Security researcher: I found secret reprogramming backdoors in Chinese microprocessors

Sergei Skorobogatov, a postdoc in the Security Group at the Computer Laboratory of the University of Cambridge has written up claims that reprogammable microchips from China contained secret back-doors that can be used to covertly insert code:

Claims were made by the intelligence agencies around the world, from MI5, NSA and IARPA, that silicon chips could be infected. We developed breakthrough silicon chip scanning technology to investigate these claims. We chose an American military chip that is highly secure with sophisticated encryption standard, manufactured in China. Our aim was to perform advanced code breaking and to see if there were any unexpected features on the chip. We scanned the silicon chip in an affordable time and found a previously unknown backdoor inserted by the manufacturer. This backdoor has a key, which we were able to extract. If you use this key you can disable the chip or reprogram it at will, even if locked by the user with their own key. This particular chip is prevalent in many systems from weapons, nuclear power plants to public transport. In other words, this backdoor access could be turned into an advanced Stuxnet weapon to attack potentially millions of systems. The scale and range of possible attacks has huge implications for National Security and public infrastructure.

Key features of our technology:

* scans silicon/hardware for backdoors, Trojans and unexpected behaviour
* low cost
* very fast result turnaround time
* high portability
* adaptable - scale up to include many types of chip

Further funding is needed for us to progress to testing further silicon chips and to develop better search algorithms which would allow us to detect possible spy systems or vulnerabilities in a greater range of systems.

Currently there is no economical or timely way of ascertaining if a manufacturer's specifications have been altered during the manufacturing process (99% of chips are manufactured in China), or indeed if the specifications themselves contain a deliberately inserted potential threat.

This block of text is undated, though it appears on a page whose last-modified date is reported as 14-05-2012. I couldn't find any further information on which chips were affected or the methodology used to discover the backdoors.

Hardware Assurance and its importance to National Security (via MeFi)


    1. Indeed.  It’s beginning, huh?

      Witness the advance guard of  their “long range” plan-which probably will be sooner rather than later.

      1. I try never to use a disfluency “Well”, a colloquialism “reckon”, or a vulgarity “fucked”, all together unless I am absolutely certain of my statement even outside the context of the discussion. :)

      2. What? I can’t hear your suspicions as my ears are stuffed with 100 bills… 


        You didn’t think “going pee pee in your coke” was the only time they “played a joke”, did you?

    2. The Lords of The Free Market declared that the US was worthless for manufacturing, and resourced our entire damned economy to China, including our military production of microprocessors. It made Economic Sense and broke our unions, so it Was Good. They became rich. We are now helpless (think about it). Yay, let’s call in tomorrow and go out for shawarma.
      And do, please, remember this when computerized voting is discussed again. You hand a process to a magic black box, you are fucked.

      1. There are Lords of the Free Market?

        And here I thought it was just everyone buying what they want, and everyone also being cheap as $H!7.

    3. It’s OK. We’ve got backdoors into all their FPGAs, too.

      We’re all one big happy family, with our hands in each other’s back pockets. There’s a lot of covert nonsense that goes on before a shooting war, and we’ll probably be seeing this type of story for a few more years before the department of propoganda decides the public is appropriately primed and we can start shooting off fireworks. 

      I hope by then we will have gotten rid of infantry entirely, and moved to strategic robot assassinations. But, with the state of our drone tech, it’ll be a long time before we can actually replace the military with a less wasteful organization.

  1. The lesson here, I guess, is that if you’re planning on completely dismantling the electronics manufacturing capability of a country and outsourcing it to save money, you’d better pick a country that doesn’t have a track record of spying on you every chance they get.

    1. No. The lesson is not to read yellow journalism. Let me count the ways.

      “(99% of chips are manufactured in China”

      Bull-fucking-shit. This stupid statement alone should send off every single warning klaxon. First, Taiwan isn’t China. China does sizable manufacturing in older chips, but they sure as shit aren’t number one by volume, and certainly not number one by value. Even if you lump in Taiwan into “China”, it is a lot, but it still isn’t anywhere near 99%. 99% of chips might touch China at some point in their existence, but unless China has some secret technology that lets them alter chips during the grind, cutting, and packaging steps, it isn’t going to help them.

