Facebook said a software bug led some users to post publicly by default regardless of their previous settings. The bug affected as many as 14 million users over several days in May.

The problem, which Facebook said it has fixed, is the latest privacy scandal for the world’s largest social media company.

It said the bug automatically suggested that users make new posts public, even if they had previously restricted posts to “friends only” or another private setting. If users did not notice the new default suggestion, they unwittingly sent their post to a broader audience than they had intended.