False uploads through NAPSTER

From: James Rowley (James.ROWLEYat_private)
Date: Mon Feb 21 2000 - 01:20:55 PST

  • Next message: Darren Reed: "Re: Recent Attacks"

    Hi folks,
    
    Something that always puzzles me is that there must be a way to upload other
    files than MP3's through Napster by changing the file extension to .mp3
    
    I tried this & it didn't work, however there simply must be a way to fool
    Napster into thinking that it is uploading an MP3 by embedding the correct
    information within the file.
    
    Any thoughts??
    
    Regards,
    
    James Rowley
    Webevent  - http://www.altern.org/webevent/webevent
    
    Web Freelancer
    WML, FLASH4, SQL, Perl, HDML, DIRECTOR 7, PHP4
    
    
    -----Original Message-----
    From: Robert Graham [mailto:robert_david_grahamat_private]
    Sent: 17 February 2000 01:22
    To: Andrew Scoggins; firewall-wizardsat_private
    Subject: Re: Killing Napster
    
    
    I looked at this a while ago. It appears that clients create an outgoing
    connection to the directory server. If the client is behind a firewall (no
    inbound connections) but somebody wants to download a file from your
    machine,
    then the Napster directory server tells you (across the control connection)
    to
    contact that user and send him the file.
    
    The upshot is that if only one of you is behind a firewall, you can exchange
    files. If BOTH of you are behind firewalls, you can't.
    
    In any case, Napster is a social protocol. It's key feature is not that it
    can
    download MP3s (FTP and HTTP can do that), but forces the user (with near
    Nazi
    tactics) to provide files for upload. Consequently, it improves the
    signal/noise ratio for users wanting to download files.
    
    Now that people have published the protocol, it will only be a matter of
    time
    before someone creates a version of Napster without the draconian publishing
    requirements. This will ultimately destroy the Napster community, as people
    stop sharing files. But, either Napster or some other program will rise in
    its
    place with a more private protocol. After September, it may even use
    RSA/SSL,
    which will begin to make our lives much harder.
    
    Anyway, blocking outgoing TCP connections to port 6699 (napster directory
    server) should fix the problem.
    
    
    --- Andrew Scoggins <scogginsat_private> wrote:
    > Hello all,
    > 
    > I am currently looking into killing the MP3 Program Napster. 
    > 
    > A user told me that he had been using it inside the firewall to download
    > files on an external Napster server. He assumed he was safe because he
    > was behind the firewall, but soon discovered that other users were
    > downloading from his machine. My guess is that Napster establishes a
    > connection from client to server that is used for uploads AND downloads.
    > So, the burning question is, has anyone blocked Napster by specifying
    > the destination port (which I haven't figured out yet) going out? I am
    > not running an application level firewall, so I can only do it by port.
    > 
    > Thanks for any help. I also post other info as I find it.
    > 
    > Andy
    > 
    > -- 
    > =-=-=-=-=-=-=-=-=-=-=-=-=-=
    >   Andy Scoggins
    >   Network Analyst
    >   Progress Software
    >   scogginsat_private
    > =-=-=-=-=-=-=-=-=-=-=-=-=-=
    > 
    >   Information security is 
    >   Y2K without the deadline.
    > 
    > 
    
    =====
    Robert Graham  http://www.robertgraham.com/pubs
    __________________________________________________
    Do You Yahoo!?
    Talk to your friends online with Yahoo! Messenger.
    http://im.yahoo.com
    



    This archive was generated by hypermail 2b30 : Fri Apr 13 2001 - 14:06:33 PDT