Bugtraq: Re: Three possible DoS attacks against some IOS versions.

[Felix Lindner <felix.lindner () nruns com>]

Sharad Ahlawat wrote:
> an excerpt form RFC 2281 - Cisco HSRP
>
> 7. Security Considerations
[SNIP]
>  It is difficult to subvert the protocol from outside the
>  LAN as most routers will not forward packets addressed to the
>  all-routers multicast address (224.0.0.2).
This does not prevent remote attacks because Cisco devices do not
validate the destination address of a HSRP packet. Unicast packets are
accepted, which can be tested using the hrsp tool at
http://www.phenoelit.de/irpas/ 

Regards
/F