CVE-2019-9818: Mozilla Firefox

High severity, CVSS 8.3. EPSS: 1% chance of exploitation in the next 30 days.

A race condition is present in the crash generation server used to generate data for the crash reporter. This issue can lead to a use-after-free in the main process, resulting in a potentially exploitable crash and a sandbox escape. *Note: this vulnerability only affects Windows. Other operating systems are unaffected.*. This vulnerability affects Thunderbird < 60.7, Firefox < 67, and Firefox ESR < 60.7.

Affected products

• Mozilla Firefox: before 67.0 (fixed in 67.0)
• Mozilla Firefox ESR: before 60.7 (fixed in 60.7)
• Mozilla Thunderbird: before 60.7 (fixed in 60.7)

Published 2019-07-23. Last modified 2026-06-17.