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- Newsgroups: comp.org.eff.talk
- Path: sparky!uunet!van-bc!rsoft!mindlink!a3916
- From: Clayten_Hamacher@mindlink.bc.ca (Clayten Hamacher)
- Subject: Re: Beneficial Virus
- Organization: MIND LINK! - British Columbia, Canada
- Date: Tue, 12 Jan 1993 06:34:13 GMT
- Message-ID: <19534@mindlink.bc.ca>
- Sender: news@deep.rsoft.bc.ca (Usenet)
- Lines: 43
-
- >>One possible problem would be a malicious virus masquerading as a
- >>valid marker file. Then any file compressed with the beneficial
- >>virus would activate the malicious virus - some sort of check would
- >>have to be made that the virus was the *RIGHT* virus.
- >
- >With all the attendant troubles of verification and the slowdown it
- >will present.
-
- Do you check all the rest of the programs on your system? They are just as
- likely to have 'evil twins' lurking around.
-
- >Note that this would change the creation date of every executable
- >every time the program was run. Even on a single-user MS-DOS system,
- >this can have some undesirable results.
-
- Like what? Your half-witted virus checker goes off and shuts down the
- computer?
- In almost every OS I've ever used there has been a way to fake the
- modification
- date, in unix you just write a new date, in MS-DOS if nothing else you just
- record the current time, set the clock to the old modification date, write
- the
- file, set the clock to the time you just recorded plus about two seconds..
- And
- decent virus could do it so it's not a very good way to tell if you're
- infected.
-
- >>Having considered the infected file, let's consider the virus in operation.
- >>It is assumed that the virus has only been placed in memory after it has
- >>been verified that the marker was present, and it is okay for it to run.
- >
- >Does the virus get removed from memory after the executable stops? If not,
- >then what happens when another executable is run?
-
- You do understand the meaning of the word 'virus' don't you? If it finds the
- marker (ie it's ok to execute) then it does what the name suggests and
- infects
- the next executables that you run. If it doesn't find that permission then it
- quits operation after unpacking the program.
-
- --
-
- Clayten_Hamacher@Mindlink.bc.ca Land of the rising snow.
-