vulnerability
MFSA2025-54 Thunderbird: Security Vulnerabilities fixed in Thunderbird 140 (CVE-2025-6433)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 10 | (AV:N/AC:L/Au:N/C:C/I:C/A:C) | Jun 24, 2025 | Jul 3, 2025 | Apr 15, 2026 |
Severity
10
CVSS
(AV:N/AC:L/Au:N/C:C/I:C/A:C)
Published
Jun 24, 2025
Added
Jul 3, 2025
Modified
Apr 15, 2026
Description
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.
Solution
mozilla-thunderbird-upgrade-140_0
Rapid7 Labs
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