Improper neutralization of input during web page generation in Apache Wicket. org.apache.wicket.ajax.AjaxNewWindowNotifyingBehavior notices that a page instance has been opened in a second browser window or tab. It asks the browser for the value of window.name, which reaches the server as the request parameter windowName, and remembers what the browser reported in a field of the behaviour. That field is part of the page's serialized state, so the remembered value stays in the page store for as long as the page instance does. On every later render of that page instance the behaviour builds the precondition of its Ajax call by substituting the remembered value into a single-quoted JavaScript s