Description
Site isolation issue in the DOM: Navigation 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=2055028 Permissions Required
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 8 · as of 8 November 2026
- CWE
- CWE-346
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