From a recent NY Times article:

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.

What protocol was adopted by NIST in 2006, then subsequently broken by MS employees in 2007?

  • 1
    $\begingroup$ Somebody claiming to be John Kelsey of NIST says that NSA did not write SP 800-90. $\endgroup$ Sep 9, 2013 at 7:29
  • $\begingroup$ It wouldn't be the first time the media got something wrong; even the NYT makes technical mistakes occasionally. More likely, there is a wrong perception among researchers about the history of SP 800-90. $\endgroup$
    – Fixee
    Sep 10, 2013 at 3:16

1 Answer 1


The standard in question was the Dual Elliptic Curve Deterministic Random Bit Generator (Dual_EC_DRBG), standardized in NIST Special Publication 800-90. In this case, it was not a protocol, but instead a random number generator. It wasn't exactly "broken"; instead, it was proven that there existed a "master key", if you will, that would allow someone to predict the stream of "random" bits. (That is, the PRNG isn't really random if you happen to know the proper numbers.)

Despite that the cryptography community has been aware of this for some time now, this discovery has resurfaced in the recent media firestorm surrounding the Snowden leaks. Note that we aren't really sure if the NSA really constructed the backdoor, or if they have the backdoor "key", although recent events seem to suggest that they do.

You can find some more information at these links:

and of course, the citations at the bottom of the above-linked Wikipedia article are always nice to look at.

  • $\begingroup$ While that's an obvious candidate for a rigged standard, it's not completely clear if it's the standard the article was talking about. $\endgroup$ Sep 9, 2013 at 7:31
  • 2
    $\begingroup$ @CodesInChaos: I'd be surprised if the article was referencing another standard. Look at the criteria and how closely they align: Dual_EC_DRBG was published in 2006, it was standardized by ISO, two Microsoft cryptographers found the vulnerability, and the vulnerability was published in 2007. I suppose it could be talking about another construction, but I very much doubt that many other constructions fit those specific criteria. $\endgroup$
    – Reid
    Sep 9, 2013 at 13:22
  • 3
    $\begingroup$ @CodesInChaos: NYT confirmed that it was Dual_EC_DRBG they were talking about. $\endgroup$
    – Reid
    Sep 11, 2013 at 5:03
  • $\begingroup$ @Reid: I think adding this ^^ reference would improve your (already good) answer $\endgroup$ Nov 10, 2013 at 13:42

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.