The popular Cardkey system (especially popular for hotel doors and gates) has been helplessly exploited by security researcher Ian Robertson. He has managed to build an Android app that he can use and unlock the doors for a generous time period of 30 seconds.

Check out his demonstration here:

Seeing as how most Cardkey systems are IP-based, his app is able to easily crack the code and send it over his phone’s Internet into the device to issue it an unlock command. Pretty cool, though this really shows how bad the security is if takes just a click of a button to open the doors.

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