{"id":"516376b4-05cd-4122-bae0-ad7641c38d48","title":"Mailbox Export to Exchange Webserver","description":"Detects a successful export of an Exchange mailbox to untypical directory or with aspx name suffix which can be used to place a webshell or the needed role assignment for it","author":"Florian Roth (Nextron Systems), Rich Warren, Christian Burkard (Nextron Systems)","status":"test","level":"critical","date":"2021-08-09","modified":"2023-04-30","tags":["attack.persistence","attack.t1505.003"],"technique_ids":["T1505.003"],"logsource":{"service":"msexchange-management","product":"windows"},"falsepositives":["Unlikely"],"references":["https://blog.orange.tw/2021/08/proxylogon-a-new-attack-surface-on-ms-exchange-part-1.html"],"source_path":"rules/windows/builtin/msexchange/win_exchange_proxyshell_mailbox_export.yml","source_sha256":"610c8a02a046035d0303872385ae81283234858effae7b0a563f7e374560f275","source_url":"https://github.com/anpa1200/sigma/blob/b249e9683190cffdcaf188ccbfb90bf4759844e1/rules/windows/builtin/msexchange/win_exchange_proxyshell_mailbox_export.yml","license":"Detection Rule License 1.1","license_url":"https://github.com/SigmaHQ/Detection-Rule-License/blob/main/LICENSE.Detection.Rules.md","yaml":"title: Mailbox Export to Exchange Webserver\nid: 516376b4-05cd-4122-bae0-ad7641c38d48\nstatus: test\ndescription: Detects a successful export of an Exchange mailbox to untypical directory or with aspx name suffix which can be used to place a webshell or the needed role assignment for it\nreferences:\n    - https://blog.orange.tw/2021/08/proxylogon-a-new-attack-surface-on-ms-exchange-part-1.html\nauthor: Florian Roth (Nextron Systems), Rich Warren, Christian Burkard (Nextron Systems)\ndate: 2021-08-09\nmodified: 2023-04-30\ntags:\n    - attack.persistence\n    - attack.t1505.003\nlogsource:\n    service: msexchange-management\n    product: windows\ndetection:\n    export_command:\n        '|all':\n            - 'New-MailboxExportRequest'\n            - ' -Mailbox '\n    export_params:\n        - '-FilePath \"\\\\\\\\' # We care about any share location.\n        - '.aspx'\n    role_assignment:\n        '|all':\n            - 'New-ManagementRoleAssignment'\n            - ' -Role \"Mailbox Import Export\"'\n            - ' -User '\n    condition: (export_command and export_params) or role_assignment\nfalsepositives:\n    - Unlikely\nlevel: critical\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/516376b4-05cd-4122-bae0-ad7641c38d48.json","kind":"sigma"}