With the "fix-up smtp" command in your config, that 220 message would appear
something like this:
220 *************************************
-----Original Message-----
From: Aaron [mailto:agflem@yahoo.ca]
Sent: Tuesday, August 17, 2004 12:24 PM
Cc: firewalls@securityfocus.com
Subject: Re: SMTP Relay
telnet [ip address] 25
220 mx3.domain.com WebShield SMTP V4.5 Network Associates, Inc. Ready at Tue
Aug 17 12:29:12 2004
Exchange will show something similar ...
jamesworld@intelligencia.com wrote:
Roy,
How can one determine that it's an exchange box or any other mail server?
I do support the design of a mail gateway.
At 08:34 AM 8/17/2004, Kidder, Roy wrote:
The PIX can mask the "220" greeting from a mail server so that the
vendor and version of the mail system cannot be seen "plain text".
This is called "smtp fix-up". At best, this is security by obscurity
though. A determined individual can still determine that it's a MS
Exchange box sitting back there.
A better option is to put up a non-Exchange gateway (there are many
products out there) between your internal Exchange system and the
Internet. This gateway would be configured so that email from the
Internet comes into it, is scanned for any virus threat and content
(if desired) and then passed on to the Exchange server on the inside.
This way, the Exchange server is never actually touched by the outside
world.
Hope that helps,
Roy
-----Original Message-----
From: Aaron [<mailto:agflem@yahoo.ca>mailto:agflem@yahoo.ca]
Sent: Thursday, August 12, 2004 12:23 PM
To: jamesworld@intelligencia.com
Cc: firewalls@securityfocus.com
Subject: Re: SMTP Relay
How can I protect an IIS-SMTP service with a PIX?
jamesworld@intelligencia.com wrote:
You cannot set up the PIX as a SMTP relay as it does not have a SMTP
engine. You can use it to protect a SMTP relay (sendmail, IIS-SMTP,
3rd
party, etc) though.
SMTP services are a component of a server. The PIX is not a server.
Cheers,
-James
At 03:03 PM 8/11/2004, Aaron wrote:
Is it possible to setup a PIX for SMTP relay?
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