Detectioncriticaltest
Mailbox Export to Exchange Webserver
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
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Launch
Florian Roth (Nextron Systems), Rich Warren, Christian Burkard (Nextron Systems)Created Mon Aug 09Updated Sun Apr 30516376b4-05cd-4122-bae0-ad7641c38d48windows
Log Source
Windowsmsexchange-management
ProductWindows← raw: windows
Servicemsexchange-management← raw: msexchange-management
Detection Logic
Detection Logic3 selectors
detection:
export_command:
'|all':
- 'New-MailboxExportRequest'
- ' -Mailbox '
export_params:
- '-FilePath "\\\\' # We care about any share location.
- '.aspx'
role_assignment:
'|all':
- 'New-ManagementRoleAssignment'
- ' -Role "Mailbox Import Export"'
- ' -User '
condition: (export_command and export_params) or role_assignmentFalse Positives
Unlikely
False positives are unlikely for most environments. High confidence detection.
References
MITRE ATT&CK
Tactics
Sub-techniques
Rule Metadata
Rule ID
516376b4-05cd-4122-bae0-ad7641c38d48
Status
test
Level
critical
Type
Detection
Created
Mon Aug 09
Modified
Sun Apr 30
Path
rules/windows/builtin/msexchange/win_exchange_proxyshell_mailbox_export.yml
Raw Tags
attack.persistenceattack.t1505.003