Description
Sandbox escape due to incorrect boundary conditions in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 146, Firefox ESR 115.31, Firefox ESR 140.6, Thunderbird 146, and Thunderbird 140.6.
Affected products
mozilla: firefox; mozilla: thunderbird
References6
- www.mozilla.org/security/advisories/mfsa2025-92/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2025-93/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2025-94/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2025-95/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2025-96/ Vendor Advisory
- bugzilla.mozilla.org/show_bug.cgi?id=1996473 Issue TrackingPermissions Required
Metrics
- CVSS 3.1
-
8.0
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N - EPSS — exploit probability
- 0% percentile: 31 · as of 11 November 2026
- CWE
- CWE-754
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