Cyber fraudsters targetted users of social networking site Facebook with a range of 'friend request' emails to draw them into downloading a banking Trojan, says a report by IT company Cyberoam.

"Malware authors and scammers of today are well acquainted with the behavioural psychology of Facebook users.

Many of them are intelligent but won't think twice before accepting a friend request from someone they don't know," said Abhilash Sonwane, Senior VP, Product Management, Cyberoam, while releasing October 2011 Internet threats trend report.

Cyberoam conducted this study in partnership with IT security solution company Commtouch.

"Facebook continues to draw the attention of malware authors. An August attack used a range of 'friend request' emails to draw recipients to a download of a banking Trojan," the report said.

The company also noticed people getting lured by 'Free' offers on Facebook which led them to spread spam to their friends as well. The study found an ubiquitous Facebook 'like' button harnessed by advertising scammers to lure users into receiving free merchandise like iPhone 4.

Those wanting to receive the 'free' merchandise were asked to like several pages, provide their shipping addresses and forward the invite on to 100 or so friends thus ensuring the spread of the scam. The pages were liked by hundreds of thousands of Facebook users, the report said.