Malicious ManagementMailboxPicker Webshell Written by Diplomatic Specter

ATT&CK techniques

Persistence

Recon
Resource Dev
Initial Access
Execution
Persistence
- T1505.003Web Shell
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects the creation of the ManagementMailboxPicker.aspx webshell used by the Operation Diplomatic Specter campaign to maintain access to compromised Exchange and web servers. The webshell provides persistent remote command execution and staging for mailbox theft. Detecting its file creation exposes server-side persistence and hands-on access by the espionage actor.

Reporting behind it

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Malicious ManagementMailboxPicker Webshell Written by Diplomatic Specter

Pivot detection · T1505.003 · 9 related

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