CVE-2026-84393: Information disclosure in Fortinet FortiOS
CVE-2026-84393 is a high-severity vulnerability in Fortinet FortiOS and FortiProxy involving improper validation of certificates with host mismatches. This flaw affects FortiOS versions 7.6.1 through 7.6.6 and FortiProxy versions 7.6.2 through 7.6.6. Successful exploitation could lead to information disclosure. An official fix is available to address this issue.
AI Analysis
Technical Summary
This vulnerability in Fortinet FortiOS and FortiProxy arises from improper validation of certificates when there is a host mismatch. It affects FortiOS versions 7.6.1 through 7.6.6 and FortiProxy versions 7.6.2 through 7.6.6. The flaw may allow an attacker to disclose sensitive information. The CVSS 3.1 base score is 7.3, indicating high severity, with network attack vector, high attack complexity, no privileges or user interaction required, and impacts confidentiality, integrity, and availability. An official fix has been released by Fortinet to remediate this vulnerability.
Potential Impact
Exploitation of this vulnerability could lead to disclosure of sensitive information due to improper certificate validation. The high CVSS score reflects significant impact on confidentiality, integrity, and availability. However, no known exploits are reported in the wild at this time.
Mitigation Recommendations
An official fix is available from Fortinet for affected versions. Users should apply the vendor-provided patches promptly to remediate this vulnerability. Since the remediation level is official-fix, updating to fixed versions is the recommended mitigation.
CVE-2026-84393: Information disclosure in Fortinet FortiOS
Description
CVE-2026-84393 is a high-severity vulnerability in Fortinet FortiOS and FortiProxy involving improper validation of certificates with host mismatches. This flaw affects FortiOS versions 7.6.1 through 7.6.6 and FortiProxy versions 7.6.2 through 7.6.6. Successful exploitation could lead to information disclosure. An official fix is available to address this issue.
CVSS v3.1
Score 7.3high
Affected software
cpe:2.3:a:fortinet:fortiproxy:7.6.6:*:*:*:*:*:*:*cpe:2.3:a:fortinet:fortiproxy:7.6.5:*:*:*:*:*:*:*cpe:2.3:a:fortinet:fortiproxy:7.6.4:*:*:*:*:*:*:*cpe:2.3:a:fortinet:fortiproxy:7.6.3:*:*:*:*:*:*:*cpe:2.3:a:fortinet:fortiproxy:7.6.2:*:*:*:*:*:*:*AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability in Fortinet FortiOS and FortiProxy arises from improper validation of certificates when there is a host mismatch. It affects FortiOS versions 7.6.1 through 7.6.6 and FortiProxy versions 7.6.2 through 7.6.6. The flaw may allow an attacker to disclose sensitive information. The CVSS 3.1 base score is 7.3, indicating high severity, with network attack vector, high attack complexity, no privileges or user interaction required, and impacts confidentiality, integrity, and availability. An official fix has been released by Fortinet to remediate this vulnerability.
Potential Impact
Exploitation of this vulnerability could lead to disclosure of sensitive information due to improper certificate validation. The high CVSS score reflects significant impact on confidentiality, integrity, and availability. However, no known exploits are reported in the wild at this time.
Mitigation Recommendations
An official fix is available from Fortinet for affected versions. Users should apply the vendor-provided patches promptly to remediate this vulnerability. Since the remediation level is official-fix, updating to fixed versions is the recommended mitigation.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- fortinet
- Date Reserved
- 2026-09-01T16:36:14.802Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
Threat ID: 6aa03d6cacd9273b49f0b442
Added to database: 09/08/2026, 16:53:00 UTC
Last enriched: 09/08/2026, 17:07:05 UTC
Last updated: 09/08/2026, 17:28:39 UTC
Views: 6
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