Suspicious MDaemon WorldClient CgiBase6 Extension Registration by Careto

ATT&CK techniques

Persistence → Priv Esc

Recon
Resource Dev
Initial Access
Execution
Persistence
- T1546.015Component Object Model Hijacking
Priv Esc
- T1546.015Component Object Model Hijacking
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects modification of the MDaemon WorldClient.ini configuration to add CgiBase6 or CgiFile6 CGI extension entries. The Careto APT abuses this legitimate mail server extension mechanism to load a server-side implant that executes attacker CGI code. Injection of these CGI keys into the WorldClient configuration indicates a persistent web-facing backdoor.

Reporting behind it

Related detections9 linkedT1546.015 — drag to rearrange

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Suspicious MDaemon WorldClient CgiBase6 Extension Registration by Careto

Pivot detection · T1546.015 · 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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