CVE-2026-4687criticalCWE-120CWE-501

CVE-2026-4687: critical vulnerability in Mozilla Firefox

Sandbox escape due to incorrect boundary conditions in the Telemetry component

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28Vexday Risk Score

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

ssvc Trackcvss 9.6epss 0.6%
Sandbox escape due to incorrect boundary conditions in the Telemetry 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:R/S:C/C:H/I:H/A:H
Affected products
Mozilla · FirefoxMozilla · Thunderbird
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