Subject: Re: Ye Old Time Sharing System
From: rpw3@rpw3.org (Rob Warnock)
Date: Thu, 25 Mar 2004 05:53:13 -0600
Newsgroups: comp.lang.lisp
Message-ID: <MPOdnZFoOdq0Vf_dRVn-sQ@speakeasy.net>
David Steuber  <david.steuber@verizon.net> wrote:
+---------------
| Another poster mentioned security as an issue.  Is it really a big deal?
+---------------

Yes.

+---------------
| Assuming the user trusts the application server...
+---------------

That's a *huge* assumption! What if the application server is hosting
applications written by others? What if some applications (e.g., really
cute games or dancing hipmunks, etc.) are Trojan Horsess?  What if...

+---------------
| ...and the X11 protocol is being tunneled via SSH...
+---------------

It's the application server (X client) end that's vulnerable. When "sshd"
opens the listening socket on the remote end, it can't stop *any* process
from connecting to it and getting a new tunnel to your X server. The only
recourse in that case is to use MIT-MAGIC-COOKIE-1 authentication or similar,
but that requires that that owner of the X server distribute auth cookies
to *every* application server it might want to receive X connections from.
(*Ugh!*)

+---------------
| ...or RSH (can RSH do that?)
+---------------

Nope, sorry.


-Rob

-----
Rob Warnock			<rpw3@rpw3.org>
627 26th Avenue			<URL:http://rpw3.org/>
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