The most popular social networking site in the world – Facebook – has made it to the headlines in the past few weeks. The total number of Facebook users crossed 500 million in June and just before the celebrations could conclude the social networking site encountered a security breach – a hacker attack, to be precise.

An online security consultant named Ron Bowles used a code to scan and collect data of Facebook users who had not applied the privacy settings in the site. The list is now available for download and contains the URL of the Facebook user’s profile with name and unique ID.

Bowles clarified that his intention was to bring to light the security issues regarding the data in the site. Facebook responded to the accusation with the statement that the information was already public due to the settings chosen by each user.

"People who use Facebook own their information and have the right to share only what they want, with whom they want, and when they want. In this case, information that people have agreed to make public was collected by a single researcher and already exists in Google, Bing, other search engines, as well as on Facebook. No private data is available or has been compromised," Facebook said.

Almost 1,000 people have downloaded the list on Pirate Bay, the world's biggest file-sharing website.