{"id":"bd1212e5-78da-431e-95fa-c58e3237a8e6","title":"Suspicious ASPX File Drop by Exchange","description":"Detects suspicious file type dropped by an Exchange component in IIS into a suspicious folder","author":"Florian Roth (Nextron Systems), MSTI (query, idea)","status":"test","level":"high","date":"2022-10-01","modified":"","tags":["attack.persistence","attack.t1505.003"],"technique_ids":["T1505.003"],"logsource":{"product":"windows","category":"file_event"},"falsepositives":["Unknown"],"references":["https://www.microsoft.com/security/blog/2022/09/30/analyzing-attacks-using-the-exchange-vulnerabilities-cve-2022-41040-and-cve-2022-41082/","https://www.gteltsc.vn/blog/canh-bao-chien-dich-tan-cong-su-dung-lo-hong-zero-day-tren-microsoft-exchange-server-12714.html","https://en.gteltsc.vn/blog/cap-nhat-nhe-ve-lo-hong-bao-mat-0day-microsoft-exchange-dang-duoc-su-dung-de-tan-cong-cac-to-chuc-tai-viet-nam-9685.html"],"source_path":"rules/windows/file/file_event/file_event_win_exchange_webshell_drop.yml","source_sha256":"6d0f05735186cd90ade6c6d33a677c66582a1d593df11abd551cb604b9acf1fc","source_url":"https://github.com/anpa1200/sigma/blob/b249e9683190cffdcaf188ccbfb90bf4759844e1/rules/windows/file/file_event/file_event_win_exchange_webshell_drop.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 ASPX File Drop by Exchange\nid: bd1212e5-78da-431e-95fa-c58e3237a8e6\nrelated:\n    - id: 6b269392-9eba-40b5-acb6-55c882b20ba6\n      type: similar\nstatus: test\ndescription: Detects suspicious file type dropped by an Exchange component in IIS into a suspicious folder\nreferences:\n    - https://www.microsoft.com/security/blog/2022/09/30/analyzing-attacks-using-the-exchange-vulnerabilities-cve-2022-41040-and-cve-2022-41082/\n    - https://www.gteltsc.vn/blog/canh-bao-chien-dich-tan-cong-su-dung-lo-hong-zero-day-tren-microsoft-exchange-server-12714.html\n    - https://en.gteltsc.vn/blog/cap-nhat-nhe-ve-lo-hong-bao-mat-0day-microsoft-exchange-dang-duoc-su-dung-de-tan-cong-cac-to-chuc-tai-viet-nam-9685.html\nauthor: Florian Roth (Nextron Systems), MSTI (query, idea)\ndate: 2022-10-01\ntags:\n    - attack.persistence\n    - attack.t1505.003\nlogsource:\n    product: windows\n    category: file_event\ndetection:\n    selection:\n        Image|endswith: '\\w3wp.exe'\n        CommandLine|contains: 'MSExchange'\n        TargetFilename|contains:\n            - 'FrontEnd\\HttpProxy\\'           # from GTSC and MSTI reports\n            - '\\inetpub\\wwwroot\\aspnet_client\\' # from GTSC report\n    selection_types:\n        TargetFilename|endswith:\n            - '.aspx'\n            - '.asp'\n            - '.ashx'\n    condition: all of selection*\nfalsepositives:\n    - Unknown\nlevel: high\n","validation":"yaml_parsed_not_backend_compiled_or_live_validated","techniques":[{"key":"enterprise/T1505.003","id":"T1505.003","name":"Web Shell","page":"techniques/enterprise/T1505.003/"}],"data_path":"data/detection-rules/bd1212e5-78da-431e-95fa-c58e3237a8e6.json","kind":"sigma"}