Login credentials of 45,000 Facebook users have been leaked out worldwide by the Ramnit malignant code which has invaded the world's No. 1 social network service. The biggest victims were users from the UK and France. The intrusion and theft were discovered by 'Seculert', a cyber threat management service.

Ramnit has created many variants ever since it was discovered in April, 2010. The research of Symantec in July 2011 estimated that Ramnit has caused 17.3% of all new software infection. Recently, it has started passing into social network from bank-theft.

Ramnit variants using stolen login-credentials, disguise as a link of friend (or acquaintance). Camouflaging as a post link, which the person involved had never put up, it prompts Facebook users to click those disguised posts as newly updated post and then the malware spread over. Cyber criminals take similar advantage of the tendency of users to user same password in various online services (Facebook, Gmail, Corporate SSL VPN, Outlook Web Access, etc).

Seculert has suggested users to change the password of Facebook and various other online services. The stolen credentials were delivered into the hands of Facebook.

As Facebook and Twitter users are increasing rapidly, now more sophisticated hackers are turning their eyes to social network worms. This social worm infection is more serious than old-style email spamming, which is usually being sent by unknown names, because usually it approaches users using 'disguised-as-friend' link.

To cope with this increasing social malwares, reportedly Facebook and Twitters have started to reinforce security systems by increasing more technicians to exterminate social worm or social spamming.