{"id":"7a922f1b-2635-4d6c-91ef-af228b198ad3","title":"Invoke-Obfuscation COMPRESS OBFUSCATION - Security","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","service":"security","definition":"The 'System Security Extension' audit subcategory need to be enabled to log the EID 4697"},"falsepositives":["Unknown"],"references":["https://github.com/SigmaHQ/sigma/issues/1009"],"source_path":"rules/windows/builtin/security/win_security_invoke_obfuscation_via_compress_services_security.yml","source_sha256":"3fbb0397bc63c6983ac9a97d28d3b0a77d88a1a42041e3a35caaf29ef948ce3e","source_url":"https://github.com/anpa1200/sigma/blob/b249e9683190cffdcaf188ccbfb90bf4759844e1/rules/windows/builtin/security/win_security_invoke_obfuscation_via_compress_services_security.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 - Security\nid: 7a922f1b-2635-4d6c-91ef-af228b198ad3\nrelated:\n    - id: 175997c5-803c-4b08-8bb0-70b099f47595\n      type: derived\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    service: security\n    definition: The 'System Security Extension' audit subcategory need to be enabled to log the EID 4697\ndetection:\n    selection:\n        EventID: 4697\n        ServiceFileName|contains|all:\n            - 'new-object'\n            - 'text.encoding]::ascii'\n            - 'readtoend'\n        ServiceFileName|contains:\n            - 'system.io.compression.deflatestream'\n            - 'system.io.streamreader'\n    condition: selection\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/7a922f1b-2635-4d6c-91ef-af228b198ad3.json","kind":"sigma"}