Incorrect boundary conditions in the SVG component. This vulnerability was fixed in Firefox 158.0.1 and Thunderbird 158.0.1.
https://www.mozilla.org/security/advisories/mfsa2026-114/
https://www.mozilla.org/security/advisories/mfsa2026-111/
https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-104980
https://bugzilla.mozilla.org/show_bug.cgi?id=2079938
Source: Mitre, NVD
Published: 2026-10-20
Updated: 2026-10-29
Base Score: 10
Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C
Severity: Critical
Base Score: 9.8
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS: 0.00489