Re: [FW-1] Filtering incoming SMTP "from" your domain via SS

Subject: Re: [FW-1] Filtering incoming SMTP "from" your domain via SS

From: Dan Hitchcock <[email protected]>

Date: Tue, 4 Jun 2002 10:53:11 -0700

Reply-to: Mailing list for discussion of Firewall-1 <[email protected]>

Sender: Mailing list for discussion of Firewall-1 <[email protected]>

Title: Filtering incoming SMTP "from" your domain via SS

Sure. Just specify a resource with *@foxboro.com as the source, * as the destination, and make the action "drop" in the rulebase.

HTH

Dan Hitchcock
CCNP, CCSE, MCSE
Security Operations Technical Lead
Breakwater Security Associates, Inc.
"Safe Harbor for Your Business"
dhitchcock (at) breakwatersecurity (dot) com
http://www.breakwatersecurity.com
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-----Original Message-----
From: Coleman, Clayton [mailto:[email protected]]
Sent: Tuesday, June 04, 2002 8:20 AM
To: [email protected]
Subject: [FW-1] Filtering incoming SMTP "from" your domain via SS

Here's the scenario: We block all incoming mail not destined for our mail domains (to block relay) but we are also considering not allowing people to deliver mail to us that appear to come from our domain. Confusing?

Simply put, should we allow someone from the Internet to deliver to our SMTP server "From: [email protected]" "To: [email protected]" since all mail from foxboro.com should come from internal? What would be the downsides of blocking someone from the Internet who tries to do that?

And, can we do that in a resource...? I only think it works for the destination domain, not the source domain of the email.

Thanks much.

Clayton