CVE-2020-12407: Mozilla Firefox

Medium severity, CVSS 6.5. EPSS: 1% chance of exploitation in the next 30 days.

Mozilla Developer Nicolas Silva found that when using WebRender, Firefox would under certain conditions leak arbitrary GPU memory to the visible screen. The leaked memory content was visible to the user, but not observable from web content. This vulnerability affects Firefox < 77.

Affected products

• Mozilla Firefox: before 77.0 (fixed in 77.0)

Published 2020-07-09. Last modified 2026-06-17.