CVE-2026-8390highCWE-416 CWE-825

CVE-2026-8390: high-severity vulnerability in Mozilla Firefox

Use-after-free in the JavaScript: WebAssembly component

Published 12 May 2026 · Updated 15 Jul 2026

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21Vexday Risk Score

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

ssvc Trackcvss 7.3epss 0.5%

Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 150.0.3.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

Affected products

Mozilla · Firefox

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References

https://access.redhat.com/security/cve/CVE-2026-8390 https://bugzilla.mozilla.org/show_bug.cgi?id=2038081 https://bugzilla.redhat.com/show_bug.cgi?id=2476474 https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-8390.json https://www.mozilla.org/security/advisories/mfsa2026-45/