Cyber-attacks on social networks are expected to increase this year. With more than 800 million members, Facebook has already been targeted many times and that's expected to continue in 2012. Other social media won't be immune from attacks in which cyber-criminals hijack profiles and use them as a channel to trick friends and acquaintances on a social network to click on a malicious link. Facebook was home last year to some of the highest profile attacks on social media. A Danish security company in November reported malware that used a picture sent from a hijacked account to get people to click on a link that installed malware capable of stealing online banking passwords. Fortunately, the so-called Zeus Trojan was first discovered in 2007, so people with up-to-date anti-virus software were likely protected.