Subject: Re: OT: - help needed
To: Shannon <>
From: Greg A. Woods <>
List: netbsd-users
Date: 01/28/2002 21:25:22
[ On Monday, January 28, 2002 at 12:05:36 (-0500), Shannon wrote: ]
> Subject: Re: OT: - help needed
> The problem here is that it's possible to have open relays on your
> domain, and you don't have control over that machine. Should you be
> blacklisted in that case? I don't know if Orbz would blacklist in that
> case, but some people have. A company I worked for was blacklisted
> because a customer's machine had an open relay. As I recall, it was
> difficult for us to reverse the situation, and lawyers were involved.

The company you worked at ran an open relay.  Even if it was not an open
relay on its own, it was still vulnerable to theft of service attacks.
Some people call this a multi-level open relay, but from the spammed
person's perspective such distinctions are irrelevant.  Spam gets
through them just as well, and sometimes even better, than it will
through a "stand-alone" open relay.  Of course from the spammer's point
of view such multi-level open relays are merely new opportunities to
exploit, and it seems commonly available spamware now makes use of them.

There are many ways the company you worked for could have avoided their
mailer becoming an open relay.  Which method would have been best for
them to implement depends on many factors you don't discuss.  Since you
mention a legal dispute it would seem the company was naive in entering
an agreement without fully understanding the consequences.  If people
blocked their SMTP connections as a result then they were simply
learning and paying the costs of their mistake.  If spammers actually
exploited their vulnerability then they paid even more for their

								Greg A. Woods

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