Open redirect in FortiAuthenticator - CVE-2026-121526
Published: November 11, 2026
Vulnerability identifier: #VU165131
CSH Severity: Medium
CVSS v4: 5.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-121526
CWE-ID: CWE-601
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote non-authenticated attacker to read and manipulate data.
The vulnerability exists due to url redirection to untrusted site ('open redirect') on /login. An unauthenticated attacker can perform an open redirect attack via crafted HTTP requests.
Affected software
FortiAuthenticator
How to mitigate CVE-2026-121526
Install update from vendor's website.
FortiAuthenticator - addressed in versions 6.6.11, 8.0.4