From mboxrd@z Thu Jan  1 00:00:00 1970
From: Pasi =?iso-8859-1?Q?K=E4rkk=E4inen?= <pasik@iki.fi>
Subject: Re: Protecting against DoS
Date: Tue, 9 Dec 2003 18:51:46 +0200
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To: Michael Gale <mgale@utilitran.com>
Cc: netfilter@lists.netfilter.org

On Tue, Dec 09, 2003 at 09:40:47AM -0700, Michael Gale wrote:
> Hello,
>=20
> 	Can you provide more detail on the type of traffic that caused the DOS -=
- this may help people in the list with suggestions on how to block it :)
>=20

Yep. It was tcp-connections from the windows box (infected by the worm) to
some network-ranges on the internet. source-port was pretty much random, but
the destination was always 80. So the normal 'allow web browsing' rules
allowed the worm to DoS the linux-firewall. =20

It just opened the connections all the time, but didn't close them.=20

> Michael.
>=20

-- Pasi K=E4rkk=E4inen
      =20
                                   ^
                                .     .
                                 Linux
                              /    -    \
                             Choice.of.the
                           .Next.Generation.