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Texas students fake GPS signals and take control of an $80 million yacht

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Re: Texas students fake GPS signals and take control of an $80 million yacht

#21

Post by hedgie13 »

mikeash wrote: post #17
hedgie13 wrote: post #8

Earlier quoted context omitted.

There is more airports in US that have GPS only approaches than airports that have ILS approaches. For example: http://155.178.201.160/d-tpp/1308/05879R25.PDF 500 ft altitude with GPS only (without vertical guidance). LPV minimum is 300 ft. Category III ILS minimum is 200 ft, Cat II -- 100 ft. But there are a lot of airports where ILS is not available.

A lot of small airports with very little traffic. Counting airports doesn't give you an accurate picture, because just about any airport can have a GPS approach, since the whole point is that it doesn't require any ground equipment. That doesn't mean those approaches get much use, because people don't fly into those airports all that much, especially not on instrument approaches. I fly out of an airport with a publis…

True, they are less busy, but it does not mean GPS is not used for instrument approaches (as parent implied).

I fly airplane without IFR GPS (IFR student), but ATC is trying to assign us GPS approach all the time (when coming into airport with ILS). As far as I understand, GPS approaches are used, even if they are less critical in busier airports. Besides, sometimes ILS is not available in bigger airports as well.

Re: Texas students fake GPS signals and take control of an $80 million yacht

#22

Post by michaelt »

tlrobinson wrote: post #19
unoti wrote: post #13

Earlier quoted context omitted.

The article is interesting. Take a look at it. "By putting noise [jamming] on the communications, you force the bird into autopilot... Notably, it's also much easier than trying to crack the encrypted remote-control communications channel. With the drone relying solely on GPS to determine its latitude, longitude, altitude, and velocity, the Iranians then broadcast carefully spoofed GPS coordinates..."

Parent comment says the military uses encrypted GPS , which should protect against this type of attack.

What do you suppose a drone does if the command channel and the encrypted GPS signal are both unavailable/jammed but the unencrypted GPS signal is available?

In any case, you don't have to be able to decrypt a GPS signal to be able to replay it - you fly a plane 200m above the drone, record whatever's coming over the air from the satellites and you know precisely what would be at the drone's antenna if it were 200m higher. Rebroadcast that at the drone's antenna et Voilà, the drone thinks it's 200m higher than it is.

Re: Texas students fake GPS signals and take control of an $80 million yacht

#23

Post by ksrm »

As mentioned in the paper, a simple solution if there is internet connectivity is to verify that the ephemeris is correct. This is how assisted GPS works in mobile phones and the like anyway (the ephemeris and almanac data are downloaded over the network to increase acquisition times).

Re: Texas students fake GPS signals and take control of an $80 million yacht

#24

Post by mbrameld »

zackbloom wrote: post #5
yread wrote: post #4

Yeah if they just used their paper charts, logged the position and compared GPS with the dead reckoning (or depth lines, radar shore returns,..) the attackers would have a much harder time... My sailing instructor always stressed that GPS is unreliable and especially when close to danger one should cross check what it says with other methods. Came in handy when my plotter failed.

There is more to it than that though. Aircraft often fly instrument approaches using GPS alone, getting to within 500 feet of the ground while still in clouds. If someone could make the aircraft think it was just a couple extra miles in the wrong direction it could be disastrous.

Do you have a source for aircraft flying using GPS alone? My understanding is that they rely on VOR and ILS systems.

Re: Texas students fake GPS signals and take control of an $80 million yacht

#25

Post by forgottenpaswrd »

So a $80 million yatch can't afford an $3000 high quality gyroscope?

Now you could buy amazing laser gyroscopes, for planes the Inertial navigation system error could be great, but for ships(that move more than 20X slower) is not.

Re: Texas students fake GPS signals and take control of an $80 million yacht

#26

Post by jevinskie »

michaelt wrote: post #22
tlrobinson wrote: post #19

Earlier quoted context omitted.

