CVE-2025-0239
MEDIUM severity · CVSS 4 · CWE-295
4CVSS MEDIUM
Summary
When using Alt-Svc, ALPN did not properly validate certificates when the original server is redirecting to an insecure site. This vulnerability was fixed in Firefox 134, Firefox ESR 128.6, Thunderbird 134, and Thunderbird 128.6.
Impact & exploitability
Attack vectorLocal
Attack complexityLow
Privileges requiredNone
User interactionNone
Confidentiality impactNone
Integrity impactLow
Availability impactNone
Exploit probability (EPSS)0%
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Affected products we track (2)
Recommendation
Apply the vendor fix in your normal patch cycle. Open any affected product above for its exact safe version.
Additional information
- NVD record
- https://www.mozilla.org/security/advisories/mfsa2025-01/Advisory
- https://www.mozilla.org/security/advisories/mfsa2025-02/Advisory
- https://www.mozilla.org/security/advisories/mfsa2025-04/Advisory
- https://www.mozilla.org/security/advisories/mfsa2025-05/Advisory
- https://bugzilla.mozilla.org/show_bug.cgi?id=1929156
- https://lists.debian.org/debian-lts-announce/2025/01/msg00004.html