Facebook (NASDAQ:FB) users are facing an increased threat from a familiar menace. 
The Internet worm Koobface is making a comeback, with McAfee releasing a threat report detailing the increased prevalence of the worm during the first quarter. 
"The resurrection of Koobface reminds us that social networks continue to present a substantial opportunity for intercepting personal information," says Vincent Weafer, senior vice president of McAfee Labs.
Koobface allows Facebook accounts to be hacked and is a favorite tool of cyber gangs, reports USAToday.com. Spam has also increased markedly, with McAfee reporting the highest volume seen in the past two years. 
The information continually stolen from Facebook accounts provides spammers with more ways to concentrate their campaigns. With those lifted contacts, passwords and other private information, attacks can be targeted to specific companies. 
Koobface, first discovered in 2008, uses a clever ploy to attack users' computers. It sends a message inviting the target to click on a video, followed by another message requesting that the user click on a program to upgrade the video player as a requirement for watching the video. 
When the user clicks on the file, control of the PC is given to the attackers. Then the worm automatically sends out more viral messages of the same kind to the user's Facebook friends. 

The hacker gang behind the virus was tracked down to a group of five men in St. Petersburg, Russia, reports ZDNet.com. The group was identified following an investigation by both Facebook and cyber security researchers.
Since the scam's 2008 start, the group has raked in around $2 million a year.