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Are the NIST Standard Elliptic Curves Back-doored?

IamTheRealMike writes "In the wake of Bruce Schneier's statements that he no longer trusts the constants selected for elliptic curve cryptography, people have started trying to reproduce the process that led to those constants being selected ... and found it cannot be done. As background, the most basic standard elliptic curves used for digital signatures and other cryptography are called the SEC random curves (SEC is 'Standards for Efficient Cryptography'), a good example being secp256r1. The random numbers in these curve parameters were supposed to be selected via a "verifiably random" process (output of SHA1 on some seed), which is a reasonable way to obtain a nothing up my sleeve number if the input to the hash function is trustworthy, like a small counter or the digits of PI. Unfortunately it turns out the actual inputs used were opaque 256 bit numbers, chosen ad-hoc with no justifications provided. Worse, the curve parameters for SEC were generated by head of elliptic curve research at the NSA — opening the possibility that they were found via a brute force search for a publicly unknown class of weak curves. Although no attack against the selected values are currently known, it's common practice to never use unexplainable magic numbers in cryptography standards, especially when those numbers are being chosen by intelligence agencies. Now that the world received strong confirmation that the much more obscure and less widely used standard Dual_EC_DRBG was in fact an NSA undercover operation, NIST re-opened the confirmed-bad standards for public comment. Unless NIST/the NSA can explain why the random curve seed values are trustworthy, it might be time to re-evaluate all NIST based elliptic curve crypto in general."

19 of 366 comments (clear)

  1. Meta review by pr0nbot · · Score: 5, Interesting

    As well as reviewing the standards themselves, I hope someone is reviewing the processes which allowed these weaknesses to get into the standards.

    1. Re:Meta review by FriendlyLurker · · Score: 5, Insightful

      it's common practice to never use unexplainable magic numbers in cryptography standards, especially when those numbers are being chosen by intelligence agencies.

      Well then, how do we explain the common practice of using magic numbers in cryptography standard, then?

      As well as reviewing the standards themselves, I hope someone is reviewing the processes which allowed these weaknesses to get into the standards.

      Exactly. A list of people had to be complicit in getting these "magic backdoor" numbers into the standards. The integrity of these people is now highly questionable, and they should be put to task over the issue, removed from decision making posts and in the worst cases, professionally shunned by the community and excluded from all standards processes... the cost of not doing this is a return to business as usual once things settle down.

    2. Re:Meta review by Anonymous Coward · · Score: 5, Funny

      So I can just replace the NSA's magic-numbers with my own generated from RdRand! *ducks*

    3. Re:Meta review by afidel · · Score: 5, Informative

      Suspicious yes, but not necessarily bad, remember that the NSA also manipulated the s-box values for DES to make them more resistant to differential cryptanalysis, a technique not yet known by the wider community.

      --
      There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
    4. Re:Meta review by postbigbang · · Score: 5, Interesting

      Even when pi or rho or other "random" numbers are used for seeds as "magic" numbers, additional hashing and rehashing is needed to give further difficulty to decryption by those NOT having the key numbers.

      With each new algorithm there is an army chomping at the bit (pardon the pun) to decrypt it, if not for fun or enlightenment, for the profit of the decrypted information value-- if any.

      The problem here is trust. The NSA has blown its trust completely, beyond identifiability. Other initiatives, like SELinux, and security initiatives are now also in question, as well as anything the NSA has touched. They're dirty, and make Americans and the world not trust in their own government. We were supposed to be the good guys, we Yanks, and guess what? It was all a lie. Now the NSA has made an enemy of civil people, and civil people will need to protect themselves extra-governmentally, because the government has proven it's not protecting the interests of its citizenry.

      Sorry to astroturf, but seeds are no longer the problem. The problem is trust.

      --
      ---- Teach Peace. It's Cheaper Than War.
    5. Re:Meta review by Carewolf · · Score: 5, Informative

      Iranians are NOT semitic, they are Aryan, the name Iran literally means home of the Aryans. Named so because that is the one common thing that separates the various Iranian people from their semitic neighbours the Arabs.

  2. We owe our thanks to Mr. Snowden by Taco+Cowboy · · Score: 5, Insightful

    ... A list of people had to be complicit in getting these "magic backdoor" numbers into the standards. The integrity of these people is now highly questionable

    This, and many other expose, can only come to light, because of the courage of a single person - Mr. Edward Snowden.

