Microsoft’s seventh annual Security Intelligence Report has revealed that worm infections in the enterprise rose nearly 100% during the first half of 2009 compared to the preceding six months.
Redmond identified Conficker as the most prevalent worm detected in the enterprise, primarily because its method of propagation works more effectively within a firewalled network environment, Microsoft said.
Consumers are not at great risk from Conficker because they are much more likely to have automatic updating enabled, said Microsoft.
Despite the rise in worm attacks, the biggest threat category according to Microsoft is from rogue security software, known as scareware. Scareware works by informing the user that they have a virus on their machine and tricking them into paying for software to get rid of it, which turns out to be infected with more malware.
However, Microsoft detected that 20% fewer customers were affected by rogue infections during the past six months.
Also on the decrease was the threat from the Zlob family of Trojans, which found its way onto PCs after being hidden in fake anti-malware software. Disinfections of this scareware fell from a high of 21.1 million in 2007 to just 2.3 million during the first six months of this year. Microsoft says this is evidence that the battle against Zlob is being won.
This year’s Security Intelligence Report also features best practice guidelines from countries where malware seems to be a much smaller problem. Japan, for example, runs the Cyber Clean Center, which is a collaborative project between ISPs, major security vendors and the government to educate users about PC security.
Information contained in the report was gathered through a number of reporting mechanisms, including users of Microsoft’s Malicious Software Removal Tool, which runs on 450 million PCs across the world; its search engine Bing, which scanned billions of web pages during the time period; Windows Live OneCare and Windows Defender, running on more than 100 million PCs worldwide; Forefront Online Protection for Exchange, which scans billions of emails every year; and Hotmail, which has hundreds of millions of active users.