Quick answers
- Is CVE-2026-84393 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-84393 being exploited in the wild.
- How severe is CVE-2026-84393?
- High severity, with a CVSS score of 8.1, published 8 September 2026.
- Which products and versions are affected?
- Fortinet FortiOS 7.6.1 through 7.6.6; Fortinet FortiProxy 7.6.2 through 7.6.6.
- Is there a fix for CVE-2026-84393?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-84393 attacked?
- It is attacked over the network.
- Am I affected by CVE-2026-84393?
- Check whether you run Fortinet FortiOS or Fortinet FortiProxy at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
This vulnerability is a certificate validation flaw (CWE-295) in the ZTNA portal component that fails to properly validate SSL/TLS certificates against the target hostname. The flaw allows remote, unauthenticated attackers to perform Man-in-the-Middle (MITM) attacks on the communication channel between the ZTNA portal and backend destination websites. No authentication is required; the attack is network-accessible. The vulnerability affects FortiOS 7.6.1–7.6.6 and FortiProxy 7.6.2–7.6.6. Patches are available: upgrade to FortiOS 7.6.7 or FortiProxy 7.6.7 and above.
Affected products
- Fortinet FortiOS 7.6.1 through 7.6.6
- Fortinet FortiProxy 7.6.2 through 7.6.6
Timeline
- 2026-09-08: disclosed: Initial publication by Fortinet PSIRT