Yahoo has fixed a security flaw in Flickr that allowed anyone to access personal data sent by Flickr users who invited friends to join the photo sharing service.

The web company was criticised for acting too slowly after the invitation bug was originally reported to Yahoo a couple of months ago, according to The Guardian.

Yahoo’s chief information security officer, Alex Stamos, said that the latest bug has been fixed.

"We definitely consider this class of info disclosure to be an issue worthy of addressing and we’re sorry about the initial mistake," Stamos said.

"We’ll get back to you with bounty information shortly.

"Thank you for your patience and diligence."

Yahoo initially responded by saying that the service was working properly prior to fixing the bug and sensitive data was not being made available.