CVE-2025-6433Critical· 9.8▾ MidnightIf 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 req…
▾ Midnight zone — Critical, or high with PoC / in-the-wild
impact 53.9 · likelihood 0.1 · exploitation 0
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Exploit-prediction probability, daily snapshots since Sep 30.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
Last analysed / modified upstream
0.3%
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.
firefox < 140.0Upgrade past the affected range:
firefox 140.0Connected by shared product, vendor, weakness, or advisory.
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CVE-2025-0239Medium· 4.0When using Alt-Svc, ALPN did not properly validate certificates when the original server is redirecting to an insecure site
CVE-2026-118008High· 8.8Privilege escalation in the DOM: Navigation component
CVE-2026-117999NoneRace condition in the IPC component
CVE-2026-117976NoneSite isolation issue in the DOM: Navigation component
CVE-2026-118027NoneFrame poisoning in the Layout component