| Name | CVE-2026-100819 |
| Description | Sandbox escape due to incorrect boundary conditions in the XPCOM component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. |
| 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-4810-1, DLA-4814-1, DSA-6533-1, DSA-6536-1 |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| firefox (PTS) | sid | 157.0-1 | fixed |
| firefox-esr (PTS) | bookworm | 140.12.0esr-1~deb12u1 | vulnerable |
| bookworm (security) | 153.4.0esr-1~deb12u1 | fixed | |
| trixie | 140.15.0esr-1~deb13u1 | vulnerable | |
| trixie (security) | 153.4.0esr-1~deb13u1 | fixed | |
| forky | 140.16.0esr-1 | vulnerable | |
| sid | 153.4.0esr-1 | fixed | |
| thunderbird (PTS) | bookworm | 1:140.12.0esr-1~deb12u1 | vulnerable |
| bookworm (security) | 1:140.17.0esr-1~deb12u1 | fixed | |
| trixie | 1:140.12.0esr-1~deb13u1 | vulnerable | |
| trixie (security) | 1:140.17.0esr-1~deb13u1 | fixed | |
| forky | 1:140.14.0esr-1 | vulnerable | |
| sid | 1:153.4.0esr-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) | 157.0-1 | |||
| firefox-esr | source | bookworm | 153.4.0esr-1~deb12u1 | DLA-4814-1 | ||
| firefox-esr | source | trixie | 153.4.0esr-1~deb13u1 | DSA-6533-1 | ||
| firefox-esr | source | (unstable) | 153.4.0esr-1 | |||
| thunderbird | source | bookworm | 1:140.17.0esr-1~deb12u1 | DLA-4810-1 | ||
| thunderbird | source | trixie | 1:140.17.0esr-1~deb13u1 | DSA-6536-1 | ||
| thunderbird | source | (unstable) | 1:153.4.0esr-1 |
https://www.mozilla.org/en-US/security/advisories/mfsa2026-97/#CVE-2026-100819
https://www.mozilla.org/en-US/security/advisories/mfsa2026-100/#CVE-2026-100819
https://www.mozilla.org/en-US/security/advisories/mfsa2026-103/#CVE-2026-100819