Some six million phone numbers and e-mail addresses belonging to Facebook (News - Alert) users likely were exposed to other Facebook users over the past year.

The accident was caused by a “bug” as Facebook collected data from its 1.1 billion users, news reports said.

Facebook was able to fix the bug within 24 hours. On Friday, Facebook announced the glitch on a blog post.

"The practical impact of this bug is likely to be minimal since any e-mail address or phone number that was shared was shared with people who already had some of that contact information anyway, or who had some connection to one another,” Facebook said in the blog post.


Image via Shutterstock

“If a person went to download an archive of their Facebook account through our Download Your Information (DYI) tool, they may have been provided with additional e-mail addresses or telephone numbers for their contacts or people with whom they have some connection,” the blog post added. “This contact information was provided by other people on Facebook and was not necessarily accurate, but was inadvertently included with the contacts of the person using the DYI tool.”

Facebook also said an e-mail address or phone number was likely “only exposed to one person. Additionally, no other types of personal or financial information were included and only people on Facebook – not developers or advertisers – have access to the DYI tool.”

Affected users are being notified via e-mail, TMCnet reported.

There is no evidence that the bug was exploited or that there was any wrongdoing.

“It's…something we're upset and embarrassed by, and we'll work doubly hard to make sure nothing like this happens again,” Facebook said.

Not everyone was pleased with the way Facebook handled the glitch, as there was a delay in announcing it to the public. Also, security analyst Graham Cluley told The BBC how Facebook chose to release the information on a Friday before a weekend and said it appears the company was interested in "damage limitation."