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Battery power alone can be used to track Android phones

bbc.co.uk

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Re: Battery power alone can be used to track Android phones

#31

Post by wongarsu »

PJDK wrote: post #22
Jolijn wrote: post #21

Earlier quoted context omitted.

Technology is not exactly known to be stagnant. What is not practical now could be in just a few years. For high value targets, all bets are off anyway. Some nation states have virtually unlimited resources they can call on.

Yeah, exactly. This is just a back door to phone tower triangulation, something every nation state has access to and uses regularly and publicly as part of normal criminal investigations.

But phone tower triangulation is only readily available to nation states on their own soil. For tracking foreigners tracking signal strength might be a useful alternative.

Re: Battery power alone can be used to track Android phones

#32

Post by S_A_P »

wongarsu wrote: post #28
S_A_P wrote: post #26

Earlier quoted context omitted.

I get that part and to some degree understand. Maybe I am misinterpreting the "track your location" as something more accurate than "this person is in a 10 mile radius of this tower". For instance, wouldn't you need to know details of how different buildings are constructed? If you are in a busy downtown area, tracking with this method seems impossible. I could see if it was a remote area with few buildings to sift t…

Yes, it's not as trivial as just grabbing the data and running a generic algorithm. Ideally you would want to measure all routes where you want to track people. Kind of like how google knows where every wifi access point is and uses that for location information. Also, you need people to move. Because you only have power data, you only know the aproximate signal strength if the person isn't moving.

That makes more sense. So to me, the headline reads as "Location can be tracked just by measuring battery usage" when in reality its "Location can be tracked if: A) they know the tower you are speaking to B) they have information on how buildings are constructed in this area C) You move around D) they have some other crowdsourced info about how much power is required to talk to the tower you are connected to."

I can see this "technique" being used in an episode of NCIS, CSI or similar cop show. We need to find this guy, but all we have is his cell number.

Police tech #1 "Sure no problem, I will just connect to his phone and measure the battery drain..... Got him, he is Downtown at 5th and Main- lets go arrest him!!!"

Re: Battery power alone can be used to track Android phones

#33

Post by onion2k »

leereeves wrote: post #10
SifJar wrote: post #2

The article mentions that the required permissions are "very common permissions", and then in the next paragraph says that 179 apps on the Google Play store require those permissions. As of July 2014, there were 1.3 million apps in the app store [1]. That's ~0.014% of the apps on the store. Not exactly "very common" in my mind. Although the remark that they are "unlikely to raise suspicion" is valid, especially for t…

The typical consumer would probably just give the app access to the GPS. The hard part is getting them to download it. Interesting research but not the most practical attack.

Presumably this is an attack that would be targeted at an atypical user - someone security conscious enough to not give GPS permission to apps they install, and who would have switched off location services that would use wifi instead. In those circumstances you might assume that any tracking would be beyond the capabilities of anyone who didn't have direct access to the phone network. This proof of concept demonstrates that would be an incorrect assumption.

Re: Battery power alone can be used to track Android phones

#34

Post by 33W »

S_A_P wrote: post #23

Maybe I am a bit dense here, but how does battery drain map to a location? What would they be cross referencing to gather location? All I can gather is that they would also need to know what tower you were talking to, and then based on the drain they could probably guess where you were based on some heuristic. Meaning, if you are talking to tower x, and the battery drain is high, you could guess that you are either f…

I don't know the specifics, but if I were to implement this I would start by constructing a signal map of an area, then comparing the signature of changes to potential routes.

By having a sufficiently accurate map, you could determine the likelihood of a route by the changes in signal. Even without pre-mapping there are some estimations that could be made: a signal that follows a clean sinusoidal curve with a certain rate of change could likely be modeled by rural highway driving.

Re: Battery power alone can be used to track Android phones

#35

Post by [deleted] »

S_A_P wrote: post #32
wongarsu wrote: post #28

Earlier quoted context omitted.

Yes, it's not as trivial as just grabbing the data and running a generic algorithm. Ideally you would want to measure all routes where you want to track people. Kind of like how google knows where every wifi access point is and uses that for location information. Also, you need people to move. Because you only have power data, you only know the aproximate signal strength if the person isn't moving.

That makes more sense. So to me, the headline reads as "Location can be tracked just by measuring battery usage" when in reality its "Location can be tracked if: A) they know the tower you are speaking to B) they have information on how buildings are constructed in this area C) You move around D) they have some other crowdsourced info about how much power is required to talk to the tower you are connected to." I can…

[deleted]

Re: Battery power alone can be used to track Android phones

#36

Post by [deleted] »

S_A_P wrote: post #32
wongarsu wrote: post #28

Earlier quoted context omitted.

Yes, it's not as trivial as just grabbing the data and running a generic algorithm. Ideally you would want to measure all routes where you want to track people. Kind of like how google knows where every wifi access point is and uses that for location information. Also, you need people to move. Because you only have power data, you only know the aproximate signal strength if the person isn't moving.

That makes more sense. So to me, the headline reads as "Location can be tracked just by measuring battery usage" when in reality its "Location can be tracked if: A) they know the tower you are speaking to B) they have information on how buildings are constructed in this area C) You move around D) they have some other crowdsourced info about how much power is required to talk to the tower you are connected to." I can…

[deleted]

Re: Battery power alone can be used to track Android phones

#37

Post by quickyaccnt »

S_A_P wrote: post #32
wongarsu wrote: post #28

Earlier quoted context omitted.

Yes, it's not as trivial as just grabbing the data and running a generic algorithm. Ideally you would want to measure all routes where you want to track people. Kind of like how google knows where every wifi access point is and uses that for location information. Also, you need people to move. Because you only have power data, you only know the aproximate signal strength if the person isn't moving.

That makes more sense. So to me, the headline reads as "Location can be tracked just by measuring battery usage" when in reality its "Location can be tracked if: A) they know the tower you are speaking to B) they have information on how buildings are constructed in this area C) You move around D) they have some other crowdsourced info about how much power is required to talk to the tower you are connected to." I can…

The article links the article where the authors suggest they don't need to know which tower you're connected to (in which case you could get a more accurate location from the towers themselves).They assume the only information you have from the phone is the power usage. However, they also assume the attackers have a general idea of your habits, and can therefore map out cell reception in the city where you live.

The "general habits" assumption seems implausible, but it isn't. Let's say you want to track all the citizens of the Bay Area. You know that, in general, ppl from the Bay area are in the Bay Area. Therefore, you map the cell reception in Bay area. You also take note of major transportation routes and patterns. Now, if you want to track a particular target, all you'll need is their power usage.

Re: Battery power alone can be used to track Android phones

#39

Post by lm2s »

What a sensasionalist headline... The results of the study can only be achieved under a very controlled environment and even then they're not accurate. From a practical point of view this is irrelevant when there are other ways of getting a user location that are far more accurate and easy. But from an academic point of view I can see the interest.

Re: Battery power alone can be used to track Android phones

#40

Post by tedunangst »

PJDK wrote: post #8

This is really selling a quite interesting intellectual effort on meaningless paranoia. Who would have any interest in tracking people in this manner? Any government based group can grab the data much more conveniently via the phone towers. Anyone else? Well you've got to trick someone into downloading this thing, so it's probably not that good for targeting a specific individual. If you can think up some nefarious s…

Confirmation or double checking that the user isn't spoofing GPS?

Though it seems the results would be useless if a Stringray were in the vicinity, and I thought the assumption was that Stingrays were everywhere.

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