Malicious Java Backdoor Execution from Public Documents via javaw (via process_creation)

ATT&CK techniques

C2

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
- T1090Proxy
Exfiltration
Impact

What it detects

This rule detects execution of the MailQueue-Handler Java archive by javaw, a proxy backdoor deployed by the STAC5143 threat cluster after abusing Microsoft Teams to gain remote control. The archive establishes a command and control channel and is staged under a Public Documents MailQueue-Handler directory alongside a bundled Java runtime.

Reporting behind it

Related detections9 linkedT1090 — drag to rearrange

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Malicious Java Backdoor Execution from Public Documents via javaw (via process_creation)

Pivot detection · T1090 · 9 related

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