A Microsoft study performed in December 2012 indicated that 63% of sampled pirated software was being distributed with some type of malware or trojan virus. And the news gets even worse for those pirating Microsoft software where 77 percent of the Windows Update functionality had shown to be disabled or re-routed to third-party services.

The study also found that among computers with bootleg copies of Windows operating systems (OSes), 77 percent of the Windows Update functionality has been disabled or re-routed to third-party services. The software giant said these PCs with disabled Windows Update bypass genuine software checks and are denied critical security patches which causes them to be defenseless against malicious cyberattacks.

ZDNET: 3 in 5 pirated software in Southeast Asia malware-ridden