Xref: utzoo comp.unix.wizards:25531 alt.security:2511 Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!wuarchive!zaphod.mps.ohio-state.edu!caen!uther!mjr From: mjr@uther.calvin.edu (Matt Ranney) Newsgroups: comp.unix.wizards,alt.security Subject: Re: BSD tty security, part 3: How to Fix It Message-ID: Date: 10 May 91 18:45:54 GMT References: <7299:Apr2510:22:2091@kramden.acf.nyu.edu> <12535@dog.ee.lbl.gov> <15896:Apr2714:35:3991@kramden.acf.nyu.edu> <1991May9.145536.20002@odin.diku.dk> Sender: news@engin.umich.edu (CAEN Netnews) Organization: The University of Michigan, Ann Arbor Lines: 22 I've just joined this groups a few days ago, so I missed most of the other things that were said, but the "write" program doesn't even need to be used to fire anonymous messages to people. You can just cat a core dump > their tty. I'm sure this has been said before, but could someone please enlighten me on a few things? I still don't see why tty security is such a difficult problem to resolve. Why not make programs that need to spam the user's tty setuid root, and change the default permissions on user's ttys so that only they (and root, of course) have read/write. And make the write program, as was said before, spew data at a slower rate, and prepend each line with the writer's id. The login program is already setuid root, so the permissions could stay at root r/w only. This would fix programs like "cover" from working. So why wouldn't this work? If some other naive person like myself has already asked this question and had it answered, please respond via Email. Thanks -- Matt Ranney -- t22918@ursa.calvin.edu sendmail: error reading file /home/t22918/.signature (core dumped)