{"id":"6385697e-9f1b-40bd-8817-f4a91f40508e","title":"PowerShell Base64 Encoded Invoke Keyword","description":"Detects UTF-8 and UTF-16 Base64 encoded powershell 'Invoke-' calls","author":"pH-T (Nextron Systems), Harjot Singh, @cyb3rjy0t","status":"test","level":"high","date":"2022-05-20","modified":"2023-04-06","tags":["attack.execution","attack.stealth","attack.t1059.001","attack.t1027"],"technique_ids":["T1027","T1059.001"],"logsource":{"category":"process_creation","product":"windows"},"falsepositives":["Unknown"],"references":["https://thedfirreport.com/2022/05/09/seo-poisoning-a-gootloader-story/"],"source_path":"rules/windows/process_creation/proc_creation_win_powershell_base64_invoke.yml","source_sha256":"e6ad822eccdf3f7c3f0b6f6244251cbc2d8570ccb94ed02f1134c0fbc43b46be","source_url":"https://github.com/anpa1200/sigma/blob/b249e9683190cffdcaf188ccbfb90bf4759844e1/rules/windows/process_creation/proc_creation_win_powershell_base64_invoke.yml","license":"Detection Rule License 1.1","license_url":"https://github.com/SigmaHQ/Detection-Rule-License/blob/main/LICENSE.Detection.Rules.md","yaml":"title: PowerShell Base64 Encoded Invoke Keyword\nid: 6385697e-9f1b-40bd-8817-f4a91f40508e\nrelated:\n    - id: fd6e2919-3936-40c9-99db-0aa922c356f7\n      type: obsolete\nstatus: test\ndescription: Detects UTF-8 and UTF-16 Base64 encoded powershell 'Invoke-' calls\nreferences:\n    - https://thedfirreport.com/2022/05/09/seo-poisoning-a-gootloader-story/\nauthor: pH-T (Nextron Systems), Harjot Singh, @cyb3rjy0t\ndate: 2022-05-20\nmodified: 2023-04-06\ntags:\n    - attack.execution\n    - attack.stealth\n    - attack.t1059.001\n    - attack.t1027\nlogsource:\n    category: process_creation\n    product: windows\ndetection:\n    selection_img:\n        - Image|endswith:\n              - '\\powershell.exe'\n              - '\\pwsh.exe'\n        - OriginalFileName:\n              - 'PowerShell.EXE'\n              - 'pwsh.dll'\n    selection_cli_enc:\n        CommandLine|contains: ' -e'\n    selection_cli_invoke:\n        CommandLine|contains:\n            # Invoke-\n            # UTF-16LE\n            - 'SQBuAHYAbwBrAGUALQ'\n            - 'kAbgB2AG8AawBlAC0A'\n            - 'JAG4AdgBvAGsAZQAtA'\n            # UTF-8\n            - 'SW52b2tlL'\n            - 'ludm9rZS'\n            - 'JbnZva2Ut'\n    condition: all of selection_*\nfalsepositives:\n    - Unknown\nlevel: high\nsimulation:\n    - type: atomic red team\n      name: Create a Process using WMI Query and an Encoded Command\n      technique: T1047\n      atomic_guid: 7db7a7f9-9531-4840-9b30-46220135441c\nregression_tests_path: regression_data/rules/windows/process_creation/proc_creation_win_powershell_base64_invoke/info.yml\n","validation":"yaml_parsed_not_backend_compiled_or_live_validated","techniques":[{"key":"enterprise/T1027","id":"T1027","name":"Obfuscated Files or Information","page":"techniques/enterprise/T1027/"},{"key":"enterprise/T1059.001","id":"T1059.001","name":"PowerShell","page":"techniques/enterprise/T1059.001/"}],"data_path":"data/detection-rules/6385697e-9f1b-40bd-8817-f4a91f40508e.json","kind":"sigma"}