Document Title:
===============
Easy FTP Pro 4.2 iOS - Script Code Inject Vulnerabilities


References (Source):
====================
http://www.vulnerability-lab.com/get_content.php?id=1291


Release Date:
=============
2014-08-05


Vulnerability Laboratory ID (VL-ID):
====================================
1291


Common Vulnerability Scoring System:
====================================
4.4


Product & Service Introduction:
===============================
The Best FTP and SFTP client for iPhone and iPad! Easy FTP is an FTP (File Transfer Protocol) and SFTP client for 
iPhone/iPod Touch. Easy FTP offer all the features of a desktop client. Also includes a web browser that allow to 
download files, audio player, mp4, avi,... video player, Dropbox, also helps you to access files on your remote 
computer (Mac, Windows, Linux), NAS Servers, and more.

( Copy of the Homepage: https://itunes.apple.com/en/app/easy-ftp-pro/id429071149 )


Abstract Advisory Information:
==============================
The Vulnerability Laboratory Research Team discovered two script code injection web vulnerabilities in the official Easy FTP Pro v4.2 iOS mobile application.


Vulnerability Disclosure Timeline:
==================================
2014-08-06: Public Disclosure (Vulnerability Laboratory)


Discovery Status:
=================
Published


Affected Product(s):
====================
Juan Ramon Rivero
Product: Easy FTP Pro - iOS Mobile Web Application 4.2


Exploitation Technique:
=======================
Remote


Severity Level:
===============
Medium


Technical Details & Description:
================================
Two script code injection web vulnerabilities has been discovered in the official Easy FTP Pro v4.2 iOS mobile application.
The vulnerability allows remote attackers to inject own malicious script codes to the application-side of the vulnerable module.

The first vulnerability is located in the vulnerable `foldername` value of the `easy ftp wifi` module. Local attackers are 
able to inject own malicious script codes in the vulnerable `foldername` input value.  The execution of the command occurs 
in the `File Dir Index Listing` module of the easy ftp pro v4.2 mobile application. The attacker is able to manipulate the 
local device values with physical or restricted acccess to compromise the mobile application by preparing to change the foldername. 
The encoding of the vulnerable values in the `File Dir Index Listing` module is broken.

The second vulnerability is also located in the `èasy ftp wifi` module. The same attack like on changing a foldername can 
be exploited by attackers through the regular filename validation. The attacker is able to manipulate the local device values 
with physical or restricted acccess on the app to compromise the mobile application by preparing to change the filename.

The attack vector of both issues are located on the application-side and the injection requires physical device access or a 
local low privileged device user account.

The security risk of the script code injection web vulnerabilities are estimated as medium with a cvss (common vulnerability 
scoring system) count of 3.8. Exploitation of the application-side vulnerabilities requires a low privileged iOS device 
account with restricted access and only low user interaction. Successful exploitation of the vulnerability results compromise 
of the iOS web-application or connected device components.

Request Method(s):
				[+] [Sync]

Vulnerable Module(s):
				[+] Add File & Rename File + Import
				[+] Add Folder & Rename Folder + Import

Vulnerable Parameter(s):
				[+] foldername
				[+] filename

Affected Module(s):
				[+] File Dir Index Listing


Proof of Concept (PoC):
=======================
The script code injection web vulnerabilities can be exploited by local attackers with low privileged or restricted device user account 
with physical access and without user interaction. For security demonstration or to reproduce the vulnerability follow the provided 
information and steps below to continue.


PoC #1:
--- PoC Session Logs [GET] (Execution) ---
Status: pending[OK]
GET http://localhost:8080/../[PERSISTENT INJECTED SCRIPT CODE!] 
   Request Header:
      Host[localhost:8080]
      User-Agent[Mozilla/5.0 (Windows NT 6.3; WOW64; rv:31.0) Gecko/20100101 Firefox/31.0]
      Referer[http://localhost:8080/]
-
Status: 200[OK]
 GET http://localhost:8080/index
   Request Header:
      Host[localhost:8080]
      User-Agent[Mozilla/5.0 (Windows NT 6.3; WOW64; rv:31.0) Gecko/20100101 Firefox/31.0]
      Referer[http://localhost:8080/]
-
Status: 200[OK]
GET http://localhost:8080/# 
   Request Header:
      Host[localhost:8080]
      User-Agent[Mozilla/5.0 (Windows NT 6.3; WOW64; rv:31.0) Gecko/20100101 Firefox/31.0]
  


PoC: Source Foldername - File Dir Index Listing
            <script type="text/javascript" charset="utf-8">
                function eliminaArchivo(archNombre){
                    $.post("/delete/"+archNombre,   
                           function(data) {    
                                cargaLista(rutaActual);
                           });
                }
                function comprueba(){
                    var fullPath = document.getElementById('uploadFile').value;
                    if (fullPath) {
                        var startIndex = (fullPath.indexOf('') >= 0 ? fullPath.lastIndexOf('') : fullPath.lastIndexOf('/'));
                        var filename = fullPath.substring(startIndex);
                        if (filename.indexOf('') === 0 || filename.indexOf('/') === 0) {
                            filename = filename.substring(1);
                        }
                        filenombre = filename;
                    }
                    
                    return true;
                }
                
                var rutaActual = '';
                function confirma(nombre){
                    var borrar = confirm("Do you really want to delete: "+unescape(nombre)+"?");
                    if (borrar == true){
                        //return true;
                        eliminaArchivo(nombre);
                    }
                    return false;
                }
				function cargaLista(ruta){
                    $("#filelist").empty();	
                    $("#folder").empty();	
                    var send = ruta;
                    if(ruta == '..'){
                        if(rutaActual.lastIndexOf('/')>=0)
                        send = rutaActual.substr(0,rutaActual.lastIndexOf('/'));
                        else
                        send = '';  
                    }
					$.ajaxSetup({cache: false});
                    $.getJSON('/files/'+send/*'/files/'+ruta*/,
                              function(data){
                              var shadow = false;
                              //console.log(data);
                              rutaActual = data.currentDir;
                              $('#folder').append('Current path: Documents/' +data.currentDir);
                              $.each(data.files, function(i,item){
                                     var trclass='';
                                     if (shadow)
                                     trclass= " class='shadow'";
                                     encodeName = (encodeURI(rutaActual)+'/'+item.name).replace("'", "'");
                                     var html = '';
                                     if(item.type == 'FILE')
html += "<tr" + trclass + "><td class='icon'> </td><td class='filename'><a href='/files/" + encodeName + "' class='file'>" + 
decodeURI(item.name) + "</a></td>" + "<td class='size'>" + item.tam + "</td>";else
html += "<tr" + trclass + "><td class='icon'><img src="folder.png" alt="folder" height=20 width=20  /></td><td class='filename'>
<a href='javascript:cargaLista("" + encodeURI(item.path).replace("'", "'") + "")' class='file'>" + decodeURI(item.name) + "</a></td>"+"<td class='size'> </td>";
html += "<td class='date'>" + item.date + "</td>" + 
"<td class='del'><a href='#' onclick='confirma(""+escape(decodeURI(encodeURI(rutaActual)+'/'+item.name)).replace("'", "'")+"")'><img src="delete.gif" 
alt="folder" height=20 width=20 style="border:0;" /></a></td></tr>";
                                     $(html).appendTo("#filelist");
                                     shadow = !shadow;
                                     });
                              })
                    .error(function(){
                            alert('Connection error. Check if the web sharing is on and the iphone/ipod still connected to the network.');
                           });
                    
                }
				$.ajaxSetup({cache: true});
                $(document).ready(function(){
                                  cargaLista('');
                                  });
                </script>


PoC #2:
--- PoC Session Logs [GET] (Execution) ---
Status: 200[OK]
GET http://localhost:8080/files/%3E[PERSISTENT INJECTED SCRIPT CODE!] 
   Request Header:
      Host[localhost:8080]
      User-Agent[Mozilla/5.0 (Windows NT 6.3; WOW64; rv:31.0) Gecko/20100101 Firefox/31.0]
      Accept[application/json, text/javascript, */*; q=0.01]
      Accept-Language[de,en-US;q=0.7,en;q=0.3]
      Accept-Encoding[gzip, deflate]
      X-Requested-With[XMLHttpRequest]
      Referer[http://localhost:8080/]
      Connection[keep-alive]
   Response Header:
      Accept-Ranges[bytes]
      Content-Length[42]
      Date[Wed, 06 Aug 2014 10:37:15 GMT]
-
Status: pending[]
GET http://localhost:8080/..%3C/[PERSISTENT INJECTED SCRIPT CODE EXECUTION	!]  
   Request Header:
      Host[localhost:8080]
      User-Agent[Mozilla/5.0 (Windows NT 6.3; WOW64; rv:31.0) Gecko/20100101 Firefox/31.0]
      Accept[text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8]
      Accept-Language[de,en-US;q=0.7,en;q=0.3]
      Accept-Encoding[gzip, deflate]
      Referer[http://localhost:8080/]




