{"id":"b3512211-c67e-4707-bedc-66efc7848863","title":"Potential PowerShell Downgrade Attack","description":"Detects PowerShell downgrade attack by comparing the host versions with the actually used engine version 2.0","author":"Harish Segar (rule)","status":"test","level":"medium","date":"2020-03-20","modified":"2023-01-04","tags":["attack.execution","attack.t1059.001"],"technique_ids":["T1059.001"],"logsource":{"category":"process_creation","product":"windows"},"falsepositives":["Unknown"],"references":["http://www.leeholmes.com/blog/2017/03/17/detecting-and-preventing-powershell-downgrade-attacks/","https://github.com/r00t-3xp10it/hacking-material-books/blob/43cb1e1932c16ff1f58b755bc9ab6b096046853f/obfuscation/simple_obfuscation.md#bypass-or-avoid-amsi-by-version-downgrade-"],"source_path":"rules/windows/process_creation/proc_creation_win_powershell_downgrade_attack.yml","source_sha256":"996dcaba3cbb61198b6ebbc6dfc3b9dda0e935ab3343430e62a43ec6d58e052f","source_url":"https://github.com/anpa1200/sigma/blob/b249e9683190cffdcaf188ccbfb90bf4759844e1/rules/windows/process_creation/proc_creation_win_powershell_downgrade_attack.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 PowerShell Downgrade Attack\nid: b3512211-c67e-4707-bedc-66efc7848863\nrelated:\n    - id: 6331d09b-4785-4c13-980f-f96661356249\n      type: derived\nstatus: test\ndescription: Detects PowerShell downgrade attack by comparing the host versions with the actually used engine version 2.0\nreferences:\n    - http://www.leeholmes.com/blog/2017/03/17/detecting-and-preventing-powershell-downgrade-attacks/\n    - https://github.com/r00t-3xp10it/hacking-material-books/blob/43cb1e1932c16ff1f58b755bc9ab6b096046853f/obfuscation/simple_obfuscation.md#bypass-or-avoid-amsi-by-version-downgrade-\nauthor: Harish Segar (rule)\ndate: 2020-03-20\nmodified: 2023-01-04\ntags:\n    - attack.execution\n    - attack.t1059.001\nlogsource:\n    category: process_creation\n    product: windows\ndetection:\n    selection:\n        Image|endswith: '\\powershell.exe'\n        CommandLine|contains:\n            - ' -version 2 '\n            - ' -versio 2 '\n            - ' -versi 2 '\n            - ' -vers 2 '\n            - ' -ver 2 '\n            - ' -ve 2 '\n            - ' -v 2 '\n    condition: selection\nfalsepositives:\n    - Unknown\nlevel: medium\n","validation":"yaml_parsed_not_backend_compiled_or_live_validated","techniques":[{"key":"enterprise/T1059.001","id":"T1059.001","name":"PowerShell","page":"techniques/enterprise/T1059.001/"}],"data_path":"data/detection-rules/b3512211-c67e-4707-bedc-66efc7848863.json","kind":"sigma"}