Input validation vulnerability in Featured Image from URL (FIFU) 4.5.3

The Featured Image from URL plugin for WordPress is vulnerable to a type of security issue called Stored Cross-Site Scripting. This type of vulnerability can allow attackers, who have a certain level of access to the website, to place malicious code on pages of the website. This code will be executed every time someone visits the page, potentially allowing them to access sensitive information or gain control of the website. All versions of the plugin, up to and including 4.5.3, are affected by this vulnerability due to a lack of security measures that prevent malicious code from being added.