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GPS Spoofing With $3000 Worth of Equipment and a Laptop 180

First time accepted submitter svartbjorn writes "Todd Humphreys and a team from the University of Texas proved the concept that a terrorist could take over the navigation of a ship or even a plane, making it appear to the crew that the ship was moving along a straight line course when in fact it was changing course under the control of the device. This raises some serious issues for this being used for terrorist purposes."
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GPS Spoofing With $3000 Worth of Equipment and a Laptop

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  • by Anonymous Coward on Friday July 26, 2013 @08:32PM (#44396215)

    Old news. If you want a less sensationalistic, more technical discussion of how this is done, see this article

    In brief:
    1) Yes, it's possible but there are a lot of issues that make it less than practical
    2) It's a non-issue for military positioning systems, which use encrypted, time-stamped signals.
    3) Experts are already aware of the problem and are working on solutions.

  • by ebno-10db ( 1459097 ) on Friday July 26, 2013 @09:52PM (#44396665)

    Try reading the paragraph that starts with "Developing a full spoofer-based control system for a UAV is a difficult problem..."

    You mean the paragraph that also says "causing a UAV to spin out of control and crash is not difficult with a spoofer"?

    "Constructing from scratch a sophisticated GPS spoofer like the one developed by UT is not easy..."

    Which ends with "the trend toward software-defined GNSS receivers for research and development, where receiver functionality is defined entirely in software downstream of the A/D converter, has significantly lowered the bar to spoofer development in recent years."

    or the one that starts with "There are also a number of promising non-cryptographic techniques for civil GPS spoofing detection...".

    Which certainly jibes well with my statement that "it is possible to fix".

    You're welcome to pay attention if you feel like it but it won't get the problem fixed any faster.

    That's true of most of the news I read. Should I take it that you never read news or consider the possibilities unless changing it is under your direct control? If so, why are you even reading this site or commenting here?

  • by EmperorArthur ( 1113223 ) on Saturday July 27, 2013 @01:14AM (#44397421)

    Ahh, but you can sign those packets the GPS satellites are sending. The US military uses encrypted GPS to prevent precisely this kind of attack. It also allows them to use their selective denial system to cut off part of the world without affecting their own systems. Ask the Russians about what their latest trip into Georgia taught them about their reliance on GPS.

    So, yes the US can fix it, and should. Every country that is working on their own GPS alternative should as well.

    Software defined radio is changing the world. It's bringing the price to capture signals down to a $20 USB TV tuner, and the price to send signals to a few thousand dollars. Not bad for something that used to require millions in fab costs to build transmitter ASICS.

  • by tibit ( 1762298 ) on Saturday July 27, 2013 @07:32AM (#44398379)

    What you claim as facts is a bunch of made up rubbish, sorry. First of all, what do you mean by tokenisation of communication? If you mean that tokens = packets than that's insane, so let's hope you mean something lese. Why the heck do you even need to talk about tokenisation?

    If you like a doofus imply that encryption makes things less reliable, then that's just borderline clinical insane. Protip for the clueless: it's precisely the encryption of GPS's P-code that makes it pretty much spoof-proof. These days there are P(Y)-code receivers that don't need the hand off word (HOW) from C/A code. To accomplish that feat, they use optical correlators that perform the Fourier transform needed for fast correlation of the very long P(Y) code with the incoming signal in order to detect where in the sequence the code is, without using HOW. There's no one spoofing that.

    While spoofing is somewhat theoretically possible, it'd require a fairly gargantuan effort. You'd need a station with a bunch (dozen) of fairly large (IIRC ~10m diameter) dishes tracking the individual satellites. And you'd need stations all around the globe so that you would have continuous coverage of all the satellites - the number of stations would be in the dozens, too. You could then receive good signal from each satellite individually, signal good enough to just read the P(Y) code without doing the correlations. As I've said, that's pretty crazy, and no single nation could pull it off since you really need to install equipment all over the world, and it's not stuff that fits in a suitcase. Oh, and of course you'd need to collect all those signals, put them through signal processing to recode them with fake data, and then transmit that in real time to the location where you intend to spoof stuff. I'm pretty damn sure the military receivers don't like date rollbacks, so it's not like you could record stuff last year and transmit this year.

    Alas, GPS signal's encryption utilizes a stream cipher and not public key cryptography. But they do use public key crypto for key management. If it's ever found out how to break the cipher to extract the key, they may simply re-key the receivers more often - presumably the key extraction won't be an overnight thing. Now of course PKC is not the hardest thing to implement, far from it [], as it can be done even on tiny 8 bit microcontrollers. But even RSA is still state of the art public key crypto, so you can get pretty good results without making it complicated. No need for complications, really.

    So, you're just full of it. Where on Earth did you learn all this crap, or are you on some purposeful disinformation campaign?

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