Re: SSH brute force blocking tool

["J. Oquendo" <sil () infiltrated net>]

Tavis Ormandy wrote:
> On Mon, Nov 27, 2006 at 04:21:19PM -0500, gabriel rosenkoetter wrote:
>   
> > Mea culpa. Tavis's exploit doesn't so scary things, although he's
> > right you should really be doing a bit more sanitization of (evil)
> > user-supplied input, given that you're (insisting that you) run as
> > root.
> >     
>
> Gabriel, I was referring to this line:
>
> awk '!/#/ && /\./ && !a[$0]++
> {print "iptables -A INPUT -s "$1" -i eth0 -d '$ifaddr' -p TCP --dport 22
> -j REJECT"}' /etc/hosts.deny |\
> awk '/iptables/ && !/#/ && !/-s  -i/'|sh
>
> (note the |sh), $1 can be controlled by specially crafted attempted
> logins.
>
> Thanks, Tavis.
>
>   

That specially crafted attempt would be a HUGE raping of TCP/IP. How do 
you supposed it would be possible for someone to insert 0wn3ed or any 
other variable outside of an IP address?

--
====================================================
J. Oquendo
http://pgp.mit.edu:11371/pks/lookup?op=get&search=0x1383A743
sil . infiltrated @ net http://www.infiltrated.net 

The happiness of society is the end of government.
John Adams

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