Re: A Solution for sniffing

["Shanon" <liquid_nitrogen79 () hotmail com>]

Not only DNS, but IMO a lot things should not be run on the sniffer machine
what ever it is.

Try composing a mail and send it while some arp sniffer (MITM attack) like
ettercap is running :)) ....for me the destined recipent was spammed with
the same copy for three days :))

There are lots of white paper floating that explains how to detect if some
machine is in promiscous like
by sending an echo reply packet (arp, any query etc) to some and see how
many replies you get in return.....


----- Original Message -----
From: <Bruce.Orcutt () alltel com>
To: <SMerrell () avbpgh com>
Cc: <security-basics () securityfocus com>
Sent: Wednesday, December 18, 2002 11:15 PM
Subject: RE: A Solution for sniffing


Actually, I had never heard of Anti-Sniff before.

Looks interesting, but looks easily circumvented by a determined techie.

Anti-Sniff has three major components:

1) NT based:

Easiest way to avoid is not run Windows NT on the Sniffer :)

2) DNS:

Easy way to avoid is not to use DNS on the Sniffer, take the logs from the
Sniffer and use it to the DNS lookups desired at a later date on a later
machine.  Can easily set up a simple program to read in a table of IPs, then
convert them into DNS names, and re-write the table

3) Timing with a flood:

Don't know about your network, but I know I would not want to add the extra
traffic of a flood of packets.  Also, pretty easy to add a little
intelligence into your Sniffer that if it receives X number of packets in Y
number of seconds, shut down promiscuous mode temporarily.  Also, with
faster and faster nics coming out, more and more packets are able to be
processed, thus necessitating the increase in the size of the flood, thus
causing more problems associated with flooding a network.

Just some of my thoughts at least





-----Original Message-----
From: Merrell, Sam [mailto:SMerrell () avbpgh com]
Sent: Wednesday, December 18, 2002 12:18 PM
To: Orcutt, Bruce
Subject: RE: A Solution for sniffing


What about L0pht's Anti-sniff product?  Is that still available?




-----Original Message-----
From: Bruce.Orcutt () alltel com [mailto:Bruce.Orcutt () alltel com]
Sent: Tuesday, December 17, 2002 12:19 PM
To: fadi () lebrocks com; security-basics () securityfocus com
Subject: RE: A Solution for sniffing


As sniffing is a passive act, there is no way that you can detect the act
itself, unless you have access to the machine that's doing the possible
sniffing itself.

Perhaps one of the simplest ways to ensure sniffing is made much more
difficult at the least is by switching from a hub type network to a switched
network.  In a switched environment, other users cannot see each others
network streams, thus providing a layer of protection.

Of course, like all techniques, this can be gotten around by various
additional techniques, but it does make life more difficult to would be
sniffers. (ie: user installs a hub via an uplink port to switched segment,
and connects target's system and a sniffing machine to the hub.)



-----Original Message-----
From: fadi () lebrocks com [mailto:fadi () lebrocks com]
Sent: Tuesday, December 17, 2002 5:41 AM
To: security-basics () securityfocus com
Subject: A Solution for sniffing



Hello Folks,
I think i am being sniffed by somone on my network, and i was wondering. is
there an application to check wether i am being sniffed or not, and if i
was, how can i fix that ?(like PGP for mail, what about other protocols)

P.S. : Running Linux Slackware 8.1 (if that would help)

cheers,
Fadi R. Khouja

---
Incoming mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.431 / Virus Database: 242 - Release Date: 12/17/2002


---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.431 / Virus Database: 242 - Release Date: 12/17/2002