Penetration Testing mailing list archives

Re: Tool to find hidden web proxy server


From: Rogan Dawes <discard () dawes za net>
Date: Thu, 02 Sep 2004 09:08:55 +0200

vinay mangal wrote:

Dear all,

Thanks for your suggestions. May be I am not able to define my question
properly.

This problem is strictly with in company internet access firewall and in the
LAN only. In a company, policy for Internet access says it is through IP
only. The others can not browse the internet. This policy is implemented on
firewall. Few smart guys have installed free proxy server running on non
default ports and distributed the internet access to their friends. The
firewall sees the traffic coming from the authorized IP and does not stop
them. We want to know who has installed proxy on there machine.

I hope, I am able to clearly define my question. Thanks


vinay

In that case, you should be looking for traffic destined for a proxy server in your network.

e.g.
ngrep "HTTP/1" dst net yournetwork

or something similar.

Of course, if your network is switched, you will not see the traffic you need unless your sniffer is attached to a mirrored port on your switch.

My recommendation is to have the security policy redistributed (if it already contains such prohibitions) or updated, and then point out to all your users that contravention of the security policy is a firing offence.

Your best bet to identify violators is to use (a variation of) the ngrep mentioned above, but make sure that you are seeing the necessary traffic via the switched port.

Hope this helps.

Rogan
--
Rogan Dawes

*ALL* messages to discard () dawes za net will be dropped, and added
to my blacklist. Please respond to "lists AT dawes DOT za DOT net"

------------------------------------------------------------------------------
Ethical Hacking at the InfoSec Institute. All of our class sizes are
guaranteed to be 12 students or less to facilitate one-on-one interaction
with one of our expert instructors. Check out our Advanced Hacking course,
learn to write exploits and attack security infrastructure. Attend a course
taught by an expert instructor with years of in-the-field pen testing
experience in our state of the art hacking lab. Master the skills of an
Ethical Hacker to better assess the security of your organization.

http://www.infosecinstitute.com/courses/ethical_hacking_training.html
-------------------------------------------------------------------------------


Current thread: