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- Path: sparky!uunet!zaphod.mps.ohio-state.edu!saimiri.primate.wisc.edu!news.larc.nasa.gov!grissom.larc.nasa.gov!kludge
- From: kludge@grissom.larc.nasa.gov (Scott Dorsey)
- Newsgroups: comp.security.misc
- Subject: Re: Future OS virus immunity.
- Date: 31 Dec 1992 16:35:36 GMT
- Organization: NASA Langley Research Center and Reptile Farm
- Lines: 31
- Message-ID: <1hv7goINN6sp@rave.larc.nasa.gov>
- References: <eronald.725752239@ruble> <1hv07gINN3mn@rave.larc.nasa.gov> <bontchev.725813879@fbihh>
- NNTP-Posting-Host: grissom.larc.nasa.gov
-
- In article <bontchev.725813879@fbihh> bontchev@fbihh.informatik.uni-hamburg.de writes:
- >Let's consider Unix - a typical system with memory protection,
- >discretionary access control, and all that jazz. Absolutely nothing in
- >this system prevents a virus from infecting ALL executable files of a
- >particular user. Between the different users on one and the same
- >system the virus will not spread that well, because users don't often
- >execute programs that belong to other users. An exception is the
- >"users" bin and root. Once one of those users executes an infected
- >file, the virus will spread in the system like a wildfire. But again,
- >those users do not often execute programs that belong to other
- >users...
-
- Actually, I wouldn't consider Unix to be typical either. Yes, it's
- possible for a user to infect his own personal executable, then share
- that executable with another user who then gets his own executables
- infected. True enough. But, it's not possible for them to infect
- the operating system unless one of those user executables is run by
- an account with permissions (which should never happen). The chances
- to spread are greatly reduced, and the chances of mass spread through
- the operating system are eliminated.
-
- >Between different systems the virus will have even less chance to
- >spread, because the sharing of programs occurs mainly in the form of
- >source code. You do not walk around with infected tapes and do not run
- >the programs on them on different machines, as you do in the PC world.
- >That's why, in multi-user systems the worms and the trojans are of
- >much more concern than the usual viruses.
-
- This is the case with current Unix systems, but it may not always be the
- case, unfortunately.
- --scott
-