SB2025101575 - Improper validation of certificate with host mismatch in FortiOS and FortiProxy
Published: October 15, 2025
Security Bulletin ID
SB2025101575
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Adjecent network
Highest impact
Code execution
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Improper validation of certificate with host mismatch (CVE-ID: CVE-2025-25253)
CWE-ID: CWE-297 - Improper Validation of Certificate with Host Mismatch
CVSSv4: CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Green
The vulnerability allows a remote non-authenticated attacker to execute arbitrary code.
The vulnerability exists due to improper validation of certificate with host mismatch. An unauthenticated attacker in a man-in-the middle position can intercept and tamper with connections to the ZTNA proxy.
Remediation
Install update from vendor's website.