CVE-2025-68686: FortiOS symbolic link patch bypass exposes sensitive information

Automated analysis

Generated by VULONE's analysis model from the NVD record, CISA KEV and EPSS data on 17 September 2026. Confidence: high.

high priorityIt is in CISA KEV with a high EPSS percentile, but exploitation requires a prior filesystem-level compromise and the CVSS impact is confidentiality-only (5.9).

What it is

FortiOS contains an information exposure flaw (CWE-200) that lets a remote unauthenticated attacker bypass the patch for the symbolic link persistency mechanism seen in some post-exploit cases, via crafted HTTP requests. It matters because it undermines a defensive fix intended to stop attackers from maintaining a foothold after they have already compromised the device. The record lists affected branches as FortiOS 7.6.0-7.6.1, 7.4.0-7.4.6, and all versions of 7.2, 7.0 and 6.4.

Impact

An attacker who already has filesystem-level access can re-establish symbolic link persistence and read sensitive information despite the vendor patch. The direct gain is information disclosure and persistence, not initial code execution.

Attack surface

Reached remotely over the network through crafted HTTP requests, with no authentication or user interaction required per the CVSS vector (AV:N/PR:N/UI:N). However, the description states the attacker must first have compromised the product via another vulnerability at the filesystem level, so this is a post-compromise step rather than a standalone entry point.

Exploitation

CVE-2025-68686 is listed in CISA KEV (added 2026-07-27, due 2026-08-10), indicating known exploitation, and EPSS shows a 30-day probability of 0.29601 (98th percentile). No ransomware campaign use is documented.

What to do

• Apply the Fortinet FortiOS update that addresses FG-IR-25-934 on all affected branches (7.6, 7.4, 7.2, 7.0, 6.4) per vendor instructions.
• Follow CISA BOD 26-04 guidance, including forensics triage requirements, and discontinue use of the product if mitigations are unavailable.
• Treat any FortiOS device with evidence of prior compromise as untrusted; rebuild rather than relying on the patch alone, since this flaw bypasses the symbolic link persistency fix.
• Restrict management and internet-facing exposure of FortiOS interfaces to reduce the chance of the prerequisite initial compromise.
• Monitor Fortinet PSIRT advisories for updated fixed versions and any revised mitigation guidance.

Detection

• Hunt for crafted HTTP requests targeting FortiOS endpoints that correlate with symbolic link creation or manipulation on the filesystem.
• Audit filesystem and configuration paths on FortiOS devices for unexpected or re-created symbolic links, especially after patching.
• Review logs for prior exploitation of other FortiOS vulnerabilities that would provide the filesystem-level access this flaw requires.
• Alert on anomalous outbound or file-read activity from FortiOS devices consistent with sensitive information exposure.

This assessment is produced automatically and is not human-reviewed. Verify against the vendor advisory before acting on it.