Description
Use-after-free in the Widget 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=2049352 Permissions Required
Metrics
- CVSS 3.1
-
8.8
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 25 · as of 10 November 2026
- CWE
- CWE-416
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