FortiOS is a network security platform used by Fortinet to secure networks and protect against cyber threats. This vulnerability allows an unauthenticated attacker to perform a reflected cross-site scripting (XSS) or an open redirect attack via crafted HTTP requests, potentially leading to unauthorized access to sensitive data.
You're affected if you use:
- FortiOS 7.6
- FortiProxy 7.6
- FortiSASE 25.2.a
Check with: grep "FortiOS" /var/log/fortinet.log (Note: This command is specific to FortiGate logs and may not work on other systems.)
This vulnerability is distinct from similar products like Juniper Networks or Cisco Systems, which are also network security platforms but have different architectures.
Upgrade to:
- FortiOS 7.6.4 or above (https://docs.fortinet.com/upgrade-tool)
- FortiProxy 7.6.4 or above (https://docs.fortinet.com/upgrade-tool)
- FortiSASE 25.3.b (no action required, as the issue was remediated in a newer version)
Immediate mitigations:
- Restrict network access to your FortiOS instance (firewall it from the public internet)
- Audit admin account activity for suspicious access patterns
- Monitor for unauthorized token creation