High severity · published Sep 8, 2026
CVE-2026-84393
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…
8.1
CVSS
0.3%
EPSS
No
On KEV
Description
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>
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 20% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FO
FortiOS · Fortinet
7.6.1 through 7.6.6 · source: vendor
FO
FortiProxy · Fortinet
7.6.2 through 7.6.6 · source: vendor
RA
RUGGEDCOM APE1808 · Siemens
0 · source: CISA
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-84393
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-84393
fortiguard.fortinet.com
https://fortiguard.fortinet.com/psirt/FG-IR-26-174
cert-portal.siemens.com
https://cert-portal.siemens.com/productcert/html/ssa-127084.html
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