CVE-2025-0239

Description

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.

Affected Platforms

Weakness Type

CWE-295

References

• https://bugzilla.mozilla.org/show_bug.cgi?id=1929156
• https://www.mozilla.org/security/advisories/mfsa2025-01/
• https://www.mozilla.org/security/advisories/mfsa2025-02/
• https://www.mozilla.org/security/advisories/mfsa2025-04/
• https://www.mozilla.org/security/advisories/mfsa2025-05/
• https://lists.debian.org/debian-lts-announce/2025/01/msg00004.html