A hacker took credit for making a master key to unlock any hotel room with Onity programmable key card lock.
Cody Brocious a security researcher said that he has made a master key to access almost all the doors with Onity lock by using a home-made gadget.
The details about the claims will be revealed at the Black Hat conference in Las Vegas this week.
While Onity said it would look into the matter of mimicking the key by Brocious's and will work and address "any potential issues."
Onity claims to have installed more than 10 million locks in a number of hotel chains around the world.
"We will review and analyze Brocious's presentation and any other information that he publishes on this subject," the company told the BBC in a statement. "Onity places the highest priority on the safety and security provided by its products and works everyday to develop and supply the latest security technologies to the marketplace and is prepared to address any potential issues posed by the presentation."
Brocious described how he managed to make the master key as he used a cable connected to a DC power port below the door lock, and plugged it into a portable programming device he had built for $50.
He told that the device is based on the Arduino operating system and mimics ones it is used by the hotel staff to control which master keys open which doors.
Brocious said he discovered that every lock's memory was exposed to whatever device attempts to read it through the DC power port and he accomplished this by the method of by reverse engineering.
Brocious conducted the tests with Forbes news site. However the system did not prove entirely successful as only one of the three doors, at three hotels in New York, opened. Brocious plans to release all his research and source code on his website.
He is currently working as the chief technology officer for a startup called Unified Platform Management Corporation. This company competes with bigger players in the hotel lock industry.