Facebook is trying to stop an attack that has infected a large number of ads on its site and its advertising platform, including some that have been used by governments and others that have targeted foreign governments.
The social media giant said it has identified some ads that may have been affected by the attack and is working with the advertisers to fix the issue.
Facebook said the issue could have affected as many as 20 million users who visited Facebook in the past 24 hours.
“We are working to help advertisers and governments with their ads, so they don’t get infected,” said a spokesperson for the social media company.
“As a precautionary measure, we have disabled some ads on the Facebook platform, and we will continue to work to make sure those ads don’t appear.”
Facebook said it identified the issue through its “Ads by Country” feature, which lets users search for adverts that are relevant to their country.
It said it had “zero tolerance” for such adverts and that ads were not affected.
It added that the issue was likely to affect other Facebook platforms, including its own Messenger app, as well as the advertising service Ads By Country, which offers search capabilities to advertisers.