RE: Which ports to block?

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To: "'Ferino Mardo'" <RMardo@ALJOMAIHBEV.com>, <security-basics@securityfocus.com>
Date: Mon, 26 Jul 2004 11:42:42 -0800

It's safest to block thru 65535. There are many services that run above
1023 and these would be allowed through the firewall if you don't block
them (depending on the firewall and implementation). Remember just
because they're not 'well-known' doesn't mean that they're not
well-known. ;-)

Ed Spencer
MCSE/MCT/MCP/CNA/A+/Network+/Security+
Network Administrator
Aramark Corporation
Denali National Park.

-----Original Message-----
From: Ferino Mardo [mailto:RMardo@ALJOMAIHBEV.com]
Sent: Saturday, July 24, 2004 12:04 AM
To: security-basics@securityfocus.com
Subject: Which ports to block?

In setting up a "deny all" rule from a firewall, is it safe to block
ports 0 to 65535 or only up to 1023? My interest are only to allow port
53 udp, 25, and 80.

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• Previous message: Ryan Murphy: "Outsourced IDS and Firewall--MSSPs..."
• In reply to: Ferino Mardo: "Which ports to block?"
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