| Name | CVE-2026-4689 |
| Description | Sandbox escape due to incorrect boundary conditions, integer overflow in the XPCOM component. This vulnerability was fixed in Firefox 149, Firefox ESR 115.34, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9. |
| 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-4510-1, DLA-4511-1, DSA-6178-1, DSA-6179-1 |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| firefox (PTS) | sid | 149.0.2-1 | fixed |
| firefox-esr (PTS) | bullseye | 115.14.0esr-1~deb11u1 | vulnerable |
| bullseye (security) | 140.9.1esr-1~deb11u1 | fixed | |
| bookworm | 128.14.0esr-1~deb12u1 | vulnerable | |
| bookworm (security) | 140.9.1esr-1~deb12u1 | fixed | |
| trixie | 140.8.0esr-1~deb13u1 | vulnerable | |
| trixie (security) | 140.9.1esr-1~deb13u1 | fixed | |
| forky, sid | 140.9.1esr-1 | fixed | |
| thunderbird (PTS) | bullseye | 1:115.12.0-1~deb11u1 | vulnerable |
| bullseye (security) | 1:140.9.1esr-1~deb11u1 | fixed | |
| bookworm | 1:140.6.0esr-1~deb12u1 | vulnerable | |
| bookworm (security) | 1:140.9.0esr-1~deb12u1 | fixed | |
| trixie | 1:140.8.0esr-1~deb13u1 | vulnerable | |
| trixie (security) | 1:140.9.0esr-1~deb13u1 | fixed | |
| forky, sid | 1:140.9.0esr-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) | 149.0-1 | |||
| firefox-esr | source | bullseye | 140.9.0esr-1~deb11u1 | DLA-4510-1 | ||
| firefox-esr | source | bookworm | 140.9.0esr-1~deb12u1 | DSA-6178-1 | ||
| firefox-esr | source | trixie | 140.9.0esr-1~deb13u1 | DSA-6178-1 | ||
| firefox-esr | source | (unstable) | 140.9.0esr-1 | |||
| thunderbird | source | bullseye | 1:140.9.0esr-1~deb11u1 | DLA-4511-1 | ||
| thunderbird | source | bookworm | 1:140.9.0esr-1~deb12u1 | DSA-6179-1 | ||
| thunderbird | source | trixie | 1:140.9.0esr-1~deb13u1 | DSA-6179-1 | ||
| thunderbird | source | (unstable) | 1:140.9.0esr-1 |
https://www.mozilla.org/en-US/security/advisories/mfsa2026-20/#CVE-2026-4689
https://www.mozilla.org/en-US/security/advisories/mfsa2026-22/#CVE-2026-4689
https://www.mozilla.org/en-US/security/advisories/mfsa2026-24/#CVE-2026-4689