Secure JSF Application – why you should always define a servlet mapping

If you deploy a JSF application in WildFly 8, you can omit to define the JSF serlvet mapping. In this case three default mappings will be active out of the box.

  • <context-root>/faces/*
  • <context-root>/*.jsf
  • <context-root>/*.faces

Tested on WildFly 8.0.0.CR1 and JBoss EAP 6.2.0.GA

This behavior is not mentioned in the JSF 2.1 spec. But it explicitly allows implementations to use proprietary means to invoke the JSF lifecycle.

In addition to FacesServlet, JSF implementations may support other ways to invoke the JavaServer Faces request processing lifecycle, but applications that rely on these mechanisms will not be portable.

This default mapping can be problematic as it provides several path to access resources within your web application. Especially if you use security constraints to protect parts of your application. For instance if you restrict access to <context-root>/secure/* using a security constraint in your web.xml, web resources can still be accessed via <context-root>/faces/.
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