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Re: Sony: No firewall and no patches


From: phocean <0x90 () phocean net>
Date: Wed, 11 May 2011 19:09:00 +0200

Le mercredi 11 mai 2011 à 16:49 +0000, Dobbins, Roland a écrit :
On May 11, 2011, at 10:03 PM, phocean wrote:

 - DDoS : anyway, a firewall isn't more susceptible to DoS than the server it protects. If you look at the hardware 
performance of modern 
firewalls, if an attacker has the ability to DoS it, then only a considerable server farm that very few companies 
can afford will be able to sustain it.

My operational experience, including that acquired during my tenure working for the world's largest manufacturer of 
firewalls by units shipped, contradicts this statement.

Can you develop? I still don't see how the hell the typical web server
will handle as much traffic as one of these Checkpoint, Cisco or
whatever monsters.


 - stateless scales badly on large networks, because it requires much more complex and lengthy rules if you are 
serious with security.

This is a) untrue and b) a near non-sequitur.  In general state is much more harmful on larger networks than on 
smaller ones; and there's no correlation at all between the size of a network and the complexity of network access 
policies.

I was talking about complexity correlation between using stateful or
stateless. Maybe it does not make any difference on a frontal firewall
with a few servers behind. But on a large network with inter-vlan
filtering, it matters a lot. Believe me, this one is based on my
operational experience.


Another advantage of stateful is that there is a first sanity check of the sessions on a specialized hardware 
rather than on a generic TCP/IP 
stack of a bloated server OS.

Marketing aside, those 'sanity checks' take place in software, not in hardware; and they actually constitute a 
greatly broadened attack surface (look at the multiple vulnerability notices/patch notices for any commercial 
stateful firewall you can name, as well as for open-source stateful firewall packages).

I still trust more the network stack of a Linux/BSD/IOS dedicated box
than the one of a Windows Server. And it means a crafted packet has to
go through mixed devices.


For instance, the network stack of Windows is probably much more prone to bug/crash due to poor handling of crafted 
packets than a dedicated 
firewall (Checkpoint, Cisco, Fortinet...) may be.

Sadly, this is also not borne out by experience.  Quite the opposite, actually.

Well maybe. I have no certitude on this point, but if you have facts,
it's welcome.

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