50% infected:
Of the 4 million computers cleaned by the company's MSRT (malicious software removal tool), about 50 percent (2 million) contained at least one backdoor Trojan.
Rootkits down:
Despite increased industry interest in Windows rootkits in 2005, Microsoft found a surprising 50 percent reduction in the attacks, which employ stealthy tricks to maintain an undetectable presence on infected computers.
Mass mailing worms common:
Not so surprising is the data surrounding malware that employs social engineering tactics, especially those that lure targets via e-mail or P2P (peer-to-peer) networks. "For example, in the case of both the MSRT and Microsoft Windows OneCare, approximately 20 percent of computers cleaned were infected with a mass-mailing worm," Microsoft explained.
Turkish computers disproportionately affected:
Data collected by the MSRT suggests that computers that use certain languages are more likely to be infected with malicious software than others. For example, when the disinfection figures from an operating system language are normalized with the appropriate number of tool executions of that same language, Microsoft found that 16 percent of computers cleaned by the MSRT are from Turkish language computers.
New variants of backdoor Trojans maintain bot networks:
Backdoor Trojans: The first half of 2006 showed a significant number of new backdoor Trojans. A large number of those belong to bot families, such as Win32/Rbot and Win32/Sdbot. This trend is consistent with anecdotal industry knowledge; owners of bot networks are continually creating and delivering new variants of their bots to maintain their bot networks, and to evade detection by anti-malware products.
EDIT: Forgot the link for this one:
