CVE-2025-6428: Mozilla Firefox

Medium severity, CVSS 4.3. EPSS: 0.2% chance of exploitation in the next 30 days.

When a URL was provided in a link querystring parameter, Firefox for Android would follow that URL instead of the correct URL, potentially leading to phishing attacks. *This bug only affects Firefox for Android. Other versions of Firefox are unaffected.*. This vulnerability was fixed in Firefox 140.

Affected products

• Mozilla Firefox: before 140.0 (fixed in 140.0)

Published 2025-06-24. Last modified 2026-09-30.