CVE-2026-12291highCWE-416CWE-825

CVE-2026-12291: high-severity vulnerability in Mozilla Firefox

Use-after-free in the Networking: HTTP component

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21Vexday Risk Score

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

ssvc Trackcvss 8.8epss 0.4%
Use-after-free in the Networking: HTTP component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Firefox ESR 115.37, Thunderbird 152, and Thunderbird 140.12.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Affected products
Mozilla · FirefoxMozilla · Thunderbird
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