Mysterious security hole

[Alan Barclay]

In article <2007 at nixsin.UUCP> koerber.sin at sni.de writes:
>In article <1991Jun22.220635.17145 at rock.concert.net> mcmahan at cs.unca.edu (Scott McMahan) writes:
>|In article <1991Jun21.203054.989 at serval.net.wsu.edu> yeidel at tomar.accs.wsu.edu (Joshua Yeidel) writes:
>|>>The example of having something in / is bad for obvious reasons.  But 
>|>>what about /tmp?  A script named say "la" (common type of "ls") which
>|>>does a chmod 777 /, sends mail to the person and then echos 
>|>>"la: Command not found" would do the job nicely. 
>|>
>|>Is /tmp in your path?  Why?
>|
>|I wondered that myself.
>
>No, but if '.' is in your path, and you are in /tmp, that will do some damage.
>Same thing for any writable dir in your path. Maybe UNIX should have an
>option which lets one refuse to run
>	a) writable scripts/programs
>	b) setuid scripts/programs

Ah, so you don't want to run ps, mail or at, to name three programs which
are normally setuid. Also when root a lot of programs have permissions
of 7xx so almost all programs would be writable.
-- 
  Alan Barclay
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