Hi Rick
 RC> They are simply viruses, not trojans.  When they execute, they check
 RC> the date or time, or whatever for the "trigger" they are programmed
 RC> to use.  They then either execute the "payload" or not.  That's not a
 RC> trojan.
I see.
 RC> altogether from a "logic bomb".  There's no need to keep a user
 RC> "busy" while destroying his system, BTW.  That can be done with a
 RC> handful of instructions which execute in less than a second.
Yeah, I heard of these Trojans or bombs that only take
less than a second to partly format you hard drives,
it formats the center or something.
 cc> With money, man power and research, I thing that 99% of
 cc> possibilities are possible.
 RC> All "possibilities" are "possible", by definition.  Other things are
 RC> _not_ possible - no matter how much money you care to throw at it.
 RC> There is no need to make programs "virus proof" when this can be
 RC> accomplished by proper design of the operating system, and a
 RC> conscientious applied security policy.  As long as the OS allows
 RC> access to low-level structures _no_ program can be "protected" as you
 RC> are suggesting.
You are going to look back in 20 years time, when they
have invented a virus proof file and then think of what
I have typed about files not getting infected, and then
you will realize that nothing is impossible :)
 CC> Then people would have to resort to programming bombs, instead
 CC> of viruses.
 RC> They don't _have_ to resort to anything.
 CC> They are undetectible aren't they?
 RC> No, they're not.  But you'll have to define the term.
Program Bomb or a Batch bomb, are very hard to find,
how many scanners do you know which will check you
computer for bombs, I know of one, the ANSICHEK
series! Version 9.0, it finds hidden ANSI codes which
COULD redefine your keyboard to format your hard drive,
But is only for ANSI.
And also how many people bother scanning for bombs,
you can really get someone of there guard, especialy
if you disguised a bomb in a BBS advertisement file.
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Regards  - CC -                         v
                          MailiUg AustTalia WidE 97!
CYA..
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