Possible FortiOS Authentication Bypass via local_access_token on WebSocket CLI Endpoint (via webserver)
- Category
- webserver
- Author
- HuntRule
- Published
- 2026-08-05
- Updated
- 2026-08-28
ATT&CK techniques
Initial AccessRecon
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 exploitation of FortiOS and FortiProxy CVE-2024-55591 where an unauthenticated request to the Node.js websocket CLI endpoint supplies a local_access_token to bypass session validation and gain super_admin access. The combination of the ws cli path and the token parameter is not seen in normal administration.
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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