In this paper the author describes AV methods and focuses on how to fool antivirus emulation systems. They set themselves a challenge to find half a dozen ways to bypass AV dynamic analysis by using a fully undetectable decryption stub.
You can download it from the following link: https://packetstormsecurity.com/files/download/127993/BypassAVDynamics.pdf
Source: https://packetstormsecurity.com/files/127993/Bypass-Antivirus-Dynamic-Analysis.html