blochowi@cat28.CS.WISC.EDU (Jason Blochowiak) (03/17/89)
In article <8903121224.aa03512@SMOKE.BRL.MIL> ALBRO@NIEHS.BITNET writes: >art100@psuvm.bitnet / alt@ecl.psu.edu wrote about the possibility of putting >a virus in machine language attached at the end of a BASIC program and >therefore invisible to the LIST command. Quite possible, but somewhere in >the program there will have to be a CALL to somewhere you didn't load any >code, which would be a dead give-away. Not really... First of all, there are plenty of legit programs that CALL ML code to do certain things for them - including CALLs to imbedded ML. Secondly, an explicit CALL statement isn't necessary - the program could POKE certain parts of itself (self-modifying code) so that the CALL statement would be created. This would all be possible without one bit of ML (but I won't mention how, for what I consider obvious reasons - if you disagree, flame me in email, not here). Jason ------------------------------------------------------------------------------ Jason Blochowiak (blochowi@garfield.cs.wisc.edu) "Not your average iconoclast..." ------------------------------------------------------------------------------