You might have missed the news about a FaceTime bug that was found about a year ago. The bug enabled anyone to start a group FaceTime call with one of your contacts, even if that person didn’t explicitly accept the call. Apple disabled group FaceTime calls for a couple of days until it was able to issue a patch in iOS 12.1.4. Since then, Google security researchers have been busy finding the same bug in other group chat apps including Signal, JioChat, Mocha, Google Duo, and Facebook Messenger.
In my blog for Avast, I go into details about this bug, how a teenaged gamer discovered it, and how it was tamed.