Could this key be used for hotels?

Hackers explain how easy it is to crack hotel doors - and how you can protect yourself

If you only want to break into a single room, you can build a burglary tool from a thick wire or a coat hanger for 50 cents. You just have to slide it under the door and pull the doorknob down.

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You can also bribe the room service staff or wait outside the room for the room to be cleaned and the door open. There are all sorts of tricks for opening a single door.

But if you are an important business person or the secret services are interested in you, things are different. If you are a target, you are at high risk.

As a normal guest, what can I do to be safe in the hotel?

Tomi Tuominen: You can easily defend yourself against an attack with the clothes hanger with a towel. If you put that around the doorknob, you can thwart that.

Timo Hirvonen: If the hotel door has an extra chain, you can at least lock it before you go to sleep. And if you have something of value with you, it's best to take it with you and not leave it in the hotel.

Is a hotel safe safe?

Tomi Tuominen: Never put anything in the safe! They are laughable. Look for "Safe" and "Potato" on YouTube. You can find instructions on how to open a hotel safe with a potato.

There is another more important reason never to put anything in the safe: That would save the attacker time. If I were the burglar and knew that the majority of people put their valuables in the safe, then I would scurry into the room and open the safe with a potato - done!

So if you have something of value with you and you absolutely have to leave it in the hotel, then hide it well. The average burglar will definitely not want to spend a long time in the room. Make it as difficult as possible to find your valuables or an important USB stick.

What would a really secure locking system for hotels be: old-fashioned keys, RFID cards or facial recognition?

Tomi Tuominen: It doesn't really matter whether we use doors with mechanical keys, electronic access tokens or biometric features. Every lock is only as good as the mechanics on which it is built. You have to involve IT security engineers in the development from the start.

Most of the companies that offer locking systems have their experience working with mechanical locks. But many such companies have little experience with software. They are trying to transfer their knowledge of physical security to the digital world. We saw how wrong this can go when we helped Assa Abloy to close her security holes. These are actually really smart people, but they have absolutely no idea what hackers think.

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