The Featured Image from URL (FIFU) plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the fifu_input_url parameter in all versions up to, and including, 4.6.2 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with contributor access or higher, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

The Featured Image from URL (FIFU) plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the featured image alt text in all versions up to, and including, 4.5.3 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

The Featured Image from URL (FIFU) WordPress plugin before 4.0.1 does not validate, sanitise and escape some of its settings, which could allow high privilege users such as admin to perform Stored Cross-Site Scripting attacks when the unfiltered_html capability is disallowed (for example in multisite setup)

The Featured Image from URL (FIFU) WordPress plugin before 4.0.1 does not have CSRF check in place when updating its settings, which could allow attackers to make a logged in admin change them via a CSRF attack. Furthermore, due to the lack of validation, sanitisation and escaping in some of them, it could also lead to Stored XSS issues