CVE-2025-5265: Mozilla Firefox

Medium severity, CVSS 4.8. EPSS: 0.2% chance of exploitation in the next 30 days.

Due to insufficient escaping of the ampersand character in the “Copy as cURL” feature, an attacker could trick a user into using this command, potentially leading to local code execution on the user's system. *This bug only affects Firefox for Windows. Other versions of Firefox are unaffected.*. This vulnerability was fixed in Firefox 139, Firefox ESR 115.24, Firefox ESR 128.11, Thunderbird 139, and Thunderbird 128.11.

Affected products

• Mozilla Firefox: before 115.24.0 (fixed in 115.24.0); before 139.0 (fixed in 139.0); from 116.0, before 128.11.0 (fixed in 128.11.0)

Published 2025-05-27. Last modified 2026-10-05.