CRITICAL 10.0
CVE-2026-4689
Sandbox escape due to incorrect boundary conditions, integer overflow in the XPCOM component. This vulnerability was fixed in Firefox 149, Firefox ESR 115.34, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.
CVSS v3
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
EPSS
0.0%
percentile 8.6%
Affected tracked apps
Vulnerable CPE configurations
| Vendor | Product | Platform | Versions | CPE 2.3 URI |
|---|---|---|---|---|
| mozilla | thunderbird | Windows | <140.9.0 | cpe:2.3:a:mozilla:thunderbird:*:*:*:*:esr:*:*:* |
| mozilla | thunderbird | Windows | <149.0 | cpe:2.3:a:mozilla:thunderbird:*:*:*:*:-:*:*:* |