Subject: Re: simple tpe implementation
To: None <tech-security@netbsd.org>
From: Travis H. <travis+ml-tech-security-netbsd@subspacefield.org>
List: tech-security
Date: 02/27/2007 02:09:00
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On Fri, Feb 02, 2007 at 06:54:59PM +0100, Quentin Garnier wrote:
> I've already notified elad about that, but in case anyone would start
> using it, that implementation of TPE is actually too simple to prevent
> execution of user-supplied code.

A while back I was considering a change to the shell that would allow
you to specify a userlist that you trusted, and to ignore any programs
in your path that could be modified by anyone else.  This was back when
there was still a "bin" user, and such.  Anyway, to be thorough you
need to check the parents of each of the directories (all the way up to
the root) for writability, among other things.

--=20
Good code works.  Great code can't fail. -><-
<URL:http://www.subspacefield.org/~travis/>
For a good time on my UBE blacklist, email john@subspacefield.org.

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