[Full-disclosure] VLAN Hopping, myth or reality?

[Mikael Abrahamsson]

On Mon, 19 Sep 2005, Yersinia Authors wrote:

> We haved tested this attack only against Cisco switches 29xx, so we 
> would be pleased if we received notifications of working attacks in 
> other Cisco modeles, or better, other vendors (which is almost 
> impossible since DTP is Cisco proprietary, but, we've seen HP switches 
> with CDP enabled ;) )

You will most likely be able to do this to any cisco switch that supports 
DTP. What you're doing is using a misconfiguration, not really a 
vulnerability. You're not vlan hopping, you're telling the switch that you 
are a switch and that the interlink should be in trunk mode, and then the 
other end will give you access to all vlans, if it's configured default 
from factory.

-- 
Mikael Abrahamsson    email: swmike at swm.pp.se