A quantum crack that wasn't: new attack hits photon detector
Quantum cryptography has gained a lot of notoriety in recent years because it is thought to be fundamentally secure, relying on the laws of nature to guarantee security. The basic idea boils down to the fact that no one can observe a quantum system without altering it. The alterations can be detected as an increase in the error rate of the communications system, alerting everyone to a potential eavesdropper. A recent conference publication has highlighted a weakness in quantum cryptography systems, but it focuses on the classical (e.g., not quantum) part of the communications system, which can be used to fool the key distribution system into giving up the secret key.
