CVE-2026-2776criticalCWE-119

CVE-2026-2776: critical vulnerability in Mozilla Firefox

Sandbox escape due to incorrect boundary conditions in the Telemetry component in External Software

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28Vexday Risk Score

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

ssvc Trackcvss 10epss 0.6%
Sandbox escape due to incorrect boundary conditions in the Telemetry component in External Software. This vulnerability was fixed in Firefox 148, Firefox ESR 115.33, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.
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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