{"id":"13e6fe51-d478-4c7e-b0f2-6da9b400a829","title":"Suspicious File Downloaded From Direct IP Via Certutil.EXE","description":"Detects the execution of certutil with certain flags that allow the utility to download files from direct IPs.","author":"Nasreddine Bencherchali (Nextron Systems)","status":"test","level":"high","date":"2023-02-15","modified":"2025-12-01","tags":["attack.stealth","attack.t1027","attack.command-and-control","attack.t1105"],"technique_ids":["T1027","T1105"],"logsource":{"category":"process_creation","product":"windows"},"falsepositives":["Unknown"],"references":["https://learn.microsoft.com/en-us/windows-server/administration/windows-commands/certutil","https://forensicitguy.github.io/agenttesla-vba-certutil-download/","https://news.sophos.com/en-us/2021/04/13/compromised-exchange-server-hosting-cryptojacker-targeting-other-exchange-servers/","https://twitter.com/egre55/status/1087685529016193025","https://lolbas-project.github.io/lolbas/Binaries/Certutil/","https://twitter.com/_JohnHammond/status/1708910264261980634","https://www.hexacorn.com/blog/2020/08/23/certutil-one-more-gui-lolbin"],"source_path":"rules/windows/process_creation/proc_creation_win_certutil_download_direct_ip.yml","source_sha256":"e541e6f3383f9ab530f44b20dcee5046be96410ab9a48d78d3437ec85ea48fa0","source_url":"https://github.com/anpa1200/sigma/blob/b249e9683190cffdcaf188ccbfb90bf4759844e1/rules/windows/process_creation/proc_creation_win_certutil_download_direct_ip.yml","license":"Detection Rule License 1.1","license_url":"https://github.com/SigmaHQ/Detection-Rule-License/blob/main/LICENSE.Detection.Rules.md","yaml":"title: Suspicious File Downloaded From Direct IP Via Certutil.EXE\nid: 13e6fe51-d478-4c7e-b0f2-6da9b400a829\nrelated:\n    - id: 19b08b1c-861d-4e75-a1ef-ea0c1baf202b # Direct IP download\n      type: similar\n    - id: 42a5f1e7-9603-4f6d-97ae-3f37d130d794 # File sharing download\n      type: similar\nstatus: test\ndescription: Detects the execution of certutil with certain flags that allow the utility to download files from direct IPs.\nreferences:\n    - https://learn.microsoft.com/en-us/windows-server/administration/windows-commands/certutil\n    - https://forensicitguy.github.io/agenttesla-vba-certutil-download/\n    - https://news.sophos.com/en-us/2021/04/13/compromised-exchange-server-hosting-cryptojacker-targeting-other-exchange-servers/\n    - https://twitter.com/egre55/status/1087685529016193025\n    - https://lolbas-project.github.io/lolbas/Binaries/Certutil/\n    - https://twitter.com/_JohnHammond/status/1708910264261980634\n    - https://www.hexacorn.com/blog/2020/08/23/certutil-one-more-gui-lolbin\nauthor: Nasreddine Bencherchali (Nextron Systems)\ndate: 2023-02-15\nmodified: 2025-12-01\ntags:\n    - attack.stealth\n    - attack.t1027\n    - attack.command-and-control\n    - attack.t1105\nlogsource:\n    category: process_creation\n    product: windows\ndetection:\n    selection_img:\n        - Image|endswith: '\\certutil.exe'\n        - OriginalFileName: 'CertUtil.exe'\n    selection_flags:\n        CommandLine|contains:\n            - 'urlcache '\n            - 'verifyctl '\n            - 'URL '\n    selection_http:\n        CommandLine|contains:\n            - '://1'\n            - '://2'\n            - '://3'\n            - '://4'\n            - '://5'\n            - '://6'\n            - '://7'\n            - '://8'\n            - '://9'\n    # filter_local_ips:\n    #     # Note: Uncomment this filter if you want to exclude local IPs\n    #     CommandLine|contains:\n    #         - '://10.' # 10.0.0.0/8\n    #         - '://192.168.' # 192.168.0.0/16\n    #         - '://172.16.' # 172.16.0.0/12\n    #         - '://172.17.'\n    #         - '://172.18.'\n    #         - '://172.19.'\n    #         - '://172.20.'\n    #         - '://172.21.'\n    #         - '://172.22.'\n    #         - '://172.23.'\n    #         - '://172.24.'\n    #         - '://172.25.'\n    #         - '://172.26.'\n    #         - '://172.27.'\n    #         - '://172.28.'\n    #         - '://172.29.'\n    #         - '://172.30.'\n    #         - '://172.31.'\n    #         - '://127.' # 127.0.0.0/8\n    #         - '://169.254.' # 169.254.0.0/16\n    filter_main_seven_zip:\n        CommandLine|contains: '://7-' # For https://7-zip.org/\n    condition: all of selection_* and not 1 of filter_main_*\nfalsepositives:\n    - Unknown\nlevel: high\nregression_tests_path: regression_data/rules/windows/process_creation/proc_creation_win_certutil_download_direct_ip/info.yml\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/T1105","id":"T1105","name":"Ingress Tool Transfer","page":"techniques/enterprise/T1105/"}],"data_path":"data/detection-rules/13e6fe51-d478-4c7e-b0f2-6da9b400a829.json","kind":"sigma"}