Matthew Sparkes reports via NewScientist: A prominent cryptography expert has told New Scientist that a US spy agency could be weakening a new generation of algorithms designed to protect against hackers equipped with quantum computers. Daniel Bernstein at the University of Illinois Chicago says that the US National Institute of Standards and Technology (NIST) is deliberately obscuring the level of involvement the US National Security Agency (NSA) has in developing new encryption standards for “post-quantum cryptography” (PQC). He also believes that NIST has made errors — either accidental or deliberate — in calculations describing the security of the new standards. NIST denies the claims.
Bernstein alleges that NIST’s calculations for one of the upcoming PQC standards, Kyber512, are “glaringly wrong,” making it appear more secure than it really is. He says that NIST multiplied two numbers together when it would have been more correct to add them, resulting in an artificially high assessment of Kyber512’s robustness to attack. “We disagree with his analysis,” says Dustin Moody at NIST. “It’s a question for which there isn’t scientific certainty and intelligent people can have different views. We respect Dan’s opinion, but don’t agree with what he says.” Moody says that Kyber512 meets NIST’s “level one” security criteria, which makes it at least as hard to break as a commonly used existing algorithm, AES-128. That said, NIST recommends that, in practice, people should use a stronger version, Kyber768, which Moody says was a suggestion from the algorithm’s developers.
NIST is currently in a period of public consultation and hopes to reveal the final standards for PQC algorithms next year so that organizations can begin to adopt them. The Kyber algorithm seems likely to make the cut as it has already progressed through several layers of selection. Given its secretive nature, it is difficult to say for sure whether or not the NSA has influenced the PQC standards, but there have long been suggestions and rumors that the agency deliberately weakens encryption algorithms. In 2013, The New York Times reported that the agency had a budget of $250 million for the task, and intelligence agency documents leaked by Edward Snowden in the same year contained references to the NSA deliberately placing a backdoor in a cryptography algorithm, although that algorithm was later dropped from official standards.
