In its "Security Threat Report 2011" security vendor Sophos said that there is a significant gap between reports of malware coming from social networking websites and the potential threat perceived by businesses.

According to the data for December 2010 malware from the social networking sites hit 40% of users, up from 21.2% in April 2009 and 36% in December of 2009. Phishing is also on the rise, reaching 43% of social networking users in December 2010, up from 21% in April 2009 and 30% in December 2009, the report says.

Yet, over 50% of the companies surveyed for the report allow unlimited access to Facebook, Twitter and Linked In, and 59% of businesses surveyed think that employee behavior on social networks could endanger corporate security.

Talking about Facebook's application system, the report notes that any member can write any application - possibly malicious - and install it on their page where it can spread to other users. The problem could be addressed by walling off Facebook and allowing only approved apps or granting users the ability to ban all but vetted apps from their pages.

Of those surveyed only 4.49% opposed walling off the site from any but approved apps, the report says.