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Re: Netscape Logic Bomb detailed by IETF





Aleph One / [email protected]
http://underground.org/
KeyID 1024/948FD6B5 
Fingerprint EE C9 E8 AA CB AF 09 61  8C 39 EA 47 A8 6A B8 01 

On Tue, 24 Oct 1995, Dr. Frederick B. Cohen wrote:

> Date: Tue, 24 Oct 1995 05:29:33 -0400 (EDT)
> From: Dr. Frederick B. Cohen <[email protected]>
> > In message <[email protected]>, Dr. Frederick B. Cohen writes:
> > >I strongly disagree.  If Netscape provided a way to execute shell
> > >commands on your host from a remote computer, it would certainly be a
> > >hole created by their product.  The fact that the default shell is
> > >potentially dangerous means it's incumbant on those who provide access
> > >to it to provide adequate protection.
> > 
> > They do, add:
> > 
> > application/x-shell; sh %s
> > 
> > to your .mailcap.
> > 
[..rant removed..]
> To support the position you seem to be taking (and the one currently
> taken by Netscape), you would have to say that the last several Sendmail
> "bugs" were not sendmail problems but rather shell problems because all
> sendmail did was allow you to execute a shell from the remote machine
> (perhaps via a queue file).  You would also apparently say that it's
> secure to allow a server to grant unlimited shell access to unknown,
> unauthenticated remote users.  This seems foolhearty to me.

This is compleate bullshit. Equating bugs on sendmail to adding the above
to your mailcap, is compleately of the wall. Why not try this: compare it to
adding 

	stupidfuck: "|/bin/sh"

Obiously no one in their right mind will put the above on their aliases file.
And please tell me of one MTA does check for this? You want to add to 
sendmail so that it checks for this? Maybe it should also check for
pipes to perl, sed, awk, csh, python, ad nauseum.

Now if you would understand that *people* are supposed to know what to put
into their aliases file, you would understand they need to know what they 
have to put in their mailcap files. There is nothing a program can do 
about it. If you scan for certain interpreters and outlaw them, new ones 
will be created you dont know about.

Your logic is compleatly flawled.

> That's correct.  Secure software has to have secure distribution in
> order to maintain its security when distributed through an untrusted
> channel.  I think that Netscape uses an MD5 checksum which the members
> of this list seem to place unlimited trust in (incorrectly in my view,
> but that would be picking two nits with one keyboard entry).

Question: Does your software (your striped down http server, etc)
do this? I bet not.