Re: IP Spoofing with DHCP ?

[Alon Oz <alon () LINUXQA COM>]

Skreel wrote:

> Hi I have a question concerning the DHCP protocol. I've heard that
> this protocol could allow a user to choose he's own IP address if it
> isn't already assigned to another user. I was wondering if a network
> using DHCP to assign IP addresses and authenticating users upon
> their IP address could lead to a breach (i know authentication upon
> IP address has never been a good security) but in theory would it be
> possible for an attacant to DoS a user's box and then spoof his IP
> before the ping timeout in order to be authentified as the user ?
>
> Thanks for the help

Security on the local network can never be tight, the idea is to secure
your network from the outside world,
usually if an intruder gained access to one computer on your local
network he can (sooner or later) gain access to every computer on it.
so as an answer to your question, Yes, DHCP could be used in order to
gain unauthorized access, but most of
the other services people use on the local network can too.


--
Alon Oz,
Aduva Research Team,
Mailto: alon () linuxqa com

Trust in Allah, but tie your camel.
                -- Arabian proverb