June 7 (UPI) -- A software bug caused some Facebook users' posts to be shared with more people than they intended for a 10-day period in May, the company announced Thursday.
Facebook allows users to select who can view each of their individual posts, but the social network said Thursday that the bug changed the privacy settings of 14 million users to public -- allowing them to be viewed by anyone -- from May 18 to May 27.
The company said the error occurred as it was testing a new feature to allow users to highlight posts on their profiles, which inadvertently made all posts by the users default to a public setting.
The posts were marked as public, but users may not have noticed the settings had been changed.
Facebook said it reset all the posts to their original settings and began notifying affected users Thursday.
"Starting today we are letting everyone affected know and asking them to review any posts they made during that time," Chief Privacy Officer Erin Egan said. "We'd like to apologize for this mistake."
The bug comes as Facebook faces scrutiny over user privacy after information of up to 87 million people was improperly shared with data firm Cambridge Analytica.
CEO Mark Zuckerberg testified before a House committee about the breach in April and the company changed certain features to more closely protect users' personal information.
Cambridge Analytica, which worked on President Donald Trump's 2016 campaign, submitted a bankruptcy petition in U.S. Bankruptcy Court in the Southern District of New York on May 18, following the scandal.