Facebook bug unblocks people on 800K+ accounts

Do you block anyone on Facebook? They might have recently gotten a peek at your Facebook activity anyway thanks to a bug.

The social network is notifying more than 800,000 users "about a bug in Facebook and Messenger that unblocked some people they had blocked" between May 29 and June 5, Erin Egan, Chief Privacy Officer, wrote in a blog post.

The problem didn't give blocked individuals full access to a person's account, but "they could have seen things posted to a wider audience. For example pictures shared with friends of friends."

Facebook apologized for the bug and said it has been fixed. People are once again blocked, but Facebook will add an alert to the accounts of those affected, asking them to double-check their blocked lists.

If you block someone on Facebook, they can no longer see things you post, start a chat on Messenger, or add you as a friend. According to Facebook, about 83 percent of the people affected by this bug had only one person temporarily unblocked, but it would have allowed them to make contact via Messenger.

Egan acknowledged that the issue is a serious one; when you block, you "may want to take a break from someone [but] other reasons are more serious like harassment or bullying," she wrote.

This comes a month after Facebook disclosed a software bug, which, for several days in May, changed the suggested audience of all new posts to "public."

Facebook's audience selector tool usually remembers the audience you shared with the last time you posted something (public, friends, friends except..., or only me) and suggests the same audience when you share again. But between May 18 and May 27, some 14 million people made public posts on the social network, many of them likely believing they were sharing with just friends.

This article originally appeared on PCMag.com.