{"id":"88f680b8-070e-402c-ae11-d2914f2257f1","title":"PowerShell Base64 Encoded IEX Cmdlet","description":"Detects usage of a base64 encoded \"IEX\" cmdlet in a process command line","author":"Florian Roth (Nextron Systems)","status":"test","level":"high","date":"2019-08-23","modified":"2023-04-06","tags":["attack.execution","attack.t1059.001"],"technique_ids":["T1059.001"],"logsource":{"category":"process_creation","product":"windows"},"falsepositives":["Unknown"],"references":["Internal Research"],"source_path":"rules/windows/process_creation/proc_creation_win_powershell_base64_iex.yml","source_sha256":"7d2d5e96ae03d6a5798f5bc3fa80190849826288a2f32ced56cea7cb31ea62fe","source_url":"https://github.com/anpa1200/sigma/blob/b249e9683190cffdcaf188ccbfb90bf4759844e1/rules/windows/process_creation/proc_creation_win_powershell_base64_iex.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 IEX Cmdlet\nid: 88f680b8-070e-402c-ae11-d2914f2257f1\nstatus: test\ndescription: Detects usage of a base64 encoded \"IEX\" cmdlet in a process command line\nreferences:\n    - Internal Research\nauthor: Florian Roth (Nextron Systems)\ndate: 2019-08-23\nmodified: 2023-04-06\ntags:\n    - attack.execution\n    - attack.t1059.001\nlogsource:\n    category: process_creation\n    product: windows\ndetection:\n    selection:\n        - CommandLine|base64offset|contains:\n              - 'IEX (['\n              - 'iex (['\n              - 'iex (New'\n              - 'IEX (New'\n              - 'IEX(['\n              - 'iex(['\n              - 'iex(New'\n              - 'IEX(New'\n              - \"IEX(('\"\n              - \"iex(('\"\n        # UTF16 LE\n        - CommandLine|contains:\n              - 'SQBFAFgAIAAoAFsA'\n              - 'kARQBYACAAKABbA'\n              - 'JAEUAWAAgACgAWw'\n              - 'aQBlAHgAIAAoAFsA'\n              - 'kAZQB4ACAAKABbA'\n              - 'pAGUAeAAgACgAWw'\n              - 'aQBlAHgAIAAoAE4AZQB3A'\n              - 'kAZQB4ACAAKABOAGUAdw'\n              - 'pAGUAeAAgACgATgBlAHcA'\n              - 'SQBFAFgAIAAoAE4AZQB3A'\n              - 'kARQBYACAAKABOAGUAdw'\n              - 'JAEUAWAAgACgATgBlAHcA'\n    condition: selection\nfalsepositives:\n    - Unknown\nlevel: high\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/88f680b8-070e-402c-ae11-d2914f2257f1.json","kind":"sigma"}