19 votes

Why does BCRYPT_RNG_DUAL_EC_ALGORITHM get removed from CNG API on Windows 10?

The Government's elliptic curve backdoor is real, isn't it? We don't know for sure, but there are indicators into that direction. More importantly though, yes, you can backdoor the RNG, as was ...
SEJPM's user avatar
  • 46k
7 votes

Does the backdoor in Dual_EC_DRBG work like that?

Not quite, but you're close. I will write $[n]A$ for scalar multiplication of the point $A$ on the curve in question by the scalar $n$, as is more typical notation, and I will write $x(A)$ for the ...
Squeamish Ossifrage's user avatar
6 votes

Mathematical proof or any reference of "Deterministic random bit generator cannot produce more randomness than the randomness of seed"

Define the Mutual Information of a pair of random variables. $$I(X; Y) = H(X) - H(X\mid Y)$$ For discrete random variables we hae that $H(X\mid X) = 0$, so: $$I(X; X) = H(X)$$ The Data-Procesing ...
Mark Schultz-Wu's user avatar
4 votes

Can the backdoor in Dual_EC_DRBG be used to create a public key stream cipher?

You can do something like what you are suggesting. But, the EC_Dual_DBRG also has biases in the stream and so you cannot use it without changes (e.g., truncating much more). However, this is based on ...
Yehuda Lindell's user avatar
3 votes

Who uses Dual_EC_DRBG?

On the Practical Exploitability of Dual EC in TLS Implementations by Stephen Checkoway et al. (Usenix 2014) is some research that has been done on how much this NSA backdoor has affected the internet. ...
David Schumann's user avatar
2 votes

Generating pseudorandom numbers using Dual_EC_DRBG

First, you need the curve constants and the P and Q points. In this example I've used P-256, but it should work similarly with secp256k1. ...
Leo's user avatar
  • 189

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