A bug in the Facebook system led six million users’ contact information to be inadvertently exposed, the social media giant has said.

A bug led to some contact information – such as e-mail addresses or phone numbers – to be uploaded by other users, Facebook said.

The problem arose when users downloaded an archive of their account through Facebook’s Download Your Information tool. Because of the bug, users might have been provided with additional e-mail addresses or telephone numbers for their contacts or people with whom they have some connection.

Because the contact information was provided by other people on Facebook, it was not necessarily accurate. Facebook said it has fixed the problem and is in the process of notifying affected users by e-mail. (PA)