Full Disclosure mailing list archives

Re: SSH brute force blocking tool


From: Tavis Ormandy <taviso () sdf lonestar org>
Date: Mon, 27 Nov 2006 21:29:33 +0000

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.

-- 
-------------------------------------
taviso () sdf lonestar org | finger me for my pgp key.
-------------------------------------------------------

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