1. OVERVIEW

The gDoc Fusion application is vulnerable to Insecure DLL Hijacking
Vulnerability. Similar terms that describe this vulnerability have
been come up with Remote Binary Planting, and Insecure DLL
Loading/Injection/Hijacking/Preloading.


2. PRODUCT DESCRIPTION

gDoc Fusion makes it simple and quick to compile a single document
from multiple different PC files. Just drag the
documents--presentations, spreadsheets, written documents, images,
PDF, and more than 200 other file types--into Fusion; flip through
them quickly with FlickView browser; pick the pages you want and
arrange them in any order you like; if you wish, add comments, make
small text edits, or redact information; and Save the finished
documents in either Word or PDF format. You don't have to do any
formatting or conversion--gDoc Fusion handles it all for you. Also
includes free ultilty for multi-format document viewing and PDF
creation.


3. VULNERABILITY DESCRIPTION

The gDoc Fusion application passes an insufficiently qualified path in
loading its external libraries -
"wintab32.dll, ssleay32.dll" when a user opens its associated file
with extensions - dwfx, jtx, pdf, xps .


4. VERSIONS AFFECTED

2.5.1 and probably lower versions


5. PROOF-OF-CONCEPT/EXPLOIT

http://core.yehg.net/lab/pr0js/advisories/dll_hijacking/gdocfusion/poc/movie/gdocfusion_2.5.1-dll-hijacking.mp4
http://core.yehg.net/lab/pr0js/advisories/dll_hijacking/gdocfusion/poc/gdocfusion_2.5.1-dll-hijacking-poc.zip

Tested Platform: Windows XP Service Pack 3 (Fresh Windows)


6. IMPACT

Attackers can trigger a successful exploit against a victim user in a
number of ways such as placing a malicious external
library file made as hidden attribute and a seemingly interesting file
in network shares, usb drives, file sharing networks,
social networks, ..etc	


7. SOLUTION

Fixed version from the vendor has not been released yet.
However, it is suggested that the following workarounds be deployed by
users to protect increasing mass exploitation of this
vulnerability class:
- Disable loading of libraries from WebDAV and remote network shares
- Disable the WebClient service
Please see workaround solution links in References section.


8. VENDOR

Global Graphics Software Ltd.
http://www.globalgraphics.com/en/gdoc/gdoc-fusion


9. CREDIT

This vulnerability was discovered by Aung Khant, http://yehg.net, YGN
Ethical Hacker Group, Myanmar.


10. DISCLOSURE TIME-LINE

09-13-2010: notified vendor
09-13-2010: vulnerability disclosed


11. REFERENCES

Original Advisory URL:
http://core.yehg.net/lab/pr0js/advisories/dll_hijacking/[gdocfusion]_2.5.1_insecure_dll_hijacking
Workaround Solution: http://support.microsoft.com/kb/2264107
Workaround Solution:
https://www.microsoft.com/technet/security/advisory/2269637.mspx#EGF
Developer Solution:
http://msdn.microsoft.com/en-us/library/ff919712%28v=VS.85%29.aspx
Unofficial DLL Hijacking List:
http://www.corelan.be:8800/index.php/2010/08/25/dll-hijacking-kb-2269637-the-unofficial-list/
Testing for DLL Hijacking:
http://core.yehg.net/lab/pr0js/view.php/when_testing_for_dll_hijacking.txt

#yehg [09-13-2010]

_______________________________________________
Full-Disclosure - We believe in it.
Charter: http://lists.grok.org.uk/full-disclosure-charter.html
Hosted and sponsored by Secunia - http://secunia.com/