      Further, realize that the US still has substantial chip capacity and it makes good use of it. Higher end products tend to get worked on in the US. Taiwan is good for churning out crap tons of wafers for cheap. The US does some of that, but for the most part focuses on turning out smaller run products where there is no advantage of taking it to Taiwan. A lot of your military stuff falls into this column. On top of this, the US has strict rules on what government and military stuff can be made overseas.

      Finally, the guy just found that this chip could be re-programmed in an undocumented way. It could be a foreign power slipping in back doors. It also could just be someone got lazy. I wouldn’t rule out an attempt to put in a backdoor, but I wouldn’t jump to conclusions either. It could be that the it was the US government put the backdoor in the chip. It isn’t like we don’t export military parts.

      Is there a legit threat from China and other powers that they are putting in backdoors? Sure. We are almost certainly doing the same to them, and seeing as how the chips are designed in the US, it is a hell of a lot easier. That said, all of these nations realize getting into that kind of cyberwar isn’t going to be fun. On top of that, all nations involved recognize the threat and so go domestic for most critical things.

      Frankly, if the US gets into a shooting war with China, I am pretty sure that a few re-programmable chips will be pretty far down on the list of worries for both nations.

      1. This kind of sloppinness has been going on for years.  A long time ago it was revealed that the Air Force uses ‘grade 8’ fasteners from China.  Testing proved that they weren’t much better than ‘grade 5’ if at all.  Lowest bidders win the contracts.   Tracing of the bolts makers also showed that a lot of these alleged ‘grade 8’ fasteners were used by domestic airplane manufacturers.  And, oh, no, they wouldn’t allow poison to be added to baby formula, either.  And toothpaste.  Not to sound paranoid, but we’ve been around this bush many times before – originally with domestic manufacturers before the government got on their backs and forced them to conform to standards.  Soon there will be a litany of Americans-in-China entrepreneurs saying that we should get off the backs of foreign providers.

      2. Good analysis. I would also add that discovering a “problem” with China’s manufacturing seems quite convenient in the current recession given that the US would like to erect trade barriers again.

        1. Not really.  You might see a talking point here or there, but isolationism, contrary to Ron Paul’s vivid imagination, is really a thing of the past.  

          It’s pretty simple: the wealthy who have more incentive to keep the global trade flowing are more power than the wealthy who have the opposite incentive.

    1. Let’s hope not lol, after all if it is widespread, prevalent, then the Chinese response to that question might be a tentative “yes?”.

      After all, no amount of sabre-rattling will accomplish much if the other party knows you can’t get it out of the scabbard.

      May it all come to naught, with manufacturers apologizing, chips getting switched, some jobs coming back to North America and a not-too embarrassed Chinese govt. handing olive branches to a very justifiably embarrassed Western alliance.

      I mean, we’re talking about a nation that may be content to wait a hundred years to get it right, maybe a thousand. 

    2.  How so?  It’d be like saying you can kill someone for selling you a defective product.  They shouldn’t have bought from China in the first place, especially since we did the same thing to the USSR with regards to chips for pipeline controls.

    3.  How do you know that this backdoor isn’t merely to spec? It’s entirely plausible to me that it might be as having it in such a common component with widespread use in a variety of systems would be very handy. And of course the existence would be classified highly so one wouldn’t expect it to be documented publicly or even to end purchasers. Until now (and maybe even now), people who publicly theorized about the possibility (or even probability) of such backdoors have been routinely cast as the tin-foil hat crowd or even lunatics. Secrecy makes this possible.

    4. It doesn’t need to. A funny look seems to constitute an act of ‘police action’ these days, and it’s the same thing aside from the matter of congressional approval.

      Normal diplomacy by normal means, &c.

    1. Just as suspicious as a person whose last name is “Goldberg” working in banking.
      Skorobogatov is a fairly common Russian last name. Sorry to torpedo your theory.

    1. I always figured they were doing this.  And that we’re doing it too with chips we make here in the good ole US of A.  I mean, if you want tamper proof, you’ll need to control ALL levels of design and production.  You can’t expect anyone else to have your security interests at heart.

