Cross-site Scripting in Apache Struts

Multiple Cross-Site Scripting (XSS) in XWork generated error pages in Apache Struts. By default, XWork doesn't escape action's names in automatically generated error page, allowing for a successful XSS attack. When Dynamic Method Invocation (DMI) is enabled, the action name is generated dynamically base on request parameters. This allows to call non-existing page and method to produce error page with injected code as below. As of Struts 2.2.3 the action names are escaped when automatically generated error pages are rendered.