Or, Maybe the Military’s GPS System Has Been Hacked

Yesterday, we linked to this AP story that said the Air Force found a software glitch during its upgrade of the ground control stations for a new fleet of GPS satellites that rendered about 10,000 GPS receivers inoperable. The Air Force said it has begun distributing a permanent software fix.

The story quoted Air Force Space and Missile Systems Center spokesman Joe Davidson who said: “We are extremely confident in the safety and security of the GPS system from enemy attack… Since GPS’ inception, there has never been a breach of GPS.”

Yet, earlier this year, Colin Clark at companion site DOD Buzz, reported on public comments by Air Force chief Gen. Norton Schwartz, where he said “GPS signals are particularly vulnerable in time of war since enemies know of the reliance U.S. forces place on its highly accurate signal.” Schwartz said the military must find alternatives to GPS when operating in denied environments because of the system’s vulnerabilities.

“Schwartz’s call is driven by serious threats to GPS, according to officials familiar with the issue who would not discuss current threats in detail but confirmed that GPS has been jammed or interfered with recently,” Colin wrote.

(h/t: Robert Charette)

— Greg Grant

  • SMSgt Mac

    Or how about maybe not?
    Geez, the AP piece is referenced so I assume we should read it . Yet somehow all that is mentioned within and attributed to credible sources,
    such as the problem WAS related to new software to support the new, improved GPS capabilities coming with the constellation update and the glitch actually affected only a subset of Trimble receivers that represent a very small percentage of the military’s GPS systems- all of it – is to be discounted and perhaps doubted as somehow less than credible….just because a fertile imagination MIGHT be able to free-associate unverifiable, comments made in the past by the ever-present ‘unnamed officials’?

    The all-up AP piece has all you need to know with extra pundit sprinkles on top.

  • SMSgt Mac

    Full disclosure: In the mid-80s I co-authored a paper for symposium that received a love-hate response when presented because it contained a caution against over-reliance on GPS. I asserted that (like all signals) it could be jammed. At the time, it was commonly believed that it could not be jammed for a variety of reasons (such as the signal was buried in noise and was tough to even detect at the time) -all of which had fallen to the wayside before the decade was out.
    Jamming and cracking are two entirely different nuts.

    • TrustButVerify

      “Jamming and cracking are two entirely different nuts.”
      What he said!

  • Adam

    Not to mention, hasn’t it been readily available info that you could, fairly easily, jam GPS signals in a given area?

    “confirmed that GPS has been jammed or interfered with recently” could mean a lot of things, and sort of implies a “reciever-side” type of interference, given all of that, i’d say it’s a safe bet to guess it was more of the jamming type interference, than the hacked-the-sats type of infinitely more complex interference.

  • TMB

    Your Walmart Garmin is easily jammable without needing very expensive equipment (which is why they’re banned in the war zone). With getting into the how-to, you’re messing with the GPS unit’s ability to receive signals. Military GPS is encrypted just like our radios, so its not like you just break into the actual bird and mess with things.

  • If they can jam miGPS, what about civil GPS?
    Very scary indeed.
    Must secure systems or Lose.

    • Civilian and miltiary GPS run off the same satellite constellations.

  • Dean

    SMSGT Mac is on to something here. We are WAY to dependent upon GPS for everything-not only military, but also ocean navigation, commercial banking, network timing, telecommunications, and all of the stupid people out there who can’t get across town with their GPS devices talking to them. As in all war, the first thing you take out is the enemies ‘eyes’ i.e. there ability to know what’s going on. The GPS satellites will be prime targets in any real war. We should create a separate GPS system for military use only (like it was in the beginning). These satellites will be special with on board scanners to detect threats and manuevering rockets to avoid threats, etc. etc.

  • Locarno

    “These satellites will be special with on board scanners to detect threats and manuevering rockets to avoid threats, etc. etc.”


    A GPS-equivalent system is like a series of lighthouses you can draw bearings to. Which means it has to be (a) stationary relative to earth and (b) effectively continuously radiating or you can’t actually do anything useful with it.

    Which, in turn, makes it a fairly prime target for those with the capacity to hit something in g/s orbit.

  • Curt

    The sattelites are not in Geostationary orbit, they are at 1/2 Geostationary so there is global coverage but still almost impossible to attack. As pointed out, jamming a GPS receiver is not real difficult, you just need a signal on the same frequency that can degrade the signal. However, with a protected receiver, the jamming signal needs to be between the receiver and the sattelite, not always easy. Additionally, it is simple to find the jammer (just look for the GPS signal coming from the ground) and easy to counter. Finally, cheap and small INS systems largely mitigate the problem for cruise missiles and the like. Having said all that, a back-up system needs to be developed to make precision navigation more robust.

  • This could make sense, because is not the first time that someone has access to military satellites at different extent (remember talibans intercepting videos from UAV in Afghanistan or brasilian hackers accessing Navy’s satellites with home made dishes).

    On the other side, everyone knows (and recent experiments such as the Unmanned X37B prove this) that space is in a way or another the theater to govern in order to obtain a strategic advantage.

    What makes me think is how much we are relying on technology for our defense and civilian uses.

    Within the years we have shifted from tech as a commodity to tech as a vital need and this is a problem we are not thinking to solve, neither in part neither in a whole.

    A system like GPS should be safeguarded as something vital for all mankind and not be seen as a military target.

    • makatak

      hotrao (and others),

      You’re mixing up terms and capabilities here. Receiving an unencypted broadcast (UAV feeds) is not “hacking.” Using an open channel on FLTSAT is not “hacking.” Jamming a GPS signal using noise or barrage jamming is not “hacking.” All you’re doing is tuning to a signal for UAV video, taking advantage of an open satellite channel, or preventing nearby GPS receivers from receiving a sufficiently strong GPS signal to determine accurate position. For the author of the article to assert that the GPS constellation has been “hacked” is completely ridiculous. Anybody who knows anything knows that GPS jammers have been on the market and in military inventories for nearly two decades. Is that news to folks here?

  • Will

    makatak: “word” – in this case, literally

  • dan

    amen mak!