Files or Directories Accessible to External Parties

// A forward target chosen by the caller names a file on the server, so the response can be
// made to contain a page that was never meant to be served directly.
class NavigationServlet extends HttpServlet {
  @throws[IOException]
  override def doGet(request: HttpServletRequest, response: HttpServletResponse): Unit = {
    try {
      val target = request.getParameter("target")

      // VULNERABLE: Files or Directories Accessible to External Parties
      val byPath = new ActionForward(target)
      // VULNERABLE: Files or Directories Accessible to External Parties
      val byPathRedirecting = new ActionForward(target, true)
      // VULNERABLE: Files or Directories Accessible to External Parties
      val namedByPath = new ActionForward("next", target, true)
      // VULNERABLE: Files or Directories Accessible to External Parties
      val namedByPathAgain = new ActionForward("next", target, true)
      val assignedLater = new ActionForward
      // VULNERABLE: Files or Directories Accessible to External Parties
      assignedLater.setPath(target)

      // In this overload the value lands in the NAME, not the path, so it is not reported.
      val byName = new ActionForward(target, "/next.jsp", true)

      // VULNERABLE: Files or Directories Accessible to External Parties
      val view = new ModelAndView(target)
      val emptyView = new ModelAndView
      // VULNERABLE: Files or Directories Accessible to External Parties
      emptyView.setViewName(target)
    } catch {
      case e: Exception =>
        System.out.println(e)
    }
  }

  @throws[IOException]
}