Re: file transfer over outbound port 80?

[Jon Hart <warchild () spoofed org>]

On Thu, Aug 07, 2003 at 06:08:13PM -0700, Dana Epp wrote:
> I actually do this right now. I simply set my ssh daemon on port 80, and use
> scp to covertly bypass most standard firewalls. Unless they do payload
> inspection, you can normally pierce the firewall fine in this manner.
>
> ie: scp -P 80 user () corp sshd-server com:/get/some/file/ .
>
> Short of that, you could probably simply redirect a HTTPS stream on port 80,
> and use some sort of auth to your main server and upload/download via that
> protocol. A lot more work... and not as flexible as the SSH method.
>
> One thing to consider is that some firewalls may be using a transparent
> proxy, and you might only be getting through by that proxy. If this is the
> case, there is a good chance these methods will not work for you.

In cases where they do use payload inspection, give corkscrew a shot:

http://www.agroman.net/corkscrew/

hth,

-jon

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