CVE-2026-8952: Mozilla Firefox

High severity, CVSS 8.8. EPSS: 0.4% chance of exploitation in the next 30 days.

Privilege escalation in the Application Update component. This vulnerability was fixed in Firefox 151 and Thunderbird 151.

Affected products

• Mozilla Firefox: before 151.0.0 (fixed in 151.0.0)
• Mozilla Thunderbird: before 151.0.0 (fixed in 151.0.0)

Published 2026-05-19. Last modified 2026-06-17.