Parent comment says the military uses encrypted GPS , which should protect against this type of attack.

What do you suppose a drone does if the command channel and the encrypted GPS signal are both unavailable/jammed but the unencrypted GPS signal is available? In any case, you don't have to be able to decrypt a GPS signal to be able to replay it - you fly a plane 200m above the drone, record whatever's coming over the air from the satellites and you know precisely what would be at the drone's antenna if it were 200m h…

I would hope the engineers designing the drone would NOT fall back to the unencrypted channels precisely because of spoofing attacks. I would think they would rather have the drone use inertial guidance to get it to a friendly area where its secrets would be safer. It may not be able to land without GPS but it would have prevented it from falling into "enemy" hands. Perhaps even activate a self destruct mechanism(s).

Re: Texas students fake GPS signals and take control of an $80 million yacht

#27

Post by beat »

hawkharris wrote: post #20
jug6ernaut wrote: post #9

Click bait title(same as the article, for what its worth). $80mil yacht uses same GPS as a $80 sell phone, the 6 zeros dont change that. To the actual issue, i wonder how practical this is? In that i mean what level of power output is required to override the correct signal and at what distance? Is this something that could be a real issue, impractical? What?

"$80mil yacht uses same GPS as a $80 sell phone, the 6 zeros dont change that." When gauging the newsworthy-ness of a problem, the scope of its impact is always one of the first factors that journalists consider.

Or the appearance of scope. An $80M yacht sounds impressive, but widespread hacking of a million $80 phones would be far more potentially awful.

Re: Texas students fake GPS signals and take control of an $80 million yacht

#28

Post by eksith »

michaelt wrote: post #22
tlrobinson wrote: post #19

Earlier quoted context omitted.

Parent comment says the military uses encrypted GPS , which should protect against this type of attack.

What do you suppose a drone does if the command channel and the encrypted GPS signal are both unavailable/jammed but the unencrypted GPS signal is available? In any case, you don't have to be able to decrypt a GPS signal to be able to replay it - you fly a plane 200m above the drone, record whatever's coming over the air from the satellites and you know precisely what would be at the drone's antenna if it were 200m h…

That would only work if it had a really silly default similar in a way to "automatically connect to available Wi-Fi network" even when it's unsecured. It's possible the manufacturer may have overlooked something like that, but if it is in a military capacity, I doubt they would have left a gaping hole like that. Electronic countermeasures have been in use for several decades now so jamming/hijacking etc... would have been considerations in the design and they may have introduced hardening against those.

Re: Texas students fake GPS signals and take control of an $80 million yacht

#29

Post by jevinskie »

I discussed this with my friend yesterday and wondered about key management with the military GPS channels. Is there a single key that, if extracted* from just one military GPS receiver, could spoof all military signals? Or are there multiple keys, possibly with a revocation scheme? GPS is getting old, what was the state of the art key management back then?

* I'm sure the anti-tamper technology is pretty great.

Re: Texas students fake GPS signals and take control of an $80 million yacht

#30

Post by toomuchtodo »

hedgie13 wrote: post #21
mikeash wrote: post #17

Earlier quoted context omitted.

A lot of small airports with very little traffic. Counting airports doesn't give you an accurate picture, because just about any airport can have a GPS approach, since the whole point is that it doesn't require any ground equipment. That doesn't mean those approaches get much use, because people don't fly into those airports all that much, especially not on instrument approaches. I fly out of an airport with a publis…

True, they are less busy, but it does not mean GPS is not used for instrument approaches (as parent implied). I fly airplane without IFR GPS (IFR student), but ATC is trying to assign us GPS approach all the time (when coming into airport with ILS). As far as I understand, GPS approaches are used, even if they are less critical in busier airports. Besides, sometimes ILS is not available in bigger airports as well.

ILS was not available on the SFO runway the Asiana aircraft crashed on ~2 weeks back:

http://en.wikipedia.org/wiki/Asiana_Airlines_Flight_214

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