Malicious Exchange Mailbox Export to ASPX via New-MailboxExportRequest

ATT&CK techniques

Initial Access → Collection

Recon
Resource Dev
Initial Access
- T1190Exploit Public-Facing Application
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
- T1114.002Remote Email Collection
C2
Exfiltration
Impact

What it detects

This rule detects the Exchange management cmdlet New-MailboxExportRequest writing a mailbox export to an .aspx file, the technique used in the DatopLoader ProxyShell chain to drop a web shell onto the Exchange server. Exporting mailbox data to a web-accessible ASPX path is a hallmark of ProxyShell post-exploitation and web shell staging.

Reporting behind it

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Malicious Exchange Mailbox Export to ASPX via New-MailboxExportRequest

Pivot detection · T1190 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

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