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Fencer Intel
high 8.1

CVE-2026-121528 json

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…

published 13h ago modified 12h ago also EUVD-2026-123907

cvss
8.1
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
—
no EPSS score yet
public exploits
0
none known

Summary

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.

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CVSS scores

assigned by version score vector
CNA 3.1 7.7 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 3.1 8.1 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

  • Fortinet FortiOS

Classification

Weakness
  • CWE-295 Improper Certificate Validation
Technology feeds

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.