Understanding Windows Shellcode

The purpose of this document is to familiarize or refresh the reader with the techniques used to write reliable shellcode for Windows. The reader is expected to be familiar with IA32 assembly on at least a conceptual level. It is also recommended that the reader take some time to review some of the items in the bibliography. Aside from that, the only other requirement is the desire to learn. Many portions of this document have been covered elsewhere before but, to the author’s satisfaction, have not been compiled into an easily understandable format for beginners and tinkerers alike. For this reason the author hopes that the reader walks away with a more centralized point of reference with regards to the topic of Windows shellcode. This document will focus both on Windows 9x and Windows NT based versions with more emphasis on the latter.