CVE-2024-11704: Mozilla Firefox

Critical severity, CVSS 9.8. EPSS: 0.9% chance of exploitation in the next 30 days.

A double-free issue could have occurred in `sec_pkcs7_decoder_start_decrypt()` when handling an error path. Under specific conditions, the same symmetric key could have been freed twice, potentially leading to memory corruption. This vulnerability affects Firefox < 133, Thunderbird < 133, Firefox ESR < 128.7, and Thunderbird < 128.7.

Affected products

• Mozilla Firefox: before 128.7.0 (fixed in 128.7.0); before 133.0 (fixed in 133.0)
• Mozilla Thunderbird: before 128.7.0 (fixed in 128.7.0); from 129.0, before 133.0 (fixed in 133.0)

Published 2024-11-26. Last modified 2026-06-17.