Description
Thunderbird cached CORS preflight responses across IP address changes. This allowed circumventing CORS with DNS rebinding. This vulnerability was fixed in Firefox 141, Firefox ESR 140.1, Thunderbird 141, and Thunderbird 140.1.
Affected products
mozilla: firefox; mozilla: thunderbird
References6
- 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=1960834 Permissions Required
- www.kb.cert.org/vuls/id/652514
Metrics
- CVSS 3.1
-
8.1
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N - EPSS — exploit probability
- 0% percentile: 39 · as of 8 November 2026
- CWE
- CWE-350
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