CVE-2024-3854: Mozilla Firefox

High severity, CVSS 8.8. EPSS: 0.7% chance of exploitation in the next 30 days.

In some code patterns the JIT incorrectly optimized switch statements and generated code with out-of-bounds-reads. This vulnerability affects Firefox < 125, Firefox ESR < 115.10, and Thunderbird < 115.10.

Affected products

• Mozilla Firefox: before 115.10 (fixed in 115.10); before 125.0 (fixed in 125.0)
• Mozilla Thunderbird: before 115.10 (fixed in 115.10)

Published 2024-04-16. Last modified 2026-06-17.