A Facebook bug that was live for four days in May set millions of users’ default sharing settings to public, the company revealed on Thursday.

Facebook said it would be notifying the 14 million users who had posted publicly between May 18 and 22.

“We recently found a bug that automatically suggested posting publicly when some people were creating their Facebook posts,” Erin Egan, Facebook’s chief privacy officer, said in a statement.

ADVERTISEMENT

“We have fixed this issue and starting today we are letting everyone affected know and asking them to review any posts they made during that time,” Egan said. “To be clear, this bug did not impact anything people had posted before — and they could still choose their audience just as they always have. We’d like to apologize for this mistake.”

Affected users will see an alert in their notifications about the error and will be able to review the posts that went public.

Facebook said that while it was able to stop the bug on May 22, it couldn’t switch all of the posts to private until May 28.

The bug was a result of a new feature that Facebook was developing to give users a different way of sharing certain content.