Description
Undefined behavior in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 148, Firefox ESR 115.33, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.
Affected products
mozilla: firefox; mozilla: thunderbird
References10
- www.mozilla.org/security/advisories/mfsa2026-13/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-14/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-15/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-16/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-17/ Vendor Advisory
- bugzilla.mozilla.org/show_bug.cgi?id=2014593 Issue TrackingPermissions Required
- access.redhat.com/errata/RHSA-2026:3338
- access.redhat.com/errata/RHSA-2026:3339
- access.redhat.com/errata/RHSA-2026:3361
- access.redhat.com/errata/RHSA-2026:3491
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 1% percentile: 56 · as of 12 November 2026
- CWE
- CWE-125
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