It seems, however, that this is not the last twist. Recently, our research lab identified a completely new 'financial' Ramnit variant aimed at stealing Facebook login credentials. Since the Ramnit Facebook C&C URL is visible and accessible it was fairly straightforward to detect that over 45,000 Facebook login credentials have been stolen worldwide, mostly from users in the United Kingdom and France.
We suspect that the attackers behind Ramnit are using the stolen credentials to log-in to victims' Facebook accounts and to transmit malicious links to their friends, thereby magnifying the malware's spread even further. In addition, cybercriminals are taking advantage of the fact that users tend to use the same password in various web-based services (Facebook, Gmail, Corporate SSL VPN, Outlook Web Access, etc.) to gain remote access to corporate networks.
With the recent ZeuS Facebook worm and this latest Ramnit variant, it appears that sophisticated hackers are now experimenting with replacing the old-school email worms with more up-to-date social network worms.