| Name | CVE-2025-6430 |
| Description | When a file download is specified via the `Content-Disposition` header, that directive would be ignored if the file was included via a `<embed>` or `<object>` tag, potentially making a website vulnerable to a cross-site scripting attack. This vulnerability affects Firefox < 140 and Firefox ESR < 128.12. |
| Source | CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
| References | DLA-4231-1, DLA-4239-1, DSA-5950-1, DSA-5959-1 |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| firefox (PTS) | sid | 140.0.4-1 | fixed |
| firefox-esr (PTS) | bullseye | 115.14.0esr-1~deb11u1 | vulnerable |
| bullseye (security) | 128.12.0esr-1~deb11u1 | fixed | |
| bookworm | 128.10.0esr-1~deb12u1 | vulnerable | |
| bookworm (security) | 128.12.0esr-1~deb12u1 | fixed | |
| trixie | 128.11.0esr-1 | vulnerable | |
| sid | 128.12.0esr-1 | fixed | |
| thunderbird (PTS) | bullseye | 1:115.12.0-1~deb11u1 | vulnerable |
| bullseye (security) | 1:128.12.0esr-1~deb11u1 | fixed | |
| bookworm | 1:128.10.0esr-1~deb12u1 | vulnerable | |
| bookworm (security) | 1:128.12.0esr-1~deb12u1 | fixed | |
| trixie, sid | 1:128.12.0esr-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) | 140.0-1 | |||
| firefox-esr | source | bullseye | 128.12.0esr-1~deb11u1 | DLA-4231-1 | ||
| firefox-esr | source | bookworm | 128.12.0esr-1~deb12u1 | DSA-5950-1 | ||
| firefox-esr | source | (unstable) | 128.12.0esr-1 | |||
| thunderbird | source | bullseye | 1:128.12.0esr-1~deb11u1 | DLA-4239-1 | ||
| thunderbird | source | bookworm | 1:128.12.0esr-1~deb12u1 | DSA-5959-1 | ||
| thunderbird | source | (unstable) | 1:128.12.0esr-1 |
https://www.mozilla.org/en-US/security/advisories/mfsa2025-51/#CVE-2025-6430
https://www.mozilla.org/en-US/security/advisories/mfsa2025-53/#CVE-2025-6430
https://www.mozilla.org/en-US/security/advisories/mfsa2025-54/#CVE-2025-6430