While many mass malware families follow similar patterns in order to achieve their goals, there is also a much smaller—but at the same time, often of a higher significance—set of samples implementing advanced techniques in order to achieve more specific goals. An example is APT groups performing high-profile espionage tasks and therefore having much higher requirements in terms of stealth and effectiveness. In this section, we will go through some of the most notorious examples and cover advanced techniques that have been implemented.





















































