vulnerability
Ubuntu: USN-7991-1 (CVE-2025-6433): Thunderbird vulnerabilities
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 10 | (AV:N/AC:L/Au:N/C:C/I:C/A:C) | Jun 24, 2025 | Jun 26, 2025 | Feb 4, 2026 |
Severity
10
CVSS
(AV:N/AC:L/Au:N/C:C/I:C/A:C)
Published
Jun 24, 2025
Added
Jun 26, 2025
Modified
Feb 4, 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 affects Firefox < 140 and Thunderbird < 140.
Solution
ubuntu-upgrade-thunderbird
References
- CVE-2025-6433
- https://attackerkb.com/topics/CVE-2025-6433
- CWE-295
- UBUNTU-USN-7991-1
- URL-https://bugzilla.mozilla.org/show_bug.cgi?id=1954033
- URL-https://www.cve.org/CVERecord?id=CVE-2025-6433
- URL-https://www.mozilla.org/en-US/security/advisories/mfsa2025-51/#CVE-2025-6433
- URL-https://www.mozilla.org/security/advisories/mfsa2025-51/
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