  public ModalDialog wantsNotificationOnClose()
  {
    mainContainer.add(new AjaxEventBehavior("hidden") {
      @Override
      protected void onEvent(final AjaxRequestTarget target)
      {
        csrfTokenHandler.onSubmit();
        handleCloseEvent(target);
      }
    });
    return this;
  }
The web application does not, or can not, sufficiently verify whether a well-formed, valid, consistent request was intentionally provided by the user who submitted the request.