CVE-2026-2634: Mozilla Firefox

Critical severity, CVSS 9.8. EPSS: 0.5% chance of exploitation in the next 30 days.

Malicious scripts could cause desynchronization between the address bar and web content before a response is received in Firefox iOS, allowing attacker-controlled pages to be presented under spoofed domains. This vulnerability was fixed in Firefox for iOS 147.4.

Affected products

• Mozilla Firefox: before 147.4 (fixed in 147.4)

Published 2026-02-24. Last modified 2026-06-17.