Input validation vulnerability in WebLibrarian 3.5.8.1

The WebLibrarian plugin for WordPress is not safe to use in versions up to, and including, 3.5.8.1. It is vulnerable to a type of attack called Reflected Cross-Site Scripting, which could allow someone to inject malicious code into a page if a user clicks on something they shouldn’t, such as a link. This is because the plugin does not properly check and prevent the input of dangerous code, or escape the code it does receive.