      1. Well, it’s true. Everybody does it.

        Hell, Intel puts out CPUs that can be shut down by remote control. That’s much worse than FPGAs that can be reprogrammed by someone who has managed to extract them from military hardware and doesn’t happen to have the vendor key!

    1.  Thanks for your analysis.  It makes the original story sound like yellow journalism.  Its not at all unusual for a FPGA to have a “back door”.

  2. … an American military chip that is highly secure with sophisticated encryption standard, manufactured in China.

    That makes a lot of sense.

  3. It’s a good thing that Sergei Skorobogatov is living in the UK.  And he’d better stay away from the USA, otherwise he would have to be charged under the DMCA.

  4. This should not be surprising t anyone. least of all the American military who have been talking about this kind of idea for years. The game it reminds me of most is not Red Alert but Black Ops 2. Imagine a fleet of hijack-able drones, maybe this is currently possible.

    1. Our drones are already hijackable. Don’t you recall all the news stories about how the video streams were entirely unencrypted and Afghani civilians were watching the view from the nose? I’m not convinced that the control channel for these armed RC planes are much better.

  5. I can’t believe it Jim, that girl is standing over there and you’re telling him about our backdoors.

  6. 99% of chips made in China? I find that hard to believe. Taiwan, Korea and Japan were still the major front-end manufacturers last time I looked. Maybe 99% of back-end (i.e singulation, wire-bonding and final packaging) is done in China (I doubt it though) but that’s not where you’re going to be able to insert secret back-doors.
    I work for a semiconductor equipment manufacturer and we do have customers in China but not that many.

    1. Taiwan is PRC, and foundries there operate solely with the blessing of the PRC. It, and mainland China, are excellent places to insert logic — copy and alter the mask, insert additional mask steps, or just alter the description files if the customer contracted for etch mask production services, too. All it takes to cover failed attempts to tamper, is to say that the design failed at 3% rate.

      1. “Taiwan is PRC”

        I think most Taiwanese would disagree with that assertion. At least, the ones I know would.

        1. I would disagree with it, as well, except that it’s trivial for the PRC to impound, confiscate, harass, seize, and control import-export from / to Taiwan. Because of that, for our intents and purposes, it’s PRC.

        2. “I think most Taiwanese would disagree with that assertion” – to the point of maintaining a substantial military, in fact.

  7. My gut instinct tells me this ‘backdoor’ may be how the chip is loaded with firmware in the first place, and the mistake is that the master key isn’t closed so as to ensure that the chip functions only as a ROM.  The chip may have inherited this flaw from a consumer firmware design, where having this sort of thing is a useful feature, or the flaw intentionally exists as a feature without consideration as to its impact. 

    Overall, it’s far more likely that the manufacturer is lazy and incompetent as opposed to having nefarious intent.  Unfortunately, that doesn’t make the situation any more comforting.

    1.  It’s a military chip, and the chip was most likely developed in the US, not in PRC. The Chinese most likely only got the blueprint file and order to produce it.

      So either they changed the blueprint (nefariously) or the incompetents are sitting in the US.

      1. Why would the schematics be produced domestically? After all, it’s not just manufacturing that’s cheaper in China.

        Clearly, we should outsource our military to China and be done with it. It would prevent americans from being wounded in american wars, after all.

    2. The silicon in question is a field-programmable gate array : FPGA. It’s a series of gates that can be programmed via a file to be, effectively, any ligic you want.

      There is a dedicated piece of silicon that controls access to reprogramming the gate array. It has asecret key provided by the vendor, that authenticates the attempt to reprogram.

      What tjis man has discovered is that there is a separate key, and separate logic, than what is documented, that will allow for reprogramming. This could be as sophisticated as the original or it could be incredibly simple. Or it could be yet-another-authentication-key, inserted by the manufacturer at or before the vendor’s key was inserted.

  8. What they did is called side-channel attack. It’s fairly well documented. Their quantum leap forward was through removing a VERY expensive oscilloscope (a general-purpose device, for our discussion) and crafting circuitry specific to the silicon they’re analysing.

    This involves two methods:

    Throwing random and quasi-random instructions and external signals at the chip, comparing those against what one would expect, putting an electronic “stethoscope” on the chip. Refine and iterate. Sounds like what they did.

    Fabless semiconductor agencies — the ones who ship their chip specs to Taiwan and the mainland for manufacture — have been aware of the possibility of backdoors and extra logic being introduced at manufacturing time (or at least the potential for this) for at least six years. The US government became aware twenty years ago (aka Why was software crypto suddenly demilitarised and clipper chip technology initiatives dropped circa 1992).

    And if the Chinese government can do this, by altering the SPICE model or chip mask provided to a chip foundry, then the US Government can certainly do it by sitting down with the original EEs that designed the chip. So, what they’ve discovered could just as easily be the efforts of any government.

    How they discovered the backdoor is far more important than the fact that they found a backdoor. Yes, a backdoor in this silicon is going to be a multi-million hassle for whoever is using it. The ability of an EE to build, in a week, an adaptor to audit a chip-and-pin bank card or an iPhone ADC or radio processor, extracting the shared, embedded, encryption and authentication keys held therein – WAY more important.

    Possible results: Media encryption master keys being recovered for storage, decryption, and transmission methods. Financial instrument update keys being recovered (the keys that let the vendor update your personal keys in the device). Financial transaction systems being compromised.

    Oh, and the ability of some yokel EE somewhere to find the magic sequence that turns off the power for the Eastern Seaboard.

    Everything is made by the lowest bidder, to skim the most profit.

    1. Armageddon:

      You know we’re sitting on four million pounds of fuel, one nuclear weapon and a thing that has 270,000 moving parts built by the lowest bidder. Makes you feel good, doesn’t it?

      Lev Andropov:
      [annoyed] Components. American components, Russian Components, ALL MADE IN TAIWAN!

    2. Software crypto is still a munition, of course.

      Not that it’s enforced. I suppose they’ll use it when they find somebody they want to lock up who can’t be pinned on any legitimate charge, and who has used encryption to talk to some machine overseas or exported an igpay atinlay text filter or something.

  9. Im not sure if other commenters are being sincere in their apparent belief in this “article” but I call bs. The posting is essentially a a sales pitch, and as the author’s homepage says “My research grant was extended several times and it is currently until the end of 2012, therefore I am always looking for interesting and beneficial projects which could provide funding for my ongoing and future research.”

    If he had made a discovery of such import, it wouldn’t have been announced like this, and he wouldn’t likely be a research associate with no particular credentials, as a google search quickly reveals, and certainly wouldn’t need to make vague, public funding appeals via his web page.

    1. I had the same thought. It sounds like an attempt to cash in on the paranoia market.

    2. To quote user tptacek (probably Thomas Ptacek, someone who is himself very much not fucking around when it comes to security), over on the THN thread Alex Young linked above – “The Cambridge Security Lab is not fucking around. Assume this is not hype.”

  10. Not an EVIL BACKDOOR, normal feature to enable acces to bricked chips. HDDs also have master passwords that override user password (and no doubt there is another secret one that overrides master one :P)

    1. Evil is unlikely, but the problem is that the master key was easily retrieved from the analysed chip.  If this master key is consistent across all the chips (and that is likely), then they can all be broken without physically tampering with the hardware.  That is a serious fault.  Also, the master key(s) are known to a company that is under the jurisdiction of a foreign superpower that is engaged in covert operations against the US.  This makes this a particularly major blunder.

      If the chips were properly write-protected, there wouldn’t be an issue because there would be no way to reprogram them irrespective of whether you have the key or not.

      1. It’s an FPGA.  It’s designed to be reprogrammable. It wouldn’t be “field programmable”  if it weren’t.

      2. Everybody is in covert operations against the US. That’s what you call an ally: someone who doesn’t engage in overt operations against you, and so instead limits themselves to covert operations!

        Keep in mind that a large portion of being covert is flying a false flag. If something seems to come from China, it is just as likely that it comes from (say) Israel or the United Kingdom, or even (gasp!) domestically.

  11. The description is rather vague, but alludes to the ability to modify the contents of an FPGA whose programming bitstream is encrypted for anti-reverse-engineering purposes. To do this, you’d need to have physical access to the chip.

    Unless, of course, the chip (which can include an FPGA implementation of an ARM processor) is connected in such a way as to be remotely reprogrammable, in which case you reap what you sow. Secure systems are not remotely reprogrammable!

    As an engineer, I think that the text was written for Nervous Nellie management types rather than for engineers. I also think that if secure military systems are being designed with remote-reprogramming connections, then the military security is now an oxymoron.

    1. It’s not that it’s remotely reprogrammable — it’s that the key retrieved by access to ONE FPGA, is usable on every other FPGA of the type.

    2. While remote programming of FPGAs is still ludicrous (so far as I know), at least some military security systems are indeed a joke. Some varieties of fighter jets have onboard instrumentation networks that are, quite literally, unencrypted wifi. We all know precisely how insecure *encrypted* wifi is, and how easy it is to perform a man-in-the-middle.

      This is to say nothing of a rumour I heard about five years ago that some naval installations had to downgrade their machines to Win98SE on account of some higher-up who insisted upon transmitting orders via Microsoft Comic Chat.

      Let’s just say that there are people who make decisions on subjects upon which they lack the competence to decide, and that the military seems to be no more immune to sturgeon’s law than any civilian organization.

  12. Or the backdoor is by design (US), keeping in mind that the military equipment would also be sold (by the US) to other countries. Take a look at the Malvinas/Falkland war and how the British requested  codes from the French government  in order to disable the Argentinian (French-made) Exocet missiles. The French refused for a while, but then agreed when the British threatened to use nuclear weapons.

    In other words: your billion-dollar army is as good as until you actually have to use it against one of the manufacturer’s buddies.

    1.  This reminds me Krupp, a German manufacturer of steel, armaments and ammo. Family owned for 400 years. Sure, they had absolutely no problems about selling weapons to Germany’s enemies. They just made certain that Germany always had the best of what they built. Check out ‘The Arms of Krupp’ by Wm. Manchester. Fascinating book.

  13. One kind of attack to mount upon those in which you wish to instill fear and dread is to cast doubt upon their security in a way that cannot quickly or easily be demonstrated false. Does this remind you of anything else?

    Of course this doesn’t mean that the military, or your own civilian population (just for the sake of argument), isn’t under a real threat. But, y’know … just sayin’.

  14. The statement that “99% of chips” are manufactured in China” is simply ludicrous and calls into question the credibility of the entire “research” article.   Seems that all anyone has to do to get into people’s (or government’s) wallets  is appeal to the paranoids and conspiracy theorists anymore.   

    1. Taiwan is a relatively small island (group), with tea fields and residences. Mainland (prc) doesn’t have the premium on real estate. Most taiwanese foundries are on PRC soil.

      99% may not be accurate, but it is within five percent. The other major foundry players are, in descending order of volume, Japan, the US, Israel, and russia.

      1.  Didn’t you make the claim upthread that since China can interfere with Taiwanese trade, foundries on Taiwanese soil are de facto PRC? Now you say the foundries aren’t in Taiwan at all. Would you care to choose a position and stop contradicting yourself?

  15. I actually don’t have a problem with China putting backdoors in chips they manufacture. Good idea, especially if it’s something we’ve done in our own weapons systems. Weapons systems made in China should really be considered joint Sino-American projects. If we want our ultra high-tech military to be secure, we should make it ourselves.

    1. We do. The CIA and other TLAGAs own or operate “private” enterprises that close the supply chain on particularly blessed secure systems. The difficulty there is, they have to deal with all kinds of problems, such as meeting EPA regulations (or avoiding detection of having violated them), hiding their revenue and capital, and not capitalising on efficiencies of scale. Oh, and the interminable retools and respins to meet not just the laws of physics but also DOD regs.

    1. China is not an enemy of the United States any more than you are the enemy of your landlord.

      For instance, you might criticize your landlord’s response time when the pipes leak, but you are fairly unlikely (unless you are a dangerous psychotic) to kill his children.

  16. No surprise here – I was told by a high-ranking civilian engineer at a U.S. military installation that an entire batch of military-issue secure thumb drives were discarded (and I imagine destroyed) because they found backdoors built in by the Chinese manufacturers. This was at least a year ago, maybe more, IIRC.

  17. Those ‘backdoors ‘ are probably just test modes that could be used to crash a digital device but not too useful for changing firmware or instructions.

  18. My bet would be that some idiots who want to just see the world burn would be the first to trigger them. “Look, Ma. I caused some cataclysmic havoc!” The maj0rity of these things probably wound up in industry & the public sector, and the havoc will be isolated to Hondas rolling off of Southern assembly lines with Grateful Dead lyrics stamped into their bodies.

  19. I don’t believe it until it’s independently verified but I guess it’s gotten to the point that I can’t trust a chip that I haven’t programmed myself.

    1. Opencores is still around, last I heard. A lot of forth machines there; not sure if there’s much else of interest. 

      The problem, of course, is that ONLY hackers are interested in them. So, they have approximately the same effect upon the everyday life of non-hackers as AmigaOS and DragonflyBSD do (and less than OS/2, which at least still runs ATMs!)

  20. Thanks to my Critical Reading professor for teaching me how to scan an article with a critical eye:

    ~”We chose an American military chip that is highly secure with sophisticated encryption standard”.
    ~”We scanned the silicon chip in an affordable time”.
    ~”Further funding is needed”.
    ~”Currently there is no economical or timely way”. 
    ~”This particular chip is prevalent in many systems from weapons, nuclear power plants to public transport.”

    Also, I live in Phoenix Arizona, so I question the 99% claim. Recently “President Obama visited a Phoenix suburb to tour Intel’s still-under-construction computer chip manufacturing plant. Its price tag – $5.2 billion – making it the largest construction project in the world outside this summer’s London Olympics.”


  21. Those of us who still remember the 90s will recall that back when the US was manufacturing its own encryption chips, there was a government push for key escrow (tantamount to giving the NSA a spare copy of every cryptographic key used by any US citizen using encryption hardware). Compared to that, the idea that there’s a testing interface in military encryption chips intended to be used in airgapped systems is fairly tame.

    In other words, this story is nothing to be concerned about.

    Had these chips been manufactured in the United States, they would also have ‘backdoors’ like this (probably JTAG-compatible!). The difference is that the Chinese chips are cheaper and actually up to spec.

  22. “an American military chip that is highly secure with sophisticated encryption standard, manufactured in China”

    National security.  You’re doing it wrong.

  23. The trick about security is not to tell anyone about it. Sending secure items to a foreign power to be manufactured is probably not a good idea. I’m still amused by a couple of incidents in Britain’s past related to back doors etc. The breaking of the Enigma machine was a top secret after the war because we sold machines to friendly nations and didn’t want them to know we could read their secrets. Similarly RSA doesn’t have a patent in the UK because we invented it first and kept quiet until 1998. So if China is putting back doors in silicon manufactured over there then its far from surprising and quite funny. What would they expect would happen?

    If you want really secure then electronic security isn’t enough. You need physical security, eg locked rooms, epoxy over parts, burning out the reprogramming section of chips…

  24. Surprise! 

    Why aren’t there fish anymore? Why don’t our weapons work? Why are there no jobs? Why are they trying to kill us? Why do they hate us? Why Why Why? 

    How wonderful for the US and it’s people – life is full of surprises!

  25. China is not a friendly world power and has not been for many years. While the US government has become far more authoritarian  in the last decade, it pales to a shadow of the extremity of the Chinese government.

    In 1989 the Chinese military ran tanks over peacefully demonstrating students. It didn’t pepper-spray them or arrest them or make them feel bad. Under specific government instruction, the Chinese military murdered Chinese citizens for defying their government.

    The Chinese government has tried and executed people for sending spam.

    The Chinese government will arrest and forcibly perform abortions on women if they try and give birth to more than their one alloted child.

    Before you dismiss the concerns about handing over our entire supply chain process to a nation that is, for all intents and purposes, sociopathic and perhaps psychopathic, please read up on the history of China in the past 50 years. China is far, far more dangerous to the US than any number of terrorists or the whole of Islam.

    1. Yeah, but they have nukes and money so we’re not going to mess with them.

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