*BSD News Article 55563


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From: toor@awfulhak.demon.co.uk (Bourne-again Superuser)
Newsgroups: comp.unix.bsd.freebsd.misc
Subject: Re: Restricted shell in FreeBSD?
Date: 27 Nov 1995 05:18:52 -0000
Organization: None
Lines: 29
Message-ID: <49bhns$dvl@awfulhak.demon.co.uk>
References: <48dc2k$aki@maui.cc.odu.edu> <48ki66$ktk@uriah.heep.sax.de> <DIAr9y.1np@thor.shn.com> <492sdj$r6g@uriah.heep.sax.de>
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J Wunsch (j@uriah.heep.sax.de) wrote:
: hw@thor.shn.com (Henning Wickhorst) writes:

: > But be very careful in trusting its secure promises. If the user's
: > PATH includes '/bin' for example, he can execute 'sh' and he has a
: > non restricted shell.

: More generally, if the user has any opportunity to create an
: executable on the system (run csh, drop a uuencoded binary, unpack a
: tar archive, compile a C program etc.), he can quickly bypass the
: restrictions.

Not if it's set up correctly.  You can't run a program by specifying the
path name, so if your path just includes non-writable directories, all of
the above will fail !

But your "point" is correct - chroot is much more secure !

: -- 
: cheers, J"org

: joerg_wunsch@uriah.heep.sax.de -- http://www.sax.de/~joerg/ -- NIC: JW11-RIPE
: Never trust an operating system you don't have sources for. ;-)


--
Brian <brian@awfulhak.demon.co.uk>
Don't _EVER_ lose your sense of humour....