| Name | 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 affects Firefox < 134, Firefox ESR < 128.6, Thunderbird < 134, and Thunderbird < 128.6. |
| Source | CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
| References | DLA-4011-1, DLA-4012-1, DSA-5839-1, DSA-5841-1 |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| firefox (PTS) | sid | 144.0-1 | fixed |
| firefox-esr (PTS) | bullseye | 115.14.0esr-1~deb11u1 | vulnerable |
| bullseye (security) | 140.4.0esr-1~deb11u1 | fixed | |
| bookworm | 128.14.0esr-1~deb12u1 | fixed | |
| bookworm (security) | 140.4.0esr-1~deb12u1 | fixed | |
| trixie | 128.14.0esr-1~deb13u1 | fixed | |
| trixie (security) | 140.4.0esr-1~deb13u1 | fixed | |
| forky, sid | 140.4.0esr-1 | fixed | |
| thunderbird (PTS) | bullseye | 1:115.12.0-1~deb11u1 | vulnerable |
| bullseye (security) | 1:140.4.0esr-1~deb11u1 | fixed | |
| bookworm | 1:128.14.0esr-1~deb12u1 | fixed | |
| bookworm (security) | 1:140.3.0esr-1~deb12u1 | fixed | |
| trixie | 1:128.14.0esr-1~deb13u1 | fixed | |
| trixie (security) | 1:140.3.0esr-1~deb13u1 | fixed | |
| forky | 1:140.3.1esr-1 | fixed | |
| sid | 1:140.4.0esr-1 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|---|---|---|---|---|---|
| firefox | source | (unstable) | 134.0-1 | |||
| firefox-esr | source | bullseye | 128.6.0esr-1~deb11u3 | DLA-4011-1 | ||
| firefox-esr | source | bookworm | 128.6.0esr-1~deb12u1 | DSA-5839-1 | ||
| firefox-esr | source | (unstable) | 128.6.0esr-1 | |||
| thunderbird | source | bullseye | 1:128.6.0esr-1~deb11u1 | DLA-4012-1 | ||
| thunderbird | source | bookworm | 1:128.6.0esr-1~deb12u1 | DSA-5841-1 | ||
| thunderbird | source | (unstable) | 1:128.6.0esr-1 |
https://www.mozilla.org/en-US/security/advisories/mfsa2025-01/#CVE-2025-0239
https://www.mozilla.org/en-US/security/advisories/mfsa2025-02/#CVE-2025-0239
https://www.mozilla.org/en-US/security/advisories/mfsa2025-05/#CVE-2025-0239