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Facebook Notifies 800,000 Users of Blocking Bug

Facebook on Monday started notifying 800,000 users affected by a bug that resulted in blocked individuals getting temporarily unblocked. The social media giant also detailed some new API restrictions designed to better protect user information.

When you block someone on Facebook, you prevent them from seeing your posts, starting conversations on Messenger, or adding you as a friend. However, a Facebook and Messenger bug introduced in May 29 and addressed on June 5 led to users being able to see some of the content posted by individuals who had blocked them.

According to Facebook Chief Privacy Officer Erin Egan, blocked users could not see content shared only with friends, but they may have been shown content shared with “friends of friends.” The blockee may have also been able to contact the blocker via Messenger.

Egan clarified that friend connections were not reinstated as a result of the bug and 83 percent of impacted users had only one blocked person temporarily unblocked. Affected users will see a notification in their account.

New API restrictions and changes

Facebook also announced on Monday additional measures taken following the Cambridge Analytica incident, in which personal data on tens of millions of users was improperly shared with the British political consultancy through an app.

The social media giant previously shared some information on the steps taken to better protect elections and user data, and it has now announced new changes affecting application developers.

Developers have been informed that several APIs have been or will be deprecated, including the Graph API Explorer App, Profile Expression Kit, Trending API, the Signal tool, Trending Topics, Hashtag Voting, Topic Search, Topic Insights, Topic Feed, and Public Figure. The Trending and Topic APIs are part of the Media Solutions toolkit.

Some APIs will be deprecated – including due to low usage – while others will be restricted.

Developers will once again be allowed to search for Facebook pages via the Pages API, but they will need Page Public Content Access permissions, which can only be obtained via the app review process.

As for marketing tools, Facebook announced that the Marketing API can only be used by reviewed apps, and that it’s introducing new app review permissions for the Live Video and Lead Ads Retrieval APIs.

Related: Facebook Suspends 200 Apps Over Data Misuse

Related: Facebook to Offer 'Bounty' for Reporting Data Abuse

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Eduard Kovacs (@EduardKovacs) is a contributing editor at SecurityWeek. He worked as a high school IT teacher for two years before starting a career in journalism as Softpedia’s security news reporter. Eduard holds a bachelor’s degree in industrial informatics and a master’s degree in computer techniques applied in electrical engineering.