CVE-2025-14330: Mozilla Firefox

Critical severity, CVSS 9.8. EPSS: 0.5% chance of exploitation in the next 30 days.

JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 146, Firefox ESR 140.6, Thunderbird 146, and Thunderbird 140.6.

Affected products

• Mozilla Firefox: before 140.6.0 (fixed in 140.6.0); before 146.0 (fixed in 146.0)
• Mozilla Thunderbird: before 140.6.0 (fixed in 140.6.0); before 146.0 (fixed in 146.0)

Published 2025-12-09. Last modified 2026-10-07.