CVE-2026-21743 Missing authorization in FortiAuthenticator

What is CVE-2026-21743?

CVE-2026-21743 is a medium-severity missing authorization vulnerability in Fortinet FortiAuthenticator, published on 10 Feb 2026. An attacker needs administrator access to exploit it, with no action from the victim.

Official description

A missing authorization vulnerability in Fortinet FortiAuthenticator 6.6.0 through 6.6.6, FortiAuthenticator 6.5 all versions, FortiAuthenticator 6.4 all versions, FortiAuthenticator 6.3 all versions may allow a read-only user to make modification to local users via a file upload to an unprotected endpoint.

Weakness: CWE-862

Which versions are affected by CVE-2026-21743?

It affects 1 product.

Products include Fortinet Fortiauthenticator.

How do I fix CVE-2026-21743?

No fix has been published for CVE-2026-21743 yet. Limit exposure of the affected software until one is available.

Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.

Is CVE-2026-21743 being exploited?

There is no known exploitation of CVE-2026-21743 in the wild and no public exploit code.

Other vulnerabilities in Fortinet FortiAuthenticator

• CVE-2026-44277 Missing authorization in FortiAuthenticator Critical 9.1
• CVE-2013-6990 Privilege escalation in n/a Critical 9.0
• CVE-2021-43067 Information disclosure in Fortinet FortiAuthenticator High 8.3
• CVE-2021-22124 Denial of service in Fortinet FortiSandbox, FortiAuthenticator High 7.5
• CVE-2015-1455 Hardcoded credentials in n/a High 7.5

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-73jp-396j-hc6q.