'Unbreakable' quantum cryptography hacked without detection using lasers

Posted by Rick C. Hodgin

Oslo (Norway) - A Norwegian University of Science student named Vadim Makarov has discovered a vulnerability in what was previously thought to be unbreakable quantum encryption. He is using a form of high intensity laser light to intercept the encrypted data stream covertly. While quantum encryption is regularly used to secure Swiss bank transactions, as well as their much publicized 2007 election results, Makarov claims it's easily hacked. He claims to have developed a black box device which he says, "turns the equipment into a puppet-box that an eavesdropper can control."

Quantum encryption is a complex process wherein a stream of paired photons are created at the source. Each has a specific and unique quantum signature that can be detected. The sender and receiver both obtain a secret key used to encrypt the message, without which the message is lost. This form of encryption can be used to determine if the message was intercepted en route. It won't tell who intercepted it, only that it was intercepted. And this form of encryption is often relied upon to insure privacy and security. And now it appears it may all be for naught.

According to Makarov, the secret is in the way the sender and receiver communicate their secret key. And it is exactly here where the exploit can be found.

His team demonstrated that it is possible to allow the entire transmission to go from sender to receiver without being altered or an intrusion being detected. The intruder simply hooks into what the receiver is receiving (which is actually very complex). Then, by continuing to monitor the follow-on communications back and forth from sender to receiver wherein the secret key is obtained, the intruder is able to decode the transmission without ever having been detected.

Makarov and his colleagues say they have developed systems that can defeat two out of the three primary forms of quantum encryption used today. And their research is continuing on the third.