I OPENED THE REAR GLASS AND WHILE THE GLASS WAS BEING RAISED BY THE PISTONS, I HEARD A LOUD BANG. THE GLASS SUDDENLY SHATTERED ALL OVER ME AND THE BACK OF THE MOUNTAINEER. I GOT GLASS IN MY FACE AND ARMS AND FEET. I HAD LACERATIONS TO MY ARMS FROM THE GLASS AND GLASS SPLINTERS IN MY FEET WHERE THE GLASS GOT INTO MY SHOES. THE GLASS DID NOT HIT ANYTHING AS WAS ONLY PART OF THE WAY UP WHEN IT SHATTERED. I DID NOT OPEN THE FULL REAR GATE, JUST THE GLASS PANEL WHICH IS UNLOCKED WITH A PUSH BUTTON TO THE RIGHT OF THE REAR GATE HANDLE LATCH. THE DAY WAS HOT AND I HAD THE AC RUNNING SO THERE WAS TEMPERATURE GRADIENT INSIDE OF THE VEHICLE TO THE OUTSIDE. THIS IS A DANGEROUS DEFECT AS I WAS INJURED AND OTHER COULD BE MORE SEVERELY INJURED BY THIS DEFECT.