The art of computer virus research and Defense by Peter Szor
I was in Cambridge public library when I noticed this book, and I’m glad I took it out. Funnily enough, it also mentioned John H Conway, with reference to self-replicating structures, in the early chapters. The book covers all kinds of details about virus writing, propagation and detection with lots of details with a fair bit of x86 assembler on display. For example, there are many diagrams of the buffer overflow and format string attacks against the stack of a machine, and the book lists many methods that virus writers use to make their code undebuggable. It covers techniques for cloaking the virus inside executable files, and covers propagation across a network.
A really interesting book, with perhaps a little too much information on DOS virus code.