CVE-2026-124900

EUVD-2026-120927
Sandbox escape due to use-after-free in the DOM: Service Workers component. This vulnerability was fixed in Firefox 160 and Thunderbird 160.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
mozillaCNA
9.6 CRITICAL
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Early Detection
Affected products identified ahead of NVD analysis through intelligence sources (CNA/ADP records, vendor advisories, Enginsight analysis).
VendorProductVersionSource
mozillafirefox
𝑥
< 160
CNA
mozillathunderbird
𝑥
< 160
CNA
Debian logo
Debian Releases
Debian Product
Codename
firefox
sid
vulnerable
Common Weakness Enumeration
References
https://bugzilla.mozilla.org/show_bug.cgi?id=2083116
https://www.mozilla.org/security/advisories/mfsa2026-125/
https://www.mozilla.org/security/advisories/mfsa2026-128/