Improper Certificate Validation in Fortinet FortiOS

Publication date: 2026-11-11

Last updated on: 2026-11-11

Assigner: Fortinet, Inc.

Description

A improper certificate validation vulnerability in Fortinet FortiOS 7.6.0 through 7.6.4, FortiOS 7.4.0 through 7.4.9, FortiOS 7.2.0 through 7.2.13 may allow a remote and unauthenticated attacker to perform a Man-in-the-Middle attack on the communication channel between the SSLVPN web portal and the backend destination website.

CVSS Scores

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Meta Information

Published

2026-11-11

Last Modified

2026-11-11

Generated

2026-11-12

EPSS Evaluated

N/A

NVD

CVE-2026-121528

EUVD

EUVD-2026-123907

Affected Vendors & Products

Vendor	Product	Version / Range
Fortinet	FortiOS	From 7.6.0 (inc) to 7.6.4 (inc)
Fortinet	FortiOS	From 7.4.0 (inc) to 7.4.9 (inc)
Fortinet	FortiOS	From 7.2.0 (inc) to 7.2.13 (inc)
Fortinet	FortiOS	From 7.0.0 (inc) to 7.0.19 (inc)
Fortinet	FortiOS	From 6.4.0 (inc) to 6.4.16 (inc)

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-295	The product does not validate, or incorrectly validates, a certificate.

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