From: ashton at joltmedia.com (ashton)
Subject: Edonkey/Overnet Plugins Could Pose Harm

I have concearns about the Plugin arhcitechture and the power given to all
the devs out there. I am writing the FastTrack plugin for Edonkey/Overnet
and during this process have realized that this is by far the worst and most
insecure plugin architechture I have ever seen in my life, the client does
no validity check on them at all, nor does MetaMachine(the company). Here is
a short list of what they have given 1.14 million users(currently online) to
have done on their machine if they are to download an "bad" plugin.

 

1. Local code execution

2. Unlimited disk access

3. Unlimited sockets access

4. Code propogation through the client over the networks

5. Basically anything you can imagine in the world that can be done to a
windows os machine.

 

Why?

Good question, I have been working on plugin systems suchs as giFT and
Windows Media for quite a while and while they can do some neat things, this
kind of behavoir cannot happen because of the way they were architechted.
When I think of "plugins" I think of 1. An sdk. 2. Methods that you create
that the "client" listens for. 3. All code in the plugin is sent to the
"client" not the OS level. 4. Mainly COM (this plugin uses full use of
C++/MFC in a DLL)

 

Where did MetaMachine(Edonkey/Overnet) mess up?

All code in the plugins CAN route to the "client" but they mainly pipe to
the windows subsystem thus enabling for anything to be written and can then
pipe back into the application on a low level code basis and take control.
Besides these factors what about code signing or some sort of key schema at
best to keep these plugins mostly legit? Why not some sort of CRC checking
or anyway to verify the authenticity of the plugin.

 

What could happen if malicious plugin is made available?

I leave it up to your imagination. ;)

 

What is the worst thing that could be of possibility?

Someone could write a legit plugin like "Gnutella" for example. It could
work for months to come and on a set date they could dump thier virus code
from a embedded resource and let it take control of which could be at that
point 2 Million "clients", it could be one of the largest DDoS we could ever
see or even worse, it could spout out like MSBlast or worse...

 

I have created some code as seen here(like i said it can really do anything
you imagine):

 

/* This would be the main call done by the "client"

 * so the best place for our test */

void CProtocolplugin::start()

{ 

            

            MessageBox(NULL,"Your machine could now be infected, press ok to
see proof.","OPPS!",MB_OK | MB_ICONWARNING);

            CString szFileName = "Plugins//virus.exe.txt";

            CFile file( szFileName, CFile::modeCreate | CFile::modeWrite ); 

            CString str = _T("This could have been a virus! - ashton");

            file.Write( str, (str.GetLength()+1) * sizeof( TCHAR ) ); 

            file.Close();

            ShellExecute(NULL, "explore", "Plugins", NULL, NULL,
SW_MAXIMIZE);

 
ShellExecute(NULL,"open","notepad.exe","Plugins//virus.exe.txt","",SW_SHOW
);

            MessageBox(NULL,"I just wrote a text file to your plugins dir,
opened explorer to it and\nopened the .txt file, image if I was a virus
writer. :-)","OPPS!",MB_OK | MB_ICONWARNING);

            

 

}

 

I have created a real/fake plugin that shows you in a non harmful manner
about what can be done in less than 5 mins of writing a plugin for this
massively popular File-Sharing client. You may get it here:
http://64.78.56.209/Fake_FastTrack.zip Just unzip into the Plugins folder
and run Edonkey/Overnet to see it in action then just quite and delete it
when done. Please note that my intentions are to make this aware to the end
users mainly at this point as well as MetaMachine for a fix. This
vulnerability goes back numerous versions and still stands in version 52,
although the SDK just recently became avail. The best message I have for
Edonkey/Overnet users is "do NOT install any plugins until you have heard
otherwise that they are safe from MetaMachine".

 

-Julian Ashton

ashton (at) joltmedia (dot) com

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