CVE-2022-22743: Mozilla Firefox

Medium severity, CVSS 4.3. EPSS: 0.7% chance of exploitation in the next 30 days.

When navigating from inside an iframe while requesting fullscreen access, an attacker-controlled tab could have made the browser unable to leave fullscreen mode. This vulnerability affects Firefox ESR < 91.5, Firefox < 96, and Thunderbird < 91.5.

Affected products

• Mozilla Firefox: before 96.0 (fixed in 96.0)
• Mozilla Firefox ESR: before 91.5 (fixed in 91.5)
• Mozilla Thunderbird: before 91.5 (fixed in 91.5)

Published 2022-12-22. Last modified 2026-06-17.