Going back to 2007 and a seminal presentation at the CRYPTO conference by Dan Shumow and Niels Ferguson, there have been suspicions about Dual EC DRBG primarily because it was backed by the National Security Agency, which initially proposed the algorithm as a standard. Cryptographer Bruce Schneier wrote in a 2007 essay that the algorithm contains a weakness that “can only be described as a backdoor.”
“I wrote about it in 2007 and said it was suspect. I didn’t like it back then because it was from the government,” Schneier told Threatpost today. “It was designed so that it could contain a backdoor. Back then I was suspicious, now I’m terrified."
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