Improper verification of source of a communication channel in FortiOS - CVE-2025-62439
Published: February 10, 2026
Vulnerability identifier: #VU122535
CSH Severity: Low
CVSS v4: 2.3 [CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N]
CVE-ID: CVE-2025-62439
CWE-ID: CWE-940
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to gain unauthorized access to protected network.
The vulnerability exists due to firewall policy bypass in FSSO Terminal Services Agent. A remote authenticated user with knowledge of FSSO policy configurations can gain unauthorized access to protected network resources via crafted requests.
Affected software
FortiOS
How to mitigate CVE-2025-62439
The vulnerability is resolved with the latest version of ForiOS with FSSO TS Agent version 5.0 build 0324 and later.
FortiOS - addressed in versions 7.4.10, 7.6.5