Re: [PEN-TEST] IP Tunneling over DNS

[Jose Nazario <jose () BIOCSERVER BIOC CWRU EDU>]

On Mon, 11 Sep 2000, Christopher M. Bergeron wrote:

> theoretically, someone from inside a secure network could tunnel out
> (ala Trojan) to punch a major hole through a firewall.  Am I
> understanding this correctly?

yes, yes you are. also, lookfor IP over SMTP tunneling. and LOKI, using
ICMP as a covert data channel.

tunneling is a major method of passing firewalls. tunnel whatever you want
through normal channels. unless the firewall is doing application level
filtering, you can really have some fun. you gotta be patient, but it can
be done.

there really isn't any reason why application level firewalls shouldn't be
more available and in wider use that i can see. they're tough to do right,
mind you, but not impossible.

jose nazario                                    jose () biochemistry cwru edu
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