apache struts2 remote code execute

this method was published at xcon2012 xcon.xfocus.net. kxlzx http://www.inbreak.net flow this and step by step: 1, down load struts2-showcase from struts.apache.org 2, run struts2-showcase. 3, open url: http://localhost:8080/struts2-showcase/skill/edit.action?skillName=SPRING-DEV 4, write skill...