A newly discovered iOS bug lets the caller listen in before you accept the call, 9to5Mac reports. If the recipient tries to silence or dismiss the call by pressing the volume down button or the power button, the camera activates without their knowledge. Thus, the caller might end up unwittingly eavesdropping on the person they have been trying to reach.
Apple has been notified of the problem. Until the matter is fixed, it has disabled the Group FaceTime function, and the update aiming to fix the bug should be out later this week.