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Date: Mon, 27 Oct 2003 00:02:40 -0800
From: Kris Kennaway <kris@obsecurity.org>
To: Brett Glass <brett@lariat.org>
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cc: security@freebsd.org
Subject: Re: Best way to filter "Nachi pings"?
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On Mon, Oct 27, 2003 at 12:31:46AM -0700, Brett Glass wrote:
> We're being ping-flooded by the Nachi worm, which probes subnets for
> systems to attack by sending 92-byte ping packets. Unfortunately,
> IPFW doesn't seem to have the ability to filter packets by length.
> Assuming that I stick with IPFW, what's the best way to stem the
> tide?

Block all ping packets?  Most security-conscious admins do this
anyway.

Kris

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