One of the four post-quantum computing encryption algorithm standards selected by the US National Institute of Standards and Technology (NIST) for public key encryption is open to side-channel attacks, researchers warn.

A new paper published by a team from the Royal Institute of Technology in Sweden reported that Crystal-Kyber implementations under certain masked implementation conditions could be vulnerable.

"Crystals-Kyber has been selected by the NIST as a public-key encryption and key encapsulation mechanism to be standardized," the paper's abstract explained. "It is also included in the NSA's suite of cryptographic algorithms recommended for national security systems. This makes it important to evaluate the resistance of Crystals-Kyber's implementations to side-channel attacks."