Input validation vulnerability in Add Link to Facebook 1.216

The Add Link to Facebook plugin, which is used to link WordPress websites to Facebook, is vulnerable to a type of attack called Stored Cross-Site Scripting. This type of attack allows an administrator-level attacker to inject malicious code (such as web scripts) into the website, which will then be executed whenever a user visits the page. Versions of the plugin up to and including 1.215 are vulnerable due to inadequate input checking and output escaping.