CVE-2026-4700criticalCWE-288CWE-444

CVE-2026-4700: critical vulnerability in Mozilla Firefox

Mitigation bypass in the Networking: HTTP component

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28Vexday Risk Score

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

ssvc Trackcvss 9.8epss 0.9%
Mitigation bypass in the Networking: HTTP component. This vulnerability was fixed in Firefox 149, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected products
Mozilla · FirefoxMozilla · Thunderbird
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