CVE-2026-0878

high

Description

Sandbox escape due to incorrect boundary conditions in the Graphics: CanvasWebGL component. This vulnerability affects Firefox < 147, Firefox ESR < 140.7, Thunderbird < 147, and Thunderbird < 140.7.

References

https://www.mozilla.org/security/advisories/mfsa2026-05/

https://www.mozilla.org/security/advisories/mfsa2026-04/

https://www.mozilla.org/security/advisories/mfsa2026-03/

https://www.mozilla.org/security/advisories/mfsa2026-01/

https://bugzilla.mozilla.org/show_bug.cgi?id=2003989

Details

Source: Mitre, NVD

Published: 2026-01-13

Updated: 2026-01-15

Risk Information

CVSS v2

Base Score: 7.6

Vector: CVSS2#AV:N/AC:H/Au:N/C:C/I:C/A:C

Severity: High

CVSS v3

Base Score: 8

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N