Microsoft researchers pulled data from more than 600 million systems in more than 100 countries. 99 percent of all attacks in first half of 2011 distributed malware through familiar techniques like social engineering and vulnerabilities for which updates or a patch exist. Approximately 90 percent of vulnerabilities exploited had security updates or patches available for more than a year. More than a third of the detections that were analyzed were caused by malicious software that misused the AutoRun feature in Windows. About 6 percent of the MSRT detections analyzed were likely caused by exploits.”]