"While the majority of malware attacks stick to tried and true methods, malware authors are getting better at being stealthy and finding ways to fight back against the security pros trying to thwart them. A well-known example of this is the Conficker worm disabling anti-virus updates by blocking infected computers from accessing the Web sites of security companies like Symantec.
Looking ahead, several security pros said they expect some of the defensive mechanisms of today’s malware to be refined and enhanced as cyber-criminals try to sneak past researchers and network defenses alike. Right now for example, there are malicious programs capable of recognizing when they are being run in a virtual environment. By exploiting bugs in commonly used virtualization software, malware could potentially infect researchers as they begin their poking and prodding, noted Danny Quist, CEO of Offensive Computing." – Content courtesy of Malware Defensive Techniques Will Evolve as Security Arms Race Continues