CVE-2024-7521: Mozilla Firefox

High severity, CVSS 8.8. EPSS: 0.6% chance of exploitation in the next 30 days.

Incomplete WebAssembly exception handing could have led to a use-after-free. This vulnerability affects Firefox < 129, Firefox ESR < 115.14, Firefox ESR < 128.1, Thunderbird < 128.1, and Thunderbird < 115.14.

Affected products

• Mozilla Firefox: before 129.0 (fixed in 129.0)
• Mozilla Firefox ESR: before 115.14.0 (fixed in 115.14.0); version 128.0 only
• Mozilla Thunderbird: before 115.14.0 (fixed in 115.14.0); version 128.0.1 only

Published 2024-08-06. Last modified 2026-06-17.