Daxxo, a company that specializes in digital forensics, said it discovered a database that contained information on 564 million Facebook users on the social networking site. The database, which was accessible to anyone who knew its URL, contained sensitive information including email addresses, email encryption keys, usernames, Facebook tokens and birth dates, among other information.
The database, which was discovered on Monday, was found online by the security firm in the form of a Python file containing 120,000 lines of code. The file, which appeared to have been set up to be downloaded, contained the names of all Facebook users and the profile links where users could be reached.
Most of the Facebook users contained in the database were from the United States, with the most in the database from Florida, followed by California and Virginia.
Facebook has said that it is aware of the situation, but has so far not commented on the database's existence.
When asked to comment on the matter, a Facebook spokesperson wrote: "We are aware of the reports and are continuing to investigate."
In June, a data researcher who had hacked into the data of more than one billion Facebook users revealed the database, showing how the personal information of millions of Facebook users was accessible by anyone who knew its URL.
The researcher, who goes by the handle of Jester and who has previously released data from other social networks, said he accessed Facebook user data by logging into a computer that had no idea it had gained access to the site.
"The result is a database of email addresses, Facebook IDs, email addresses of Facebook friends, and the decryption key to all their posts," he wrote in a blog post.
The researcher's access to the information prompted the social network to shut down his access in order to contain the issue.
"He is now no longer able to access data or publish it on the Web, because he has broken our Terms of Service," he wrote.
"This database, which was a backup of a database dump, is not being sold or rented. This person is just sharing it online to warn the world about what Facebook's developer policy allows."New robot has the largest larynx in the animal kingdom
In 2010, the Guinness Book of World Records named the giraffe as the world's tallest living creature.
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The newest record-holder - a robotic giraffe named 3125841983
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