Description
Same-origin policy bypass in the Request Handling component. This vulnerability was fixed in Firefox 146, Firefox ESR 115.31, Firefox ESR 140.6, Thunderbird 146, and Thunderbird 140.6.
Affected products
mozilla: firefox; mozilla: thunderbird
References6
- www.mozilla.org/security/advisories/mfsa2025-92/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2025-93/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2025-94/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2025-95/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2025-96/ Vendor Advisory
- bugzilla.mozilla.org/show_bug.cgi?id=2000218 Issue TrackingPermissions Required
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N - EPSS — exploit probability
- 0% percentile: 10 · as of 11 November 2026
- CWE
- CWE-346
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