Authorization bypass through user-controlled key in FortiMail - CVE-2026-126156
Published: November 11, 2026
Vulnerability identifier: #VU165264
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:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-126156
CWE-ID: CWE-639
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 authorization bypass through user-controlled key. An unauthenticated remote attacker can take over an arbitrary IBE recipient account via crafted HTTP requests.
Affected software
FortiMail
How to mitigate CVE-2026-126156
Install update from vendor's website.
FortiMail - addressed in versions 7.4.9, 7.6.7, 8.0.2