| Name | CVE-2026-109708 |
| Description | Sandbox escape due to incorrect boundary conditions in the Networking component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, Thunderbird 153.5, and Firefox ESR 115.44. |
| 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-4836-1, DLA-4863-1, DSA-6560-1, DSA-6585-1 |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| firefox (PTS) | sid | 159.0-1 | fixed |
| firefox-esr (PTS) | bookworm | 140.12.0esr-1~deb12u1 | vulnerable |
| bookworm (security) | 153.6.0esr-1~deb12u2 | fixed | |
| trixie | 140.15.0esr-1~deb13u1 | vulnerable | |
| trixie (security) | 153.6.0esr-1~deb13u1 | fixed | |
| forky | 153.5.1esr-1 | fixed | |
| sid | 153.6.0esr-1 | fixed | |
| thunderbird (PTS) | bookworm | 1:140.12.0esr-1~deb12u1 | vulnerable |
| bookworm (security) | 1:153.6.0esr-1~deb12u2 | fixed | |
| trixie | 1:140.12.0esr-1~deb13u1 | vulnerable | |
| trixie (security) | 1:153.6.0esr-1~deb13u1 | fixed | |
| forky | 1:153.5.0esr-1 | fixed | |
| sid | 1:153.6.0esr-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) | 158.0-1 | |||
| firefox-esr | source | bookworm | 153.5.0esr-1~deb12u1 | DLA-4836-1 | ||
| firefox-esr | source | trixie | 153.5.0esr-1~deb13u1 | DSA-6560-1 | ||
| firefox-esr | source | (unstable) | 153.5.0esr-1 | |||
| thunderbird | source | bookworm | 1:153.5.1esr-1~deb12u1 | DLA-4863-1 | ||
| thunderbird | source | trixie | 1:153.5.1esr-1~deb13u1 | DSA-6585-1 | ||
| thunderbird | source | (unstable) | 1:153.5.0esr-1 |
https://www.mozilla.org/en-US/security/advisories/mfsa2026-106/#CVE-2026-109708
https://www.mozilla.org/en-US/security/advisories/mfsa2026-108/#CVE-2026-109708
https://www.mozilla.org/en-US/security/advisories/mfsa2026-109/#CVE-2026-109708