WordPress and WordPress plugin are both products of the WordPress Foundation. WordPress is a blogging platform developed using the PHP language. WordPress plugin is an application plugin. WordPress Showing URL in QR Code plugin 0.0.1 and earlier versions have a cross-site scripting vulnerability, which stems from the lack of cross-site request forgery checks and the lack of cleanup and escaping of user input when updating settings, which can be exploited to inject cross-site code to launch an XSS attack.