| Name | CVE-2026-75874 |
| Description | Sandbox escape in the Remote Settings Client component. This vulnerability was fixed in Firefox 154, Thunderbird 154, Firefox ESR 115.40, Firefox ESR 140.15, Firefox ESR 153.2, Thunderbird 140.15, and Thunderbird 153.2. |
| 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 | DSA-6481-1 |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| firefox (PTS) | sid | 155.0-1 | fixed |
| firefox-esr (PTS) | bookworm | 140.12.0esr-1~deb12u1 | vulnerable |
| bookworm (security) | 140.14.0esr-1~deb12u1 | vulnerable | |
| trixie | 140.12.0esr-1~deb13u1 | vulnerable | |
| trixie (security) | 140.14.0esr-1~deb13u1 | vulnerable | |
| forky | 140.14.0esr-2 | vulnerable | |
| sid | 140.15.0esr-1 | fixed | |
| thunderbird (PTS) | bookworm | 1:140.12.0esr-1~deb12u1 | vulnerable |
| bookworm (security) | 1:140.14.0esr-1~deb12u1 | vulnerable | |
| trixie | 1:140.12.0esr-1~deb13u1 | vulnerable | |
| trixie (security) | 1:140.14.0esr-1~deb13u1 | vulnerable | |
| forky | 1:140.14.0esr-1 | vulnerable | |
| sid | 1:153.2.0esr-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) | 154.0-1 | |||
| firefox-esr | source | trixie | 140.15.0esr-1~deb13u1 | DSA-6481-1 | ||
| firefox-esr | source | (unstable) | 140.15.0esr-1 | |||
| thunderbird | source | (unstable) | 1:153.2.0esr-1 |
https://www.mozilla.org/en-US/security/advisories/mfsa2026-74/#CVE-2026-75874
https://www.mozilla.org/en-US/security/advisories/mfsa2026-84/#CVE-2026-75874
https://www.mozilla.org/en-US/security/advisories/mfsa2026-87/#CVE-2026-75874