Description
Starting in Thunderbird 143, the use of the native messaging API by web extensions on Windows could lead to crashes caused by use-after-free memory corruption. This vulnerability was fixed in Firefox 144 and Thunderbird 144.
Affected products
mozilla: firefox; mozilla: thunderbird; microsoft: windows
References3
- www.mozilla.org/security/advisories/mfsa2025-81/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2025-84/ Vendor Advisory
- bugzilla.mozilla.org/show_bug.cgi?id=1991950 Issue TrackingPermissions Required
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 29 · as of 9 November 2026
- CWE
- CWE-416
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