Re: Avoiding tunnels

[Ansgar -59cobalt- Wiechers <bugtraq () planetcobalt net>]

On 2006-02-28 Javier Hijas wrote:
>   I wonder if there is a way to avoid tunnels via fw (v.g. netfilter).
> How can I control that an opened port 80 is not used to tunel to a ssh
> server listening at port 80?

You need to filter on layer 7 instead of layer 3/4, e.g. by proxying the
traffic.

Regards
Ansgar Wiechers
-- 
"All vulnerabilities deserve a public fear period prior to patches
becoming available."
--Jason Coombs on Bugtraq

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