CVE-2026-121528
CVE-2026-121528
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.
Fixes and workarounds
Fix
Upgrade to FortiOS version 8.0.0 or above Upgrade to FortiOS version 7.6.5 or above Upgrade to FortiOS version 7.4.10 or above Upgrade to FortiOS version 7.2.14 or above
Source: CNA: fortinetAffected products and versions
| Product | Versions | Authority |
|---|---|---|
| FortiOS Fortinet |
≥ 7.6.0; ≤ 7.6.4 (affected, semver) ≥ 7.4.0; ≤ 7.4.9 (affected, semver) ≥ 7.2.0; ≤ 7.2.13 (affected, semver) ≥ 7.0.0; ≤ 7.0.19 (affected, semver) ≥ 6.4.0; ≤ 6.4.16 (affected, semver) Other versions: unaffected |
CNA: fortinet |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 3.1 / 7.7 high |
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C | CNA: fortinet |
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.
References
- https://fortiguard.fortinet.com/psirt/FG-IR-26-193CNA: fortinet
For agents and automation
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