Description
Spoofing issue in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 155, Firefox ESR 153.2, Thunderbird 155, and Thunderbird 153.2.
Affected products
mozilla: firefox; mozilla: thunderbird
References5
- www.mozilla.org/security/advisories/mfsa2026-82/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-85/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-86/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-88/ Vendor Advisory
- bugzilla.mozilla.org/show_bug.cgi?id=2051146 Issue TrackingPermissions Required
Metrics
- CVSS 3.1
-
4.3
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N - EPSS — exploit probability
- 0% percentile: 3 · as of 8 November 2026
- CWE
- CWE-346CWE-451
Could this be exploited in your environment?
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