by Kastro
Paper/Archive/CVE-2026-75874

CVE-2026-75874

Mozilla Firefox — Sandbox escape in the Remote Settings Client component

EPSS 0.5%CVSS 10.0
critical.is priorityof 100
38
CVSS 10.0 (ADP)10.0 / 10 × 3030.0Not in CISA KEV+300.0EPSS percentile 39.5.395 × 207.9No public exploit+100.0SSVC exploitation: none+100.0
Description · from the CVE record

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.

Affected

ProductAffectedFixed inSource
Firefoxsee advisory115.40CNA
Thunderbirdsee advisory140.15CNA

Scores by source

CISA ADP10.0CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
CISA ADPSSVCExploitation: none · Automatable: yes · Technical impact: total

References

refbugzilla.mozilla.org/show_bug.cgi?id=2039972refmozilla.org/security/advisories/mfsa2026-74refmozilla.org/security/advisories/mfsa2026-78refmozilla.org/security/advisories/mfsa2026-83refmozilla.org/security/advisories/mfsa2026-84refmozilla.org/security/advisories/mfsa2026-85refmozilla.org/security/advisories/mfsa2026-87refmozilla.org/security/advisories/mfsa2026-88