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Commercial Quantum Cryptography System Hacked

Posted by Soulskill on from the superposition-of-safe-and-unsafe dept.

KentuckyFC writes "Any proof that quantum cryptography is perfect relies on idealized assumptions that don't always hold true in the real world. One such assumption is related to the types of errors that creep into quantum messages. Alice and Bob always keep a careful eye