Thursday, April 23, 2015

Keyless auto entry systems: keep your key fob in the freezer

Seriously:
Last week, I started keeping my car keys in the freezer, and I may be at the forefront of a new digital safety trend.
Let me explain: In recent months, there has been a slew of mysterious car break-ins in my Los Feliz neighborhood in Los Angeles. What’s odd is that there have been no signs of forced entry. There are no pools of broken glass on the pavement and no scratches on the doors from jimmied locks. But these break-ins seem to happen only to cars that use remote keyless systems, which replace traditional keys with wireless fobs. It happened to our neighbor Heidi, who lives up the hill and has a Mazda 3. It happened to Simon, who lives across the street from me and has a Toyota Prius.
Pretty good article in the NYT on something that I've been writing about for a while.  The $30 device that lets people break in to your car is easily available, and keeping your key fob in your kitchen freezer will defeat the attack.  No, this isn't a joke, although the security of the keyless entry system sure seems to be.

Hat tip: Dave, via email who adds: "This one is Face Palm worthy".  Sure is.


10 comments:

Captain Wheelgun said...

Is there some specicic reason to use the freezer, or would any metal box do? If I understand correctly, the freezer is just acting as a Faraday cage, blocking RF signals.

Dave H said...

Any metal box will do, although one that's grounded electrically will work a little better. The freezer or refrigerator will work equally well.

I don't recommend the oven or microwave though. That could be painful.

Borepatch said...

Agree with Dave H. I would think that as a Faraday Cage, a freezer would leak RFI pretty badly (via rubber door seals, etc).

I also expect that some of the benefit comes from the cold reducing the battery voltage, which I would expect would attenuate the signal pretty drastically.

Dave H said...

BP, the wavelength of the frequencies used by keyless entry systems are long enough that they still won't penetrate the 1/2" gap along the freezer door seal very well. This is a very low power device that was only intended to work at a distance of a few meters. It doesn't take much to interfere with it.

Also, the walk-up keyless entry remotes like this box exploits need to hear a signal from the car before they respond. If you can block that, the remote remains silent.

drjim said...

Or just wrap it up in aluminum foil.....

Comrade Misfit said...

Just get a small steel tool box. You could mount it someplace handy and always drop your keys into it.

Divemedic said...

Doesn't the range of the key play a larger factor than the range of the car?
I have heard so many breathless warnings on the internet that explain how some mysterious technology is useless and going to kill us all, that I take all of these with a LARGE grain of salt.

genericviews said...

What am I missing? Keyless entry systems have been around for 20 years. It is hard to find a car today that doesn't have one. Yet every car isn't getting broken into. Are there just not enough thieves to go around? maybe this is another job that Americans won't do and we need to import more third worlders. My own keyless entry system on the key fob only activates when I push a button, so I don't need to keep it in the freezer. Also, I put may whole car into a box called a "garage" at night. Further, I don't live around thieves.

But if you live in a neighborhood where thievery is common, wouldn't you rather that the thieves unlocked your doors than broke your windows? How you lock the car does not prevent the thief from his life of crime. It only forces him to select a different entry method that will be more costly to you.

I recall back before there were power door locks, there were still thieves who would break into cars. Car owners in those neighborhoods would practice not keeping valuables in their cars and even leaving them unlocked so that the thieves would not damage the cars to get into them.

Borepatch said...

genericviews, what's different is that with the new ones you don't have to push a button. I.e. with the old system the only way the attack would work is if you were pushing the button in your kitchen (or wherever) while the thief was by your car.

Now the car automatically unlocks when it gets the signal.

Technically, the signal is always on now, and used to only be on when you pushed the button.

Jason Donald said...

Probably not a good idea to stick your fob in the freezer. Might be easier to stick them in a "Fob Guard" from... wait for it... http://www.fobguard.com