Companies are becoming more vigilant when it comes to their employees' use of social networking sites, according to Webroot.

The survey of more than 1,000 businesses from the U.S. and U.K. with up to 500 employees found most (81 percent) have an employee Internet policy. Half (50 percent) say employees are not permitted to visit any social networks via a company computer or laptop.

"Clearly the potential impact of social networks as a threat vector has hit home for IT administrators," said Gerhard Eschelbeck, CTO of Webroot. "One in six of those we surveyed said a social networking site or Web 2.0 application was the source of an infection or attack and over half of companies said their network was infected with spyware this year. Every company needs to develop a policy for social networking use and should also deploy reliable Web security services for ongoing protection against zero-day threats."

More: http://www.net-security.org/secworld.php?id=10159