CVE-2023-25734: Mozilla Firefox

High severity, CVSS 8.1. EPSS: 0.8% chance of exploitation in the next 30 days.

After downloading a Windows <code>.url</code> shortcut from the local filesystem, an attacker could supply a remote path that would lead to unexpected network requests from the operating system. This also had the potential to leak NTLM credentials to the resource.<br>*This bug only affects Firefox on Windows. Other operating systems are unaffected.*. This vulnerability affects Firefox < 110, Thunderbird < 102.8, and Firefox ESR < 102.8.

Affected products

• Mozilla Firefox: before 110.0 (fixed in 110.0)
• Mozilla Firefox ESR: before 102.8 (fixed in 102.8)
• Mozilla Thunderbird: before 102.8 (fixed in 102.8)

Published 2023-06-02. Last modified 2026-06-17.