{"id":"efafe0bf-4238-479e-af8f-797bd3490d2d","title":"Outbound Network Connection Initiated By Cmstp.EXE","description":"Detects a network connection initiated by Cmstp.EXE\nIts uncommon for \"cmstp.exe\" to initiate an outbound network connection. Investigate the source of such requests to determine if they are malicious.\n","author":"Nasreddine Bencherchali (Nextron Systems)","status":"test","level":"high","date":"2022-08-30","modified":"2024-05-31","tags":["attack.stealth","attack.t1218.003"],"technique_ids":["T1218.003"],"logsource":{"category":"network_connection","product":"windows"},"falsepositives":["Unknown"],"references":["https://web.archive.org/web/20190720093911/http://www.endurant.io/cmstp/detecting-cmstp-enabled-code-execution-and-uac-bypass-with-sysmon/"],"source_path":"rules/windows/network_connection/net_connection_win_cmstp_initiated_connection.yml","source_sha256":"2f068a8fa0a2c7d1f94ef7e9fc3c7ea71369330d986910f5746956c41b27a62f","source_url":"https://github.com/anpa1200/sigma/blob/b249e9683190cffdcaf188ccbfb90bf4759844e1/rules/windows/network_connection/net_connection_win_cmstp_initiated_connection.yml","license":"Detection Rule License 1.1","license_url":"https://github.com/SigmaHQ/Detection-Rule-License/blob/main/LICENSE.Detection.Rules.md","yaml":"title: Outbound Network Connection Initiated By Cmstp.EXE\nid: efafe0bf-4238-479e-af8f-797bd3490d2d\nstatus: test\ndescription: |\n    Detects a network connection initiated by Cmstp.EXE\n    Its uncommon for \"cmstp.exe\" to initiate an outbound network connection. Investigate the source of such requests to determine if they are malicious.\nreferences:\n    - https://web.archive.org/web/20190720093911/http://www.endurant.io/cmstp/detecting-cmstp-enabled-code-execution-and-uac-bypass-with-sysmon/\nauthor: Nasreddine Bencherchali (Nextron Systems)\ndate: 2022-08-30\nmodified: 2024-05-31\ntags:\n    - attack.stealth\n    - attack.t1218.003\nlogsource:\n    category: network_connection\n    product: windows\ndetection:\n    selection:\n        Image|endswith: '\\cmstp.exe'\n        Initiated: 'true'\n    filter_main_local_ranges:\n        DestinationIp|cidr:\n            - '127.0.0.0/8'\n            - '10.0.0.0/8'\n            - '172.16.0.0/12'\n            - '192.168.0.0/16'\n            - '169.254.0.0/16'\n            - '::1/128'  # IPv6 loopback\n            - 'fe80::/10'  # IPv6 link-local addresses\n            - 'fc00::/7'  # IPv6 private addresses\n    condition: selection and not 1 of filter_main_*\nfalsepositives:\n    - Unknown\n# Note: Please report any false positive seen in the wild to help tune the rule.\nlevel: high\n","validation":"yaml_parsed_not_backend_compiled_or_live_validated","techniques":[{"key":"enterprise/T1218.003","id":"T1218.003","name":"CMSTP","page":"techniques/enterprise/T1218.003/"}],"data_path":"data/detection-rules/efafe0bf-4238-479e-af8f-797bd3490d2d.json","kind":"sigma"}