Bugtraq: Re: ICMP spoofed source tunneling

[Tim Newsham <newsham () lava net>]

> On Tue, Sep 21, 2004 at 08:55:04PM +0400, Max Tulyev wrote:
> > Let's imagine in Net a hacker having his source server(S), destination
> > server(D), and a ip-capable device - victim(V). S sends to V spoofed ICMP
> > echo request packet containing IP source address of D, and the data in
> > Payload.
> >
> > When V receiving that packet, it sends ICMP echo-reply packet to D, AND
> > FORWARDS TO D ALL DATA IN PAYLOAD!
> This could also be used by peer-to-peer networks to achieve sender
> anonymity. (Of course you could also directly send UDP packets with forged
> source addresses...)
How does this give anonymity?  When sending to the server, I must
use the servers address as a source address.  When the server replies
to me, it must use my address as a source address.  Maybe the two
addresses dont appear in the same packet at the same time, but they're
there.  This might fool a few people when used a few times, but it
will hardly fool everyone when it is in widespread use.

Tim N.