Facebook is now in the process of alerting millions of its users of a bug that occurred last month that might have made posts meant for a limited audience appear publicly.
Facebook remembers what setting you last chose and automatically selects it the next time you make a post.
A Facebook post's privacy settings, with a checkmark next to the users' chosen default setting. "We apologize for this mistake", the note reads, according to screenshots from TechCrunch.
The alert is being sent via Facebook's drop-down notifications menu, asking users to review the audience of their recent status updates in order to restore their previous privacy settings.
It is still unclear how numerous 14 million profiles that were affected may have posted content privately without realizing they were sharing publicly. The affected users will then be shown which posts were marked public during the glitch.
Facebook told BleepingComputer that the "error occurred while we were building a new way to share featured items on your profile, like a photo".More news: Real Madrid's Isco hopes Cristiano Ronaldo stays amid reports of contract dispute
Spotted by Recode, posts from up to 14 million Facebook users that had their content set to be shared privately was changed to be publicly seen.
The mixup was the result of a bug that automatically suggested posts be set to public, meaning the posts could be viewed by anyone, including people not logged on to Facebook.
Facebook has stated that these types of notifications will be used going forward to report privacy issues or breaches. In the process of creating this feature, Facebook said it accidentally made the suggested audience for all new posts public.
The news prompted swift response from lawmakers who asked Facebook for more information on those partnerships, and raised further questions about whether Facebook has violated a privacy agreement it had made with the government in 2011.
The company said the issue has been fixed and have blamed it on a software bug.
Facebook confirmed earlier this week that China-based Huawei - which has been banned by the USA military and is a lightning rod for cyberespionage concerns - was among device makers authorized to see user data in agreements that had been in place for years.