Re: Possible Mail Relay or just new usages of returned mail by spammers

In article <#TFDc11oIHA.3652@xxxxxxxxxxxxxxxxxxxx>, Gregg Hill wrote:
Do you have a firewall or router in front of your SBS? Only open inbound
ports that you want to forward.

If you have a real firewall and not just a NAT router, check this thread and
open only what you need.

It is just a NAT router, not a 'real = hardware' firewall appliance. My
understanding is that ISA 2000 is our Firewall to the external world. In that
thread, you all were talking about Port 25 only being open outbound. Now I
have done enough monkeying around in ISA 2000, to know that you can set ports
to be only open one direction. My real question was "Is there an easy way,
using the ISA Management console, to open and close Port 25?" By easy, I mean
something equivalent to having the Networks Connections screen open, on one of
my multiple desktop where it is always just one double-click away, and then
clicking enable or disable the WAN connector.

Is it just the matter of disabling a particular firewall policy? Or moving it
up or down?

What is really confusing is that I have two firewall policies near the top:

8 SMTP Server Access Rule, Allow, SMTP, External,Local Host, all users.
11 SBS SMTP outbound access, Allow, SMTP, Local Host, External, all users

But when I go in and click on the SMTP protocol, click edit, click parameters,
then I see that both are port 25 and outbound, and apparently tied to source
sets and destination sets, and I can't see how to get to either of those.

There are other SMTP rules lower down, that are worrisome.

28 ISA40: Permit mail from member server,Allow,SMTP and SMTPServer!!!, Member
Server, Anywhere!!!

I think that is just letting me mail from the member server to and from client
computers. Not sure if that allows the internet cloud to come to the member
server. I will disable that rule for now; but I would like some advice on it.

--
Hollis Paul
Mukilteo, WA USA


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Relevant Pages

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