Path: utzoo!attcan!uunet!lll-winken!ncis.llnl.gov!helios.ee.lbl.gov!pasteur!ucbvax!WPI.BITNET!GREYELF
From: GREYELF@WPI.BITNET
Newsgroups: comp.sys.apple
Subject: BASIC
Message-ID: <8903211600.AA26106@wpi>
Date: 21 Mar 89 16:00:19 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 19


A BASIC program is very capable of introducing a virus into a computer system,
and it need not be something as obvious as a poke statement and a bunch
of data statements.  One very old technique is to package an assembly
program with a BASIC program, and save it as a BASIC file.

This is done by writing the BASIC program, writing the assembler program,
loading the assembler program, adjusting the End Of Progam pointers,
and just saving it like a normal BASIC program.  Then the program
need only execute a call statement once.

This technique was used on the Program Line Editor program by
Beagle Brothers, however many years ago.

--
Michael J Pender Jr  Box 1942 c/o W.P.I.
greyelf@wpi.bitnet   100 Institute Rd.
greyelf@wpi.wpi.edu  Worcester, Ma 01609
I wrote SHELL, please send bug reports to me.