The Writeprint Stylometry plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the 'p' GET parameter in all versions up to and including 0.1. This is due to insufficient input sanitization and output escaping in the bjl_wprintstylo_comments_nav() function. The function directly outputs the $_GET['p'] parameter into an HTML href attribute without any escaping. This makes it possible for authenticated attackers with Contributor-level permissions or higher to inject arbitrary web scripts in pages that execute if they can successfully trick another user into performing an action such as clicking on a link.