PoC: Source Filename - File Dir Index Listing

<div id="tlista">
<table border="0" cellpadding="0" cellspacing="0">
<thead>
<tr>
<th class="icon"><a href="javascript:cargaLista('..')" class="file"> <img src="back.png" alt="back" border="0/" height="20" width="20"></a>
</th>
<th class="filename">
Name
</th>
<th class="size">
Size
</th>
<th class="date">
Modified
</th>
<th class="del">
<a href="javascript:cargaLista(rutaActual)" class="file"> <img src="refresh.png" alt="back" border="0/" height="16" width="16"></a>
</th>
</tr>
</thead>
</table>
<table border="0" cellpadding="0" cellspacing="0">
<tbody id="filelist"><tr><td class="icon"><img src="folder.png" alt="folder" height="20" width="20"></td><td class="filename">
<a href="javascript:cargaLista("[PERSISTENT INJECTED SCRIPT CODE!]  )" class="file">[PERSISTENT INJECTED SCRIPT CODE!] "></a></td>
<td class='size'> </td><td class='date'>06.08.14 12:27</td><td class='del'><a href='#' onclick='confirma("[PERSISTENT INJECTED SCRIPT CODE!]  ")'>
<img src="delete.gif" alt="folder" height=20 width=20 style="border:0;" /></a></td></tr></tbody></table></iframe></a></td></tr></tbody>


Solution - Fix & Patch:
=======================
The vulnerabilities can be patched by a secure parse and encode of the vulnerable file- and foldername values.
Restrict the local app user input on both values to prevent further command injection attacks. Do not forget to parse the affected output listing in the file dir listing.


Security Risk:
==============
The security risk of both script code injection web vulnerabilities in the file- and foldername values are estimated as medium. (CVSS 4.4)


Credits & Authors:
==================
Vulnerability Laboratory [Research Team] - Benjamin Kunz Mejri (bkm@evolution-sec.com) [www.vulnerability-lab.com]


Disclaimer & Information:
=========================
The information provided in this advisory is provided as it is without any warranty. Vulnerability Lab disclaims all warranties, either 
expressed or implied, including the warranties of merchantability and capability for a particular purpose. Vulnerability-Lab or its suppliers 
are not liable in any case of damage, including direct, indirect, incidental, consequential loss of business profits or special damages, even 
if Vulnerability-Lab or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation 
of liability for consequential or incidental damages so the foregoing limitation may not apply. We do not approve or encourage anybody to break 
any vendor licenses, policies, deface websites, hack into databases or trade with fraud/stolen material.

Domains:    www.vulnerability-lab.com   	- www.vuln-lab.com			       		- www.evolution-sec.com
Contact:    admin@vulnerability-lab.com 	- research@vulnerability-lab.com 	       		- admin@evolution-sec.com
Section:    dev.vulnerability-db.com	 	- forum.vulnerability-db.com 		       		- magazine.vulnerability-db.com
Social:	    twitter.com/#!/vuln_lab 		- facebook.com/VulnerabilityLab 	       		- youtube.com/user/vulnerability0lab
Feeds:	    vulnerability-lab.com/rss/rss.php	- vulnerability-lab.com/rss/rss_upcoming.php   		- vulnerability-lab.com/rss/rss_news.php
Programs:   vulnerability-lab.com/submit.php  	- vulnerability-lab.com/list-of-bug-bounty-programs.php	- vulnerability-lab.com/register/

Any modified copy or reproduction, including partially usages, of this file requires authorization from Vulnerability Laboratory. Permission to 
electronically redistribute this alert in its unmodified form is granted. All other rights, including the use of other media, are reserved by 
Vulnerability-Lab Research Team or its suppliers. All pictures, texts, advisories, source code, videos and other information on this website 
is trademark of vulnerability-lab team & the specific authors or managers. To record, list (feed), modify, use or edit our material contact 
(admin@vulnerability-lab.com or research@vulnerability-lab.com) to get a permission.

				Copyright © 2014 | Vulnerability Laboratory [Evolution Security]