A major bug was recently detected in Apple’s FaceTime; through group calls you can now hear the person on the other side of the call before picking up or rejecting the call.
Apple claims to address fixing the bug in a software update coming out at the end of the week and till then they have taken group calls down to avoid any repetition of the issue.
The issue is more about privacy problems. You’re able to hear any iOS device user without them knowing, as the receiving iPhone keeps ringing normally.
The bug happens when the caller adds himself to a group call with the original call, this lets the other side of the call answer, thus, the caller hears the receiver but the receiver’s phone is still ringing.
— Benji Mobb™ (@BmManski) January 28, 2019
This does not stop here, it was found that if the caller presses their power button from the lock screen, the receiver’s video is transmitted back to the caller. At that point, the receiver does not know that besides their audio, their video is also sent to the caller.
There’s no way still known to defend yourself from this bug, and Apple advises its users to disable the FaceTime feature in settings until the issue is fixed in the next software update.