Exchange 5.5 relay

From: Joe Seal (joeseal@YAHOO.COM)
Date: 12/11/01

Date:         Mon, 10 Dec 2001 22:36:21 -0800
From: Joe Seal <joeseal@YAHOO.COM>


I am trying to find out how someone managed to use my
Exchange server as a relay for sending spam. I am
running Exchange 5.5 with service pack 4.0 . The only
thing this Exchange server does is act as a relay
point for an application. This server sits behind a
firewall. I looked at the firewall ACL and found that
the external IP address had SMTP traffic open to the
world. That answers the questions as to how they
managed to get SMTP access to the server. I have since
blocked this ACL.

What I don't understand is how MS Exchange Server 5.5
allowed the traffic to pass through? I specified by
host IP in Exchange what servers where allowed to
relay mail. How did someone manage to use my Exchange
server to spam without being on the list of allowed
servers? I noticed that 10,000 e-mails were stuck in
the que and I could not delete them. I uninstalled the
"Internet Mail" connector and re-installed, but the
backed up messages were still there? What directory
are these messages stored so I can delete them from
Windows Explorer? Any information provided is greatly


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