Facebook hit by software bug which marked coronavirus posts as spam

Facebook has confirmed a bug in its spam filter removed posts incorrectly from the social network, including legitimate news articles about coronavirus.

Multiple users reported receiving alerts from Facebook saying their posts – often news stories from trusted sources about the spread of Covid-19 – had been marked as spam by the site and taken down.

Facebook’s Guy Rosen then confirmed on Twitter that the problem was “a bug in an anti-spam system”.

He denied suggestions the fault had been caused by Facebook relying more on artificial intelligence and automation for content moderation after it sent staff home as part of social distancing efforts to stop the spread of the virus.

Shortly afterwards, Rosen – the social network’s vice president of integrity – said the problem had been resolved.

“We’ve restored all the posts that were incorrectly removed, which included posts on all topics – not just those related to Covid-19,” he said.

“This was an issue with an automated system that removes links to abusive websites, but incorrectly removed a lot of other posts too.”

The incident comes after Facebook joined with other tech giants, including Google, Microsoft and forums such as Reddit to commit to working together to fight the virus.

The firms said they would help people stay connected during social distancing as well as work together to fight disinformation, fraud and conspiracy theories linked to the outbreak.

Social media, the government and the NHS have all warned about the spread of disinformation online, with platforms banning adverts and posts which promise cures to the virus, spread panic or make false claims about cases.

The NHS has previously highlighted a fake Twitter account which had posed as a hospital and posted misleading messages about cases of coronavirus before it was removed by Twitter.

Facebook, Google and Twitter all now show official NHS and government guidance on Covid-19 at the top of search results about the outbreak to help what the government called “good advice” to reach people.

Neighbourhood connection app Nextdoor has also updated its flagging tool so that any posts which are flagged as misleading and are linked to Covid-19 are reviewed immediately by its content moderation team.

In response to the ongoing threat of misleading content appearing online, the government has launched a specialist unit which is working with social media companies to monitor and remove coronavirus disinformation.