Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!watmath!clyde!cbatt!ihnp4!qantel!ptsfa!nonvon!apn From: apn@nonvon.UUCP (apn) Newsgroups: net.unix-wizards Subject: Re: chroot(2) security Message-ID: <113@nonvon.UUCP> Date: Sun, 28-Sep-86 17:59:33 EDT Article-I.D.: nonvon.113 Posted: Sun Sep 28 17:59:33 1986 Date-Received: Tue, 30-Sep-86 08:34:19 EDT References: <158@itcatl.UUCP> Organization: Nonvon Systems Computer Research Group Lines: 34 Summary: chroot only for su In article <158@itcatl.UUCP>, parris@itcatl.UUCP (Parris Hughes) writes: > Could some wizard out there please clue me in as to why the chroot(2) call > is only available to the super-user? I'm probably missing something here, > but I don't see any potential security problems with it. Please E-mail your > response. Thanks. > > Parris {akgua|ihnp4}!gatech!itcatl!parris Let's do an experiment: Pretend that chroot can be executed by any user, then it follows that one could do the following: cd to your home directory ( or any directory you have write permission) (we will pretend it is /mnt33/user/test) make a subdirectory called "etc" in you directory (this is now /mnt33/user/test/etc) copy /etc/passwd to /mt33/user/test/etc/passwd edit out the passwd for root write a program that changes the root directory to /mnt23/user/test and then procedes to exec /bin/login run the program and log in as the su. Get the idea ? -alex p novickis