Do you share your personal info with everyone on Facebook? If so, there’s a decent chance that data is now part of a file — containing information for around 100 million users of the social networking site — that’s now making its way around the Web.

The file was compiled by a security consultant who wanted to show how easy it was to harvest all the information from Facebook users who hadn’t made their profiles private. The info contained in the file does not include phone numbers, e-mail or postal addresses, though it’s conceivable that this information could be just as easily harvested.

Facebook poo-pooed the news, saying that the information on the shared file is already publicly available:

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.

While it is true that all the information in the file is readily available because those users didn’t make their profiles private, a privacy expert complains to the BBC that the massive size of this data harvest shows that many Facebook users don’t understand their privacy settings:

It is inconceivable that a firm with hundreds of engineers couldn’t have imagined a trawl of this magnitude and there’s an argument to be heard that Facebook have acted with negligence… People did not understand the privacy settings and this is the result.

Details of 100m Facebook users collected and published [BBC]

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