Security Incidents: Port 6688 Traffic

[Crist Clark <crist.clark () GLOBALSTAR COM>]

I am seeing "suspicious" traffic on port 6688. I have not found references
to this port in the ususal resources (/etc/services,
http://advice.networkice.com/advice/Exploits/Ports/,
http://www.robertgraham.com/pubs/firewall-seen.html, etc.). My very
rough analysis of the pattern and after catching some traffic leads
me to guess that this might be a Napster port, Napster-workaround
port, or something similar.

Someone recognize this protocol? This is what happens when I try to
telnet to one of these machines,

  $ telnet remote-host.at-some.cable-isp.com 6688
  Trying 24.123.45.67...
  Connected to remote-host.at-some.cable-isp.com
  Escape character is '^]'.
  1

At this point, I don't know what to say, so I type something, 'HELP,' in
this example,

  1HELP
  INVALID REQUESTConnection closed by foreign host.

Anyone familiar with this? If it is Napster or some sharing program,
fine, whatever, I am worried about malware.
--
Crist J. Clark                                Network Security Engineer
crist.clark () globalstar com                    Globalstar, L.P.
(408) 933-4387                                FAX: (408) 933-4926

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