CVE-2026-84393: Fortinet ZTNA Portal Improper Certificate Validation
This Fortinet advisory covers CVE-2026-84393 in FortiOS and FortiProxy.
Key facts
- Vendor rating
- High, CVSS 8.1
- CISA KEV
- Not listed (catalogue checked )
- Affected
- FortiOS FortiOS: 7.2 through 8.0 (vendor-listed versions); FortiProxy FortiProxy: 7.2 through 8.0 (vendor-listed versions)
- Advisory id
- FG-IR-26-174
- Source published
- Source revised
- Listed by VulniPulse
Compiled by VulniPulse from the linked sources. How records are collected and checked.
Affected products & platforms
Description
CVSSv3 Score:
8.1
An improper certificate validation vulnerability [CWE-295] in FortiOS and FortiProxy Agentless ZTNA portal may allow a remote and unauthenticated attacker to perform a Man-in-the-Middle attack on the communication channel between the ZTNA portal and the backend destination website.
Revised on 2026-09-08 00:00:00
Text from the source record.
- FortiOS FortiOS: 7.2 through 8.0 (vendor-listed versions)
- FortiProxy FortiProxy: 7.2 through 8.0 (vendor-listed versions)
Official advisory · high-confidence parse· fetched ·verify at source
End-of-life dates for Fortinet FortiOS
CVE-2026-84393 in other vendors' advisories
- Fortinet: CVE-2026-84393, high severity
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