Fortinet FortiOS Sensitive Information Exposure and Symbolic Link Patch Bypass (CVE-2025-68686)

1. Official Firmware Upgrade

Apply the latest firmware updates provided by Fortinet. Refer to the official Fortinet PSIRT advisory FG-IR-25-934 for specific target upgrade versions.

2. Temporary Mitigations & Monitoring

If immediate patching is not feasible, implement the following defensive measures:

• Restrict Management Access: Disable administrative access (HTTPS/HTTP) on external-facing interfaces. Restrict access to trusted administrative IP addresses using Local In Policies.
• Monitor File System Integrity: Audit and monitor the filesystem for unauthorized symbolic link creation or unexpected configuration changes.
• Analyze Web Logs: Inspect HTTP traffic logs for anomalous requests targeting administrative endpoints or post-exploitation patterns.

This vulnerability (CVE-2025-68686) is an Exposure of Sensitive Information to an Unauthorized Actor [CWE-200] in Fortinet FortiOS.

It allows a remote unauthenticated attacker to bypass the security patch previously developed to mitigate the symbolic link persistency mechanism, which is commonly observed in post-exploitation scenarios.

Exploit Mechanics & Prerequisites:

• Prior Compromise Required: To exploit this vulnerability, an attacker must have already compromised the target device at the filesystem level through another vulnerability.
• Bypass via HTTP: Once filesystem access is secured, the attacker can send specially crafted HTTP requests to bypass symbolic link restrictions and access sensitive system information.

Given that this vulnerability is listed in the CISA KEV catalog and has a high EPSS score of 0.94, immediate remediation is highly recommended to prevent active exploitation.