The inconspicuous lock hacking device is an adaption of one demonstrated at the Black Hat security conference in July by Cody Brocious, a hacker and software developer for Mozilla, who discovered and exploited a vulnerability in Onity locks, a cheap and popular hotel room lock that the company says are used on at least four million hotel rooms worldwide.

FORBES: Hackers Crack Hotel Room Locks With A Tool Disguised As A Dry Erase Marker

Next year, Professor John Oxford, an expert in virology from Queen Mary's School of Medicine and Dentistry, in London, will lock volunteers in a hotel for a week, deliberately infect some with the flu virus, and wait to see what happens.

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Rather than pay for the full fix itself, which requires a new circuit board for every affected lock, Onity has asked its hotel customers to cover the cost of those hardware replacements.

FORBES: Security Flaw In Common Keycard Locks Exploited In String Of Hotel Room Break-Ins