{"id":"20e5497e-331c-4cd5-8d36-935f6e2a9a07","title":"Invoke-Obfuscation COMPRESS OBFUSCATION - PowerShell","description":"Detects Obfuscated Powershell via COMPRESS OBFUSCATION","author":"Timur Zinniatullin, oscd.community","status":"test","level":"medium","date":"2020-10-18","modified":"2022-11-29","tags":["attack.stealth","attack.t1027","attack.execution","attack.t1059.001"],"technique_ids":["T1027","T1059.001"],"logsource":{"product":"windows","category":"ps_script","definition":"Requirements: Script Block Logging must be enabled"},"falsepositives":["Unknown"],"references":["https://github.com/SigmaHQ/sigma/issues/1009"],"source_path":"rules/windows/powershell/powershell_script/posh_ps_invoke_obfuscation_via_compress.yml","source_sha256":"199d2dc23f8f69d6f9323fd76c8b7fcb98e83ea4e66d2cc9d2320c4e1d51435f","source_url":"https://github.com/anpa1200/sigma/blob/b249e9683190cffdcaf188ccbfb90bf4759844e1/rules/windows/powershell/powershell_script/posh_ps_invoke_obfuscation_via_compress.yml","license":"Detection Rule License 1.1","license_url":"https://github.com/SigmaHQ/Detection-Rule-License/blob/main/LICENSE.Detection.Rules.md","yaml":"title: Invoke-Obfuscation COMPRESS OBFUSCATION - PowerShell\nid: 20e5497e-331c-4cd5-8d36-935f6e2a9a07\nstatus: test\ndescription: Detects Obfuscated Powershell via COMPRESS OBFUSCATION\nreferences:\n    - https://github.com/SigmaHQ/sigma/issues/1009 # (Task 19)\nauthor: Timur Zinniatullin, oscd.community\ndate: 2020-10-18\nmodified: 2022-11-29\ntags:\n    - attack.stealth\n    - attack.t1027\n    - attack.execution\n    - attack.t1059.001\nlogsource:\n    product: windows\n    category: ps_script\n    definition: 'Requirements: Script Block Logging must be enabled'\ndetection:\n    selection_4104:\n        ScriptBlockText|contains|all:\n            - 'new-object'\n            - 'text.encoding]::ascii'\n        ScriptBlockText|contains:\n            - 'system.io.compression.deflatestream'\n            - 'system.io.streamreader'\n        ScriptBlockText|endswith: 'readtoend'\n    condition: selection_4104\nfalsepositives:\n    - Unknown\nlevel: medium\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/20e5497e-331c-4cd5-8d36-935f6e2a9a07.json","kind":"sigma"}