CVE-2026-8390: Mozilla Firefox

High severity, CVSS 7.3. EPSS: 0.3% chance of exploitation in the next 30 days.

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

Affected products

• Mozilla Firefox: before 150.0.3 (fixed in 150.0.3)

Published 2026-05-12. Last modified 2026-07-15.