    If not for Mr. Snowden, would we ever discover the phenomenon of the "magic number" ?

    If not because of Mr. Snowden, we wouldn't even begin to question the integrity of those previously highly regarded "very important people".

    If not for his courage, how much more damage all of us have to suffer ?

    And yet, inside the United States of America, there are still people equating Mr. Snowden as though he is a traitor.

    And even here in Slashdot, we have posters posting very stinging attack on Mr. Snowden.

    Our country is under attack, and the attacker is our own government, but yet, there are still Americans who will do everything to help deepen the tyranny, all in the name of "patriotism".

    I, an American citizen, do owe my deepest thanks to Mr. Edward Snowden, and I do hope that more of my fellow Americans should start acknowledge something very very wrong has happened to America, the country we love so much, and that we should start doing something together, to RIGHT THE WRONGS.

    There have been too many comments that essentially convey the message that we, the People of America, have no power to determine our own future, and that our government, is so overwhelmingly powerful that we are ready to become their slaves, rather than stand up and oppose the tyranny.

    Is America still the land of the free, and the home of the braves ?

    Or has American turned into the land of the enslaved, and the home of the cowards ?

    The choice is on your hand, my fellow Americans.

    Either we start righting the wrongs now, or we will end up handing over to our children a country of tyranny.

    Are we going to let our children suffer because of our cowardice ?

    You are the only one who can answer the question.

    --
    Muchas Gracias, Señor Edward Snowden !
    1. Re:We owe our thanks to Mr. Snowden by j3thr0 · · Score: 5, Informative
      --
      I'm schizophrenic; no I'm not.
    2. Re:We owe our thanks to Mr. Snowden by rvw · · Score: 5, Insightful

      Except that this came to light back in 2007.
      http://www.wired.com/politics/security/commentary/securitymatters/2007/11/securitymatters_1115

      So why has nobody fixed this in the past six years? Thanks to Snowden it's back in the spotlight, and now it seems like action is being taken. That's his legacy. I thank him for that.

    3. Re:We owe our thanks to Mr. Snowden by IamTheRealMike · · Score: 5, Informative

      That story is about Dual_EC_DRBG which was indeed strongly suspected of being an NSA back door back in 2007. Snowden confirmed the suspicion. However this story is not about that algorithm. It's about the SEC random curves that are used for signing and other crypto, not random number generation. There are two different algorithms under discussion here.

    4. Re:We owe our thanks to Mr. Snowden by lkcl · · Score: 5, Insightful

      if you've seen the film with nicholas cage, it highlighted for me for the very first time that the U.S. Constitution was written by some extremely fore-sighted people. there are specific words in it which not just permit but *OBLIGATE* you - each and every american citizen - to overthrow any government that has become tyrannical or otherwise lost its way.

      given that america has such a significant hold over the rest of the world, *i* as a UK citizen am obligated to point this out to you, because by not doing so it will have an adverse effect (through erosion of sovereign rights of each and every country - erosion initiated by the corrupt U.S. Govt infrastructure) on *my* country to whom *i* hold allegiance.

      so - get to it, americans - get your act together!

    5. Re:We owe our thanks to Mr. Snowden by Anonymous Coward · · Score: 5, Insightful

      Before it came to light as a theoretical possibility. People could see that the possibility existed, however accusing the NSA of having used it would be accusing them of deliberately and knowingly weakening the security of systems designed to be used in defence of their country. That is a pretty serious accusation against people who essentially work for the military. Most people's belief in innocent until proven guilty made that a hard case to make.

      Now, thanks to Snowdon, we know they have been weakening system security for their own convenience. Suddenly many people's old viewpoints have become obviously naive.

  3. Re:Reference? by IamTheRealMike · · Score: 5, Informative

    Sorry, I could have provided a link for that too. It was in the major Snowden story of last week that revealed the NSA was undermining public standards. The New York Times said this:

    Simultaneously, the N.S.A. has been deliberately weakening the international encryption standards adopted by developers. One goal in the agency’s 2013 budget request was to “influence policies, standards and specifications for commercial public key technologies,” the most common encryption method.

    Cryptographers have long suspected that the agency planted vulnerabilities in a standard adopted in 2006 by the National Institute of Standards and Technology and later by the International Organization for Standardization, which has 163 countries as members.

