CVE-2026-8391mediumCWE-119CWE-20CWE-475CWE-79

CVE-2026-8391: medium-severity vulnerability in Mozilla Firefox

Other issue in the JavaScript Engine component

Published · Updated

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13Vexday Risk Score

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

ssvc Trackcvss 5.3epss 0.3%
Other issue in the JavaScript Engine component. This vulnerability was fixed in Firefox 150.0.3, Firefox ESR 115.36, Firefox ESR 140.11, and Thunderbird 140.11.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Affected products
Mozilla · FirefoxMozilla · Thunderbird
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