Missing authentication for critical function in FortiOS - CVE-2026-126259
Published: November 11, 2026
Vulnerability identifier: #VU165129
CSH Severity: High
CVSS v4: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-126259
CWE-ID: CWE-306
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote non-authenticated attacker to execute arbitrary code.
The vulnerability exists due to missing authentication for critical function via HA. An unauthenticated attacker with ha fgsp + standalone-config-sync, or autoscale can execute command as super admin via crafted HA packets.
Affected software
FortiOS
How to mitigate CVE-2026-126259
Install update from vendor's website.
FortiOS - addressed in versions 7.2.14, 7.4.13, 7.6.8, 8.0.1