Thieves are now finding it easier than ever to break into hotel rooms which issue guests with magnetic cards to unlock doors.
According to The Sunday Times, thieves are increasingly gaining access to locked rooms simply by using a small device which can be plugged into a maintenance port at the base of the lock. This allows the thief to discover the combination to the lock and open the door.
Cody Brocious, an independent security researcher, claims that the device is easy to build at home - and costs as little as £20.
Jim Stickley, chief technology officer for the security firm TraceSecurity, told The Sunday Times: "Go online, follow his step-by-step instructions, and even a village idiot could build one in half an hour."
This poses a significant security risk as the card lock system is used on the doors of around four million hotel rooms worldwide - including Marriott, InterContinental and Hyatt hotels.
BBC News reports that the technique was first detailed by Cody Brocious in July and his technique has since been refined by others. A few rooms at the Houston Hyatt in Texas have already been burgled in this way and the hotel has now filled the holes with thick glue to prevent any more incidents.
The card lock system - or the HT system, to use it's proper name - is manufactured by Onity. It uses an electronic code, usually held on a magnetic key card, to unlock doors. So far, Onity has responded to the problem by providing a metal cap that covers the maintenance port but, following a wave of hotel-room robberies, it has now offered to start replacing the circuit boards in millions of vulnerable locks.
However, this will take time and many hotels are now advising guests to store valuables in the room safe and use a security chain when they are sleeping.
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