Get the Whitepaper called Buffer Overflows: Anatomy of an Exploit. A look at how systems are exploited and why these exploits exist.
You can download it from the following link: https://packetstormsecurity.com/files/download/108549/exploit-anatomy.pdf
Source: https://packetstormsecurity.com/files/108549/Buffer-Overflows-Anatomy-Of-An-Exploit.html