{"id":"3c1b5fb0-c72f-45ba-abd1-4d4c353144ab","title":"Process Creation Using Sysnative Folder","description":"Detects process creation events that use the Sysnative folder (common for CobaltStrike spawns)","author":"Max Altgelt (Nextron Systems)","status":"test","level":"medium","date":"2022-08-23","modified":"2025-10-08","tags":["attack.privilege-escalation","attack.stealth","attack.t1055"],"technique_ids":["T1055"],"logsource":{"category":"process_creation","product":"windows"},"falsepositives":["Unknown"],"references":["https://thedfirreport.com/2021/08/29/cobalt-strike-a-defenders-guide/"],"source_path":"rules/windows/process_creation/proc_creation_win_susp_sysnative.yml","source_sha256":"7ef2b8359200bba49e112e7e6867a99f1ddfdcf9e60b433f76280bf406db460d","source_url":"https://github.com/anpa1200/sigma/blob/b249e9683190cffdcaf188ccbfb90bf4759844e1/rules/windows/process_creation/proc_creation_win_susp_sysnative.yml","license":"Detection Rule License 1.1","license_url":"https://github.com/SigmaHQ/Detection-Rule-License/blob/main/LICENSE.Detection.Rules.md","yaml":"title: Process Creation Using Sysnative Folder\nid: 3c1b5fb0-c72f-45ba-abd1-4d4c353144ab\nstatus: test\ndescription: Detects process creation events that use the Sysnative folder (common for CobaltStrike spawns)\nreferences:\n    - https://thedfirreport.com/2021/08/29/cobalt-strike-a-defenders-guide/\nauthor: Max Altgelt (Nextron Systems)\ndate: 2022-08-23\nmodified: 2025-10-08\ntags:\n    - attack.privilege-escalation\n    - attack.stealth\n    - attack.t1055\nlogsource:\n    category: process_creation\n    product: windows\ndetection:\n    selection:\n        - CommandLine|contains: ':\\Windows\\Sysnative\\'\n        - Image|contains: ':\\Windows\\Sysnative\\'\n    filter_main_ngen:\n        Image|contains:\n            - 'C:\\Windows\\Microsoft.NET\\Framework64\\v'\n            - 'C:\\Windows\\Microsoft.NET\\Framework\\v'\n            - 'C:\\Windows\\Microsoft.NET\\FrameworkArm\\v'\n            - 'C:\\Windows\\Microsoft.NET\\FrameworkArm64\\v'\n        Image|endswith: '\\ngen.exe'\n        CommandLine|contains: 'install'\n    filter_optional_xampp:\n        CommandLine|contains|all:\n            - '\"C:\\Windows\\sysnative\\cmd.exe\"'\n            - '\\xampp\\'\n            - '\\catalina_start.bat'\n    condition: selection and not 1 of filter_main_* and not 1 of filter_optional_*\nfalsepositives:\n    - Unknown\nlevel: medium\n","validation":"yaml_parsed_not_backend_compiled_or_live_validated","techniques":[{"key":"enterprise/T1055","id":"T1055","name":"Process Injection","page":"techniques/enterprise/T1055/"}],"data_path":"data/detection-rules/3c1b5fb0-c72f-45ba-abd1-4d4c353144ab.json","kind":"sigma"}