Why quantum computing has the cybersecurity world white-knuckled

As quantum computers inch closer to reality, experts are sweating over their potential to render many of today’s cybersecurity technologies useless. Earlier this year the U.S. National Institute of Standards and Technology issued a call for help on the matter, and this week the Global Risk Institute added its voice to the mix.

Because of quantum computing, there’s a one-in-seven chance that fundamental public-key cryptography tools used today will be broken by 2026, warned Michele Mosca, co-founder of the University of Waterloo’s Institute for Quantum Computing and special advisor on cybersecurity to the Global Risk Institute. By 2031, that chance jumps to 50 percent, Mosca wrote in a report published Monday.

“Although the quantum attacks are not happening yet, critical decisions need to be taken today in order to be able to respond to these threats in the future,” he added.

Such threats stem from the fact that quantum computers work in a fundamentally different way than traditional computers do. In traditional computing, numbers are represented by either 0s or 1s, but quantum computing relies on atomic-scale units called quantum bits, or “qubits,” that can be simultaneously 0 and 1 through a state known as superposition. Far greater performance and efficiency are among the benefits, but there’s also a downside.

“One unintended consequence of quantum computation is breaking some of the cryptographic tools currently underpinning cybersecurity,” Mosca wrote.

Encryption, for example, often relies on the challenge of factoring large numbers, but researchers recently demonstrated what they said is the first five-atom quantum computer capable of cracking such encryption schemes.

“When the cryptographic foundations upon which a cyber system is built are fundamentally broken, unless a failover replacement (which generally takes years to develop) is in place, the system will crumble with no quick fixes,” Mosca wrote. “Right now, our cyber immune system is not ready for the quantum threat. There is a pending lethal attack, and the clock is ticking to design and deploy the cure before the threat is realized.”

In the short term, work needs to be done to design systems that are “cryptographically agile,” Mosca said, and can quickly swap one cryptographic tool for another.

In the longer run, we’ll need “quantum-safe” cryptography tools, he said, including protocols that can run on conventional technologies and resist quantum attacks.

Part of the NIST’s effort will be a competition in which members of the public will devise and test promising new cryptographic methods. Meanwhile, private security firms are working on the problem as well. KryptAll, for example, recently launched an independent effort of its own, with the goal of having a product available by 2021.