Product:
FortiOS
Summary
An inconsistent interpretation of http requests vulnerability in Fortinet FortiOS may allow an unauthenticated attacker to smuggle an unlogged http request through the firewall policies via a specially crafted header. This issue affects multiple versions of FortiOS, potentially exposing systems to unauthorized access. The vulnerability is categorized as a medium severity issue.
Details
| Severity | Base Score | CVE |
|---|---|---|
| MEDIUM | 5.8 | CVE-2025-55018 |
Exploitation
To exploit this vulnerability, an attacker can craft a specially formatted HTTP request that takes advantage of the inconsistent handling of requests by the FortiOS firewall. By sending this request, the attacker can bypass security measures and potentially gain unauthorized access to the network. The attack does not require any authentication or user interaction, making it easier for malicious actors to execute.
Affected Products
- FortiOS 7.6.0: Latest version affected by the vulnerability.
- FortiOS 7.4.0 through 7.4.9: Multiple versions within this range are vulnerable.
- FortiOS 7.2: All versions are affected.
- FortiOS 7.0: All versions are affected.
- FortiOS 6.4.3 through 6.4.16: Multiple versions within this range are vulnerable.
Mitigation
To mitigate this vulnerability, it is recommended that users upgrade to the latest version of FortiOS that addresses this issue. Additionally, implementing strict firewall rules and monitoring HTTP traffic for unusual patterns can help reduce the risk of exploitation. Regularly reviewing and updating security policies is also advised.