RE: ARP spoofing attacks

["David Gillett" <gillettdavid () fhda edu>]

  The short, sharp, general answer is that you can't.
Layer two security measures are going to see a packet
(it happens to be an ARP reply) from the miscreant's 
port, but since its source MAC address is what they 
expect, they'll let it through.  Layer three measures
won't see it either, because it's a unicast within the 
same vlan/subnet and so never needs to hit a layer 3
device.

  About all you can do proactively, if this is a serious
concern, is add a static ARP table entry to every host 
so they never need to send out an ARP request for the
gateway.

David Gillett


> -----Original Message-----
> From: Amit Agrawal [mailto:csu02103 () cse iitd ernet in]
> Sent: Tuesday, April 13, 2004 9:22 PM
> To: security-basics () securityfocus com
> Subject: ARP spoofing attacks
>
>
>
> Hi
>  I have a question...How do u secure
>  against ARP spoofing attacks...If
>  not the whole subnet...I want to be
>  sure that no one spoofs the IP of
>  my gateway.
>  
> Amit


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