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From: panix!alexis@cmcl2.nyu.edu (Alexis Rosen)
Newsgroups: comp.virus
Subject: Re: Viruses in Sound Effects (Mac)
Message-ID: <0005.9009251406.AA22228@ubu.cert.sei.cmu.edu>
Date: 25 Sep 90 08:30:57 GMT
Sender: Virus Discussion List <VIRUS-L@LEHIIBM1>
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Approved: krvw@sei.cmu.edu

Look, this whole discussion of nVIR in sound files is bogus. nVIR and
its variants can only *infect* applications (including Finder and DA
Handler) and the system file. Of course, it can *affect* anything.

The assertion that you should check everything is fairly decent advice
for beginners, but there are definitely many types of files that will
remain forever uninfectable. (That is, with a healthy contagious
virus.) In general, these are data files which don't contain
information which is interpreted as anything like instruction
sequences by a fairly generic command processor.  Yes, I know that
that's a pretty vague definition, but it's pretty accurate too for all
of that.

Note that this definition pretty much rules out ever having a complete
active virus in a sound file (in the formats which we generally use.
If someone were to invent a sound format that, like TrueType for
example, were to consist of data and instructions, that might just
possibly be excepted).

I wonder about how close a "command processor" has to be to a turing
machine in order to be ably to spread infectious code. Some
requirements are obvious, some are not.

Interestingly enough, this definition allows for viruses in english
text.  Of course, those viruses infect humans. Specifically, their
brains.  (Mention "memes" in sci.nanotech if you want to get flooded
with info about this...)

- ---
Alexis Rosen
cmcl2!panix!alexis