We will examine the various ways in which virus writers have challenged our scanning products over the last decade. Although most of these techniques are used to obfuscate file-infector viruses, we can surely expect similar techniques to appear in future computer worms.
Over the years, code evolution has come a long way in binary viruses. If someone were to trace the development result of viruses, it might appear that almost everything possible has already been done, and problems are not escalating. However, there are still computing distribution models that have not yet been seen in viruses.