Re: open proxy

From: Mel <rockchick(at)totalise.co.uk>
Date: Mon Mar 31 2003 - 13:12:09 EST

I'm not familiar with Domino so configuration may be different, but when you set up your mail server, were you not prompted to enter details about relay hosts and relay targets? - ie. specifying which IP address(es) the mail server should receive mail from (usually ONLY your firewall) and which IP addresses it can send mail to (this can be any, or you can specify domains to which email should not be sent).

Blocking open ports will not necessarily stop your mail server being an open relay. Obviously the machine should be locked down anyway and have only port 25 open to decrease the chance of it being attacked, but you need to lock it down in its configuration. At the moment it sounds like it's accepting and routing on mail from any IP address, and thereby probably being used by hundreds of spammers who will be spoofing their IP address using yours instead, and getting your organisation blacklisted.

Here are some links for you to check out:

http://www.ordb.org/http://www.abuse.net/relay.htmlhttp://mail-abuse.org/rbl/relay.htmlhttp://www.openrelaycheck.com/

At 12:31 PM 3/30/2003 +0200, Joost Ernest wrote:
>Hello all,

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