Information disclosure due to incorrect boundary conditions in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 154, Firefox ESR 115.39, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.
Fix
Patch, vendor advisory and mitigation references on NVD 7
- https://www.mozilla.org/security/advisories/mfsa2026-74/ Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-75/ Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-76/ Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-77/ Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-78/ Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-79/ Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-80/ Vendor Advisory
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 5
- CwesCWE-119NVD modified 2026-10-28 17:18
- Cpes+2 CPE criteria (now 2)NVD modified 2026-10-28 17:18
- StatusPublished → ModifiedNVD modified 2026-10-28 17:18
- CVSS8.8 (v3.1, CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H)NVD modified 2026-10-28 17:18
- First seenunscored · mozillaNVD modified 2026-10-28 16:35
Affected (CPE criteria) 2
cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*
References 8
- https://bugzilla.mozilla.org/show_bug.cgi?id=2059997 Permissions Required
- https://www.mozilla.org/security/advisories/mfsa2026-74/ Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-75/ Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-76/ Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-77/ Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-78/ Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-79/ Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-80/ Vendor Advisory