"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," said 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."
A video demonstration of this flaw can be seen here.
At present time the flaw appears to have been fixed. However, chances are that such mistakes will happen again in the future, says Cluely. Until Facebook gets a good grip on its privacy settings, it would be advisable to replace the actual date with a fictional one:
"It’s good that Facebook fixed the problem – but can people feel confident that this kind of mistake won’t happen again in future? 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."