CVE-2026-4689criticalCWE-120CWE-190

CVE-2026-4689: critical vulnerability in Mozilla Firefox

Sandbox escape due to incorrect boundary conditions, integer overflow in the XPCOM component

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28Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 10epss 0.7%
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:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
Affected products
Mozilla · FirefoxMozilla · Thunderbird
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