Facebook has publicly revealed personal information about its members – and this could be useful to identity thieves.
Sophos says that, earlier this week, the full dates of birth of many of Facebook's 80-million active users were visible to others, even if the individual member had requested that the information remained confidential.
According to Graham Cluley, senior technology consultant at Sophos, a security slip-up by the website during the process of a public beta test of its new design for members' profiles, left birth date information exposed.
Sophos has published the following video on its YouTube channel, demonstrating the security hole: http://www.youtube.com/watch?v=jUY2UdSfL7s.
"I was shocked to see people's full date of birth revealed, even though I knew they had their privacy set up correctly to supposedly hide the information," says Cluley. "It's essential that users of social networks should have confidence that their privacy will be protected – and it's especially important with information like your date of birth, which can be a golden nugget for a committed identity thief."
Cluley says he informed Facebook as soon as he discovered the flaw, which now appears to have been fixed.
"It's good that Facebook fixed the problem – but can people feel confident that this kind of mistake won't happen again in future?" he asks. "My advice to Facebook users would be, even if your date of birth is set to be non-visible, change it to a made-up date in case this kind of blunder happens again.
"Facebook and other social networking websites need to be more careful about protecting their members' data, or risk losing users."
Sophos recommends that dates of birth on Facebook should not just be hidden, but also fictional.
Sophos notes that birth dates were exposed via the new design that Facebook is trialling for its personal user profile pages, which currently can be accessed via www.new.facebook.com. According to the Facebook developer's blog, Facebook will start rolling out the new profile page design to users this week.
Last year, Sophos published results of a identity theft probe into Facebook which uncovered that 41% of users, more than two in five, would divulge personal information – such as email address, date of birth and phone number – to a complete stranger.