Subject: Re: SetUID scripts
To: Charles M. Hannum <mycroft@mit.edu>
From: Peter Galbavy <peter@wonderland.org>
List: netbsd-help
Date: 07/03/1996 08:15:54
> > How does NetBSD handle SetUID scripts?  It looks like it just ignores the
> > setuid bits (which is good).  I know some OS's have secure scripts, but what
> > about NetBSD?  I thought I remembered seeing an option for it in the kernal
> > config file, but now I can't find it anywhere (maybe it was in 1.0).  
> 
> There's a kernel compilation option called `SETUIDSCRIPTS' that
> enables the use of setuid scripts by opening the file and passing a
> `/dev/fd/N' argument to the shell in place of the original file name.
> Note that this breaks $0.

On this topic, now that the problem is well known, could somebody explain
to me in very small words what the well known security problem with set UID
scripts is ? I never grasped it. Mea culpa.

(I am one of those people, that while understanding most of this industry,
cannot quickly grasp the holes presented by race conditions - call me
stupid if need be)

Regards,
-- 
Peter Galbavy                                           peter@wonderland.org
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