There has been known weaknesses with the various key less entry solutions among cat manufacturers, the debacle on the system used by JEEP springs to mind. Now we see a weakness in the Mercedes Benz solution. In a video released by the West Midlands Police in the UK we see thieves sniffing out the key code from the key inside of the house, and then transfers it to a sender by the car to open and start the car. Time to look at at NFC blocking key storage I suppose.