Microsoft Says Half Of Windows Computers Have Trojans

According to data collected by Microsoft’s Windows Malicious Software Removal Tool during the first half of 2006, nearly half of the PCs using the tool were infected with a backdoor Trojan, which allows a hacker to remotely manipulate the computer. Such “zombie” machines are used in distributed denial of service attacks, and, according to the company’s Security Intelligence Report, “Attackers … are clearly concentrating a significant amount of development focus on this category of malware.” The current estimate of almost 50 percent infection for backdoor Trojans represents a decrease from last year’s estimate of 68 percent, but Ross Brown, CEO of eEye Digital Security, said that most consumers remain unaware of the problem. Meanwhile, the incidence of infection by rootkits fell during the same six-month period by 50 percent, according to Microsoft’s data.

Internet News, 26 October 2006