A Facebook bug changed the privacy setting to public for 14 million users who thought they were making private posts - The Washington Post

Facebook apologizes for another privacy mishap....
https://www.washingtonpost.com/news/the-switch/wp/2018/06/07/a-facebook-bug-publicly-shared-the-posts-of-14-million-users-who-thought-they-were-making-private-posts/