If you haven't updated your iPhone yet to regain access to Group FaceTime, this is an even better reason to switch to iOS version 12.1.4 as soon as possible. The changelog mentions "important security updates", and those include a fix for the Group FaceTime bug that was recently publicized. It was able to disable group FaceTime on the server side and bundled a more permanent solution with operating system updates released just a few days later.
It's not clear how much Apple will be paying the family, but it was previously confirmed that the discovery was eligible for Apple's bug bounty program, which offers rewards of up to $200,000 for security researchers who find vulnerabilities on Apple's software platforms. "To protect customers who have not yet upgraded to the latest software, we have updated our servers to block the Live Photos feature of FaceTime for older versions of iOS and macOS", the company said in a media statement, as reported by 9to5Mac.
Apple plans to contribute to his college fund and will also pay a bounty to him and his family for reporting the bug. Later his mother, Michelle Thompson informed Apple about the bug and also asked them to fix it as well.
Over a week ago, it was discovered that 3rd party callers could potentially eavesdrop via FaceTime if they initiate a Group FaceTime without having you to accept the call.
Now, Apple has credited Grant, who's from Catalina, in Arizona, with finding the flaw. Available for download now, iOS 12.1.4's release notes claim the flaw is over, thanks to "improved state management". At least one other person has come forward to say they disclosed the flaw to Apple before it was publicized.
You can also install macOS Mojave updates by going to System Preferences and then clicking on the Software Update icon.
So if your phone seems sluggish after iOS 12.1.3 upgrade and if you wish to downgrade back to a lower version, it seems you simply can not as Apple has blocked it.