> Most cryptographers would still recommend the hybrid over pure ML-KEM. This RFC (for pure MLKEM) is marked "recommended to implement = N". It is purely for settings where the implementors independently want to use pure ML-KEM for some reason.
That's exactly how it was with Dual_EC_DRBG.
E.g. https://www.schneier.com/essays/archives/2007/11/did_nsa_put...
I don’t understand why the NSA was so insistent about including Dual_EC_DRBG in the standard. It makes no sense as a trap door: It’s public, and rather obvious. It makes no sense from an engineering perspective: It’s too slow for anyone to willingly use it. And it makes no sense from a backwards-compatibility perspective: Swapping one random-number generator for another is easy.
My recommendation, if you’re in need of a random-number generator, is not to use Dual_EC_DRBG under any circumstances.
So most cryptographers _recommended_ staying the hell away from Dual_EC_DRBG. But hey, harmless, no one serious about security would actually use it right?Except as we know now, after the standardization NSA was able to persuade/bribe vendors to implement it.
RSA is still a viable cryptography vendor, after accepting money to backdoor their product for paying customers. The standardization gave them a fig leaf of plausible deniability. Honest mistake, could happen to anyone, right? If they had needed to implement a "non-standard" backdoor, or if it had been officially struck from the standard, it would have been a lot harder to row away from.
there has been no hint of a backdoor in ML-KEM. In fact, it (and every lattice-based scheme) has been made less efficient on purpose to rule out the only possible backdoor (the ephemeral "a" part in LWE-type samples could be fixed/standardized to something. There are plausibly some mild savings associated with this. Every "real" LWE-type scheme since the New Hope scheme, deployed in Chrome a decade ago, has chosen not to do this out of an abundance of caution).
For DUAL_EC_DRBG, the mechanism that could yield a backdoor was known pre-standardization. To get the backdoor RSA had to specifically use government chosen parameters.
These are not new concerns. If even a candidate backdoor had appeared in ML-KEM (similarly to how DUAL_EC_DRBG was), it would be a very different story. But nobody has ever even suggested something might be off!
So no, it's not exactly the same as DUAL_EC_DRBG. Different things are in fact different. Note that there are similarities to DUAL_EC_DRBG in contemporary cryptography. Russia has a block cipher Kuznyechik that has some very fishy structure in its S-box. We don't know how such structure is exploitable, but I would bet money that it is. Despite not being able to see an attack, we can see that things seem off in a concrete way. Nobody has *ever* suggested that for ML-KEM.