From: Jason Opperisano <opie@817west.com>
To: netfilter@lists.netfilter.org
Subject: Re: RELATED ICMP packets of type 3
Date: Fri, 11 Feb 2005 10:06:36 -0500 [thread overview]
Message-ID: <20050211150635.GA2371@bender.817west.com> (raw)
In-Reply-To: <200502111757.16352.e-boogie@yandex.ru>
On Fri, Feb 11, 2005 at 05:57:16PM +0300, Mikhail Zotov wrote:
> Hello everybody,
>
> I have written an iptables script to protect a machine/LAN
> and I'd like to clarify an issue about RELATED ICMP packets
> of type 3 (actually, mostly 3/1).
>
> As far as I understand, it is safe to ACCEPT incoming
> packets of this sort.
yes. personally (for whatever that is worth), i allow ICMP Types 3, 11,
and 12 [*].
> Is it safe to allow _outgoing_ packets of this kind?
> Can an attacker make my machine generate such packets
> in order to obtain information about it? (All new
> incoming packets are just DROPped.)
yes. an open plea to all firewall administrators:
please stop breaking our Internet!!!
-j
* http://www.iana.org/assignments/icmp-parameters
--
"You couldn't fool your mother on the foolingest day of your life if
you had an electrified fooling machine."
--The Simpsons
next prev parent reply other threads:[~2005-02-11 15:06 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2005-02-11 14:57 RELATED ICMP packets of type 3 Mikhail Zotov
2005-02-11 15:06 ` Jason Opperisano [this message]
2005-02-11 15:34 ` [OBORONA-SPAM] " Mikhail Zotov
2005-02-11 15:41 ` Victor Julien
2005-02-11 15:49 ` Jason Opperisano
2005-02-11 16:02 ` Cedric Blancher
2005-02-11 15:58 ` Jason Opperisano
2005-02-11 16:08 ` Victor Julien
2005-02-11 16:21 ` Cedric Blancher
2005-02-11 15:27 ` Cedric Blancher
2005-02-11 15:44 ` Mikhail Zotov
2005-02-11 15:58 ` Cedric Blancher
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