cvedb.io
CVE-2025-6433
CRITICAL · CVSS 9.8
EPSS exploitation probability: 0%
Published 2025-06-24T13:15:24.327 · Last modified 2026-06-17T10:01:53.090

Summary

If a user visited a webpage with an invalid TLS certificate, and granted an exception, the webpage was able to provide a WebAuthn challenge that the user would be prompted to complete. This is in violation of the WebAuthN spec which requires "a secure transport established without errors". This vulnerability was fixed in Firefox 140 and Thunderbird 140.

Affected products

mozilla — firefox

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.