With social networking sites attracting millions every month, the risk of virus attacks, account hijacks and spam mounts. Several instances of hackers exploiting these social media networks have exposed flaws in the system. In April this year, Michael Mookey, a 17-year-old student from New York, created a virus that sent automated tweets in thousands through a cross-site scripting vulnerability. Twitter acknowledged the attack but insisted that no user-sensitive data was lost. Apparently, Mookey only meant to popularise his site, stalkdaily. In August, Twitter was shut down for a few hours when a hacker sent a worm that crashed its servers. The same morning, Facebook confirmed that there was a similar attack but said it affected only a part of the network. Read the complete story on Social Media hacking and spamming.