Description
Thunderbird ignored paths when checking the validity of navigations in a frame. This vulnerability was fixed in Firefox 141, Firefox ESR 140.1, Thunderbird 141, and Thunderbird 140.1.
Affected products
mozilla: firefox; mozilla: thunderbird
References5
- www.mozilla.org/security/advisories/mfsa2025-56/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2025-59/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2025-61/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2025-63/ Vendor Advisory
- bugzilla.mozilla.org/show_bug.cgi?id=1808979 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: 19 · as of 8 November 2026
- CWE
- CWE-345
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