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Hackers Can Track Subway Riders' Movements By Smartphone Accelerometer
Patrick O'Neill writes: Tens of millions of daily subway riders around the world can be tracked through their smartphones by a new attack, according to research from China's Nanjing University. The new attack even works underground and doesn't utilize GPS or cell networks. Instead, the attacker steals data from a phone's accelerometer. Because each subway in the world has a unique movement fingerprint, the phone's motion sensor can give away a person's daily movements with up to 92% accuracy.
Now if there were any subways anywhere near where I lived.
If the accelerometer has such poor security, what other components/sensors are vulnerable?
If you can get malware on the phone to read the accelerator then the game is over anyway. At that point you can steal text messages, email, passwords, etc. Who cares if they went from subway station A to B? They can get that info when they pop up above ground.
Everyone just needs to pool their phones and then everyone use a random phone for the day. Sort of a TOR operating at the physical level. An app that made encrypted VoIP calls could probably allow you to even use the same phone number by just logging in through the random phone of the day.
Doctors destroy health, lawyers destroy justice, universities destroy knowledge, religion destroys spirituality
If a hacker has access to accelerometer data, he/she probably has access to lots of OTHER personal info also.
Table-ized A.I.
The very premise, prior to the attack, is that the user has opted to run the "hacker"'s malware.
All they're saying, is that if run malware which watches the accelerometer, the malware can infer your location. And then it still has to transmit this information from your computer to another (unless the malware itself, is what make decisions based on your position).
Tin foil hat, now tin foil pocket.
The privacy concerns are troubling, but I can't help thinking that's pretty cool.
I find myself in the position asking, what's the news!? .. Where is the hacking?
And Hacker ??!?!
Ohh they needed a bad guy with a bad reputation.
Also hackers most likely beat you up the moment you engage in demonstrations (walking arround in circles = constant acceleration) and spray tear gas at you from 100m away because they have a GPS-enabled sniper rifle?
Ohh my fault that would be the chinese police and not a hacker.
"Summing" up the story:
Chinese Computer Scientists just found a copy of Newtons physics book. And were supprised to find that when you integrate accelerometer readings you first get the velocity and after another integration step you get the distance traveled in 3 dimensions +3 angles?
"accel (dt) -> velocity(dt) -> distance"
Some GPS-Navs have also accelerometers, to cover the dead zones for example when you are driving through a tunnel.
Also that unique movement character .. ohh please that's not research that's obvious, it goes for streets & walk ways too.
And the second best way to track peoples movement would be their cell data information, every cell tower can be uniquely identified, and a cell phone connects to three .. and when you keep track of these ..
The first best way is to access the gps data.
You and your government know where you were - also the "hacker" with the intent to kill, rape, rob or stalk you.
These malicous hackers must be known to be do-badders that try to know where you are, aren't hey?
Because 0% accuracy is also "Up To 92%" accuracy.
The title made me laugh. For once, this troll is on topic.
because only hackers could possibly do that, or have the interest to do it. Not other people. ESPECIALLY NOT the law-abiding people in law enforcement. They would never do that even if they could, which they can't, because they're not HACKERS.
because only HACKERS can HACK like HACKERS being HACKERS do, that's why.
Please, stuff it with the breathless bullshit. The truth is bad enough without meaningless embellishments for doubleplus extra scare value.
Here in Melbourne, Australia our train system has a unique movement footprint.
Accellerating and breaking for no reason, trains that skip stations or terminate at random ones; this baby's got it all. Good luck decoding the position from that.
iOS and presumably other platforms use the accellerometer & gyroscopes for purposes like this and to provide inertial navigation. Its quite accurate at locating you in a subway. I catch the train home a few times a week and its really quite remarkable.
To do signature matching of accelleration/decelleration patterns at specific stations would require low level access to the accelerometer data, or to bypass user consent on location services (on iOS)
I'm not sure on Android, but on WinMo and iOS you'd need to be jailbroken for this attack to work. (there is no low level API available unless you are in a rooted/jailbroken state).
Its a cool hack, but the preconditions for it being used as a surveillance mechanism are very significant compromises.
"Another interesting example is that if the attacker finds Alice and Bob often visit the same stations at similar non-working times, he may infer that Bob is dating Alice."
Man, that is scary! Good thing megacorps can't do that sort of...oh wait.
This isn't the first exploit which uses the accelerometers: Both reading taps on the display to snoop passwords and reading the vibrations of key presses on a nearby keyboard to reconstruct typed sentences have already been demonstrated. Yet access to the full raw accelerometer data is still not guarded by a permission in Android. Not only should this data only be available to apps if the user explicitly allows it, there should also be less intrusive filtered access, where the app only receives events like "display down", "falling", "double tap", etc., so that most apps won't need full accelerometer access for benign functions. And of course there should be a way to "allow" access, but withhold actual data from the app. That should be added for most existing permissions actually, not just accelerometer access.
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Nah, you're missing the point. Starts and stops will have 'fingerprints', spacing between stops will show up, things like that. Kinda cool research.
That particular subway system sways left to right, forward and backward. And drivers - there are two types. There are the cowboys who when they KNOW they have a packed train will come to sudden stops. Then there are the good ones, mostly the female drivers who gradually slow the trains.
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With a little more hacking, they could use the flashing light on Android phones to transmit the data.
Analog hole, bitches!
Who cares about this? Simply tracking which WiFi station IDs the phone sees is a lot better way of tracking where the person is.
If you can hack into their phone, you can find them. No need for fancy long-term acceleration tracking either.
http://lkml.org/lkml/2005/8/20/95
In the late 1970s in junior high we would ride the bus and get off at random stops and write down pay phone numbers. Then when we got home we would call the numbers and do all sorts of gags.
The one that inexplicably worked well was telling people that had won money from a radio station. Why they believed that an 8th grader sounded like a disk jockey is still beyond me.
It's almost kind of sad that kids of today can't get that experience. There's very few pay phones left and I bet none of them accept incoming calls. It was also pretty safe from a get in trouble perspective. Call logging and tracing would have been a huge endeavor and we never called any one pay phone more than a few times or suggested anything violent or even all that ribald.
The method should work, but I somehow doubt that "hackers" will be the ones bothering to use it. Much more likely to be used by police and intelligence agencies IMHO.
Mind you I would have thought that on a train you could triangulate with mobile repeaters and such much more easily,
Plus heuristics like the fingerprint of a train coming to a stop (and being stationary - no jagged movements and train like swaying). Train is stopped and person walking? Probably just got to a station nearest where dead reckoning says you should be.
As soon as I saw the summary, I wondered how they're able to do decent dead reckoning using the mediocre quality cell phone accelerometers; in the general case, the integration would give drift pretty quickly. We're not dealing with ICBM-quality accelerometers here. So the interesting bit is how they're able to make use of information that specializes the problem (the location of subway stations) together with machine learning to do much better than the general case. The paper is worth a read.
"Politicians and diapers must be changed often, and for the same reason."
Sorry, but who comes up with this shit? Apart from not knowing the start location and orientation of the phone, electric trains are all pretty similar these days and besides which how will they take account of non station stops at reds, bad riding suspension on certain trains, fast/slow drivers etc etc?
What a crock of ....
Apart from that the accelerometers on your average consumer device arn't even that accurate. After a few minutes it'll be hopelessly lost.
For a municipal transportation chief?