FortiOS
CVE-2026-84393: Improper validation of certificate with host mismatch in FortiOS, FortiProxy
A improper validation of certificate with host mismatch vulnerability in Fortinet FortiOS 7.6.1 through 7.6.6, FortiProxy 7.6.2 through 7.6.6 may allow attacker to information disclosure via <insert attack vector here>
Published
ExploitedNot in CISA KEV
Ransomware useNot reportedPer CISA
SeverityHIGHCVSS 3.1 7.3
EPSS0.25%Chance of exploitation in 30 days
Public exploitNot tracked
FixAvailable
Automatic summary from the vendor's CVE record. We haven't written a full analysis of this vulnerability yet.
Affected and fixed versions
| Product / branch | Fixed in |
|---|---|
| FortiOS 7.6.1 to 7.6.6 | 7.6.7 or later |
| FortiProxy 7.6.2 to 7.6.6 | 7.6.7 (upcoming) or later |
Always confirm against the vendor advisory, which lists every fixed hotfix.
What it is
A improper validation of certificate with host mismatch vulnerability in Fortinet FortiOS 7.6.1 through 7.6.6, FortiProxy 7.6.2 through 7.6.6 may allow attacker to information disclosure via <insert attack vector here>
Sources
KEV status, EPSS score and vendor data refreshed automatically, last on 10 Oct 2026.