Finnish security researchers Tomi Tuominen and Timo Hirvonen can clone many master hotel keys very quickly using their clever cryptography, an expired keycard from the hotel trash, and a $300 Proxmark RFID card reading and writing device. It takes them about one minute to create a master hotel key.
Security researchers demonstrate inexpensive one-minute method to clone master hotel key cards
Cryptography News
Security researchers demonstrate inexpensive one-minute method to clone master hotel key cards