    Classified N.S.A. memos appear to confirm that the fatal weakness, discovered by two Microsoft cryptographers in 2007, was engineered by the agency. The N.S.A. wrote the standard and aggressively pushed it on the international group, privately calling the effort “a challenge in finesse.”

    “Eventually, N.S.A. became the sole editor,” the memo says.

    Although the NYT didn't explicitly name the bad standard, there's only one that fits the criteria given which is Dual_EC_DRBG.

  4. Re:Why is EC more secure than RSA? by Anonymous Coward · · Score: 5, Informative

    The number field sieve relies on the smoothness of the integers modulo n. Using an elliptic curve group rather than the integers modulo n removes this smoothness, so the fastest algorithms available to determine the discrete logarithms are much slower (I believe they're based on Pollard's rho algorithm).

    If that made no sense to you, go brush up on your number theory.

    If you don't want to learn number theory, then accept that you are incapable of having an informed opinion on asymmetrical cryptography standards. (Which is okay, we can't all have an informed opinion on every issue; your brain can only hold so much stuff, right?)

  5. Justified paranoia by return+42 · · Score: 5, Insightful

    I think we are all going to have to be a lot more paranoid from now on about the public comments NIST gets on crypto standards. We can count on NSA to continue to try to mess with the standards, but they won't do it openly. They'll use proxies with no traceable connection to NSA. The crypto experts will have to examine these things a lot more carefully. Hanlon's razor won't cut it anymore.

  6. Not paranoid *enough* ? by pla · · Score: 5, Interesting

    I only see people discussing the first-level implications to privacy and security of the NSA having chosen parameters that lead to a somehow-weak curve. Except - That doesn't take any special NSA magic, they just cheated up front.

    Such discussion completely overlooks the much bigger problem here, however - The NSA chose parameters that give a weaker curve. Parameters generated as the output of hashing them with SHA1.

    The ability to choose parameters strongly suggests that the NSA has a way to produce input texts that yield a desired SHA1 hash. That takes special NSA magic, and should really count as the FP story here, not the far less impressive trick of stacking the deck in their favor.

  7. Re:Why is EC more secure than RSA? by lordlod · · Score: 5, Interesting

    The elliptic-curve algorithm is much slower for future quantum based attacks. So it's future-proofing, which is required if you want your secrets to stay secret.

    You could get similar results by adopting a 15000 bit RSA key... but that's getting rather large.

    A paper with some classical and quantum time estimates, Elliptic-Curve vs RSA: http://arxiv.org/pdf/quant-ph/0301141v2.pdf

  8. They know me by Taco+Cowboy · · Score: 5, Insightful

    Thank you Mr. Taco Cowboy (if that's your real name). The FBI should be visiting soon. Please hide your dogs, for their own sake.

    Almost every single time I posted a comment that hits the bull's eye someone would counter it with a veil threat, like the above.

    FYI, they know who I am.

    I came from China, I am a naturalized citizen of the United States of America, and I am currently not living inside the U.S. of A.

    In my younger days, I also was involved in some (still secret) military programs.

    They have my dossier. They know where I am.

    If they want to take me down, they can, any time.

    But I am not important. I am expendable.

    What is important is the future of my country, the United States of America.

    As I said, I came from China, I had had first hand experienced the terror of Tyranny, with a capital "T".

    What I, and millions of my former comrades in China had suffered through, I would NOT want you guys in America to go through.

    The terror of Tyranny is much more than any Hollywood movie could ever convey.

    Go ahead, threatening me more, if that is the thing that makes you feel good.

    I have gone through the baptism of hell back when I was in China, death is nothing to be afraid of.

    As I said, I am expendable, but the United States of America is not.

    --
    Muchas Gracias, Señor Edward Snowden !
  9. Re:hmmm by joe_frisch · · Score: 5, Insightful

    I think that American users have more to fear from US government spying than foreign users do. Frankly I don't care if the Chinese government has access to all of my personal data - they have very little ability to or interest in interfering with my life. The US government on the other hand is much more likely to act against me in response to my (hypothetical) online mis-behavior. In the same way Chinese citizens have little to fear from the US government but a lot to fear from their own.

    The very important exception to this is when you are dealing with industry trade secrets it is quite possible that foreign governments with links to industry represent a larger threat than your own. Of course while the NSA as an organization almost certainly does not sell trade secrets that they have obtained, it is possible that individuals working for the NSA might do so. Snowdon stole a bunch of information and turned it public, another man in the same situation might well have sold it.