Description
Sandbox escape due to use-after-free in the Graphics component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.
Affected products
mozilla: firefox; mozilla: thunderbird
References8
- www.mozilla.org/security/advisories/mfsa2026-100/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-101/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-102/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-103/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-97/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-98/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-99/ Vendor Advisory
- bugzilla.mozilla.org/show_bug.cgi?id=2071067 Permissions Required
Metrics
- CVSS 3.1
-
9.6
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 25 · as of 10 November 2026
- CWE
- CWE-416
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