Malicious UNC4841 FOXDOOR Shell Execution from Non-Standard Path (via process_creation)
- Product
- linux
- Category
- process_creation
- Author
- HuntRule
- Published
- 2026-06-12
- Updated
- 2026-08-28
ATT&CK techniques
PersistenceRecon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact
What it detects
This rule detects execution of the FOXDOOR shell component from the hardcoded /usr/share/foxdoor/ directory used by UNC4841 on compromised Barracuda ESG appliances. The path and binary name are attacker-controlled artifacts that provide interactive backdoor access. Detecting execution from this planted directory reveals active hands-on-keyboard operation on the appliance.
Reporting behind it
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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