Several add-ons for WordPress are at risk of being hacked and redirecting users to harmful websites. This is because they rely on a tool called Polyfill.io. Polyfill.io is a type of code that helps websites run smoothly on older web browsers. Unfortunately, some bad people have taken control of Polyfill.io and are using it to send people to dangerous sites. Although not all WordPress add-ons that use Polyfill.io are dangerous, it’s best to update to a newer version of the add-on that doesn’t use Polyfill or to remove Polyfill.io from the add-on yourself.