|contains: ' -nologo -windowstyle minimized -file '\n    selection_temp:\n        # Note: Since the function uses \"env:temp\" the value will change depending on the context of exec\n        CommandLine|contains:\n            - '\\AppData\\Local\\Temp\\'\n            - '\\Windows\\Temp\\'\n    condition: all of selection_*\nfalsepositives:\n    - Unknown\nlevel: medium\n","validation":"yaml_parsed_not_backend_compiled_or_live_validated","techniques":[{"key":"enterprise/T1216","id":"T1216","name":"System Script Proxy Execution","page":"techniques/enterprise/T1216/"}],"data_path":"data/detection-rules/1e0e1a81-e79b-44bc-935b-ddb9c8006b3d.json","kind":"sigma"}