Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!elroy.jpl.nasa.gov!ames!sheba.arc.nasa.gov!schoch
From: schoch@trident.arc.nasa.gov (Steve Schoch)
Newsgroups: comp.windows.x
Subject: Re: Xterm cannot write log files
Message-ID: <1991Apr25.165226.24709@news.arc.nasa.gov>
Date: 25 Apr 91 16:52:26 GMT
References: <9104100652.AA06486@lightning.McRCIM.McGill.EDU> <1991Apr10.222541.14268@ux1.cso.uiuc.edu> <22173@shlump.nac.dec.com>
Sender: usenet@news.arc.nasa.gov (USENET Administration)
Organization: NASA Ames Research Center, Moffett Field, CA
Lines: 17

In article <22173@shlump.nac.dec.com>, lan_csse@netrix.nac.dec.com (CSSE LAN Test Account) writes:
|> In article <1991Apr10.222541.14268@ux1.cso.uiuc.edu> phil@ux1.cso.uiuc.edu (Phil Howard KA9WGN) writes:
|> >mouse@lightning.mcrcim.mcgill.EDU (der Mouse) writes:
|> >
|> >>> Is there any pressing reason for xterm to be suid root ?
|> >
|> >>Not unless you want utmp entries for your xterm windows.  (Unless you
|> >>make utmp world-writeable, which opens up other, fairly serious,
|> >>security holes, but that may be acceptable in trusting environments.)

There's another (bigger, in my opinion) security hole created by NOT making xterm setuid root.
When it is suid root, it changes the owner and permissions of your pty so that things like mesg,
biff, etc work.  If it is not suid root, then your pty will remain owned by root, mode 666.  This
means that anyone can write to, and read from (!) your xterm.  This can cause input you type
to go to somebody's cracking program rather than the program you are trying to run.

	Steve