Suspicious FortiGate Local VPN Certificate Generation (via fortigate)

ATT&CK techniques

Persistence → Cred Access

Recon
Resource Dev
Initial Access
Execution
Persistence
- T1556Modify Authentication Process
Priv Esc
Defense Evasion
- T1556Modify Authentication Process
Cred Access
- T1556Modify Authentication Process
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects the FortiGate CLI command that generates a local RSA VPN certificate on the appliance. Threat actors abused this to mint certificates that support covert VPN or tunneling access after compromise. Unexpected certificate generation on a firewall is a sign of authentication tampering and access maintenance.

Reporting behind it

Related detections9 linkedT1556 — drag to rearrange

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Suspicious FortiGate Local VPN Certificate Generation (via fortigate)

Pivot detection · T1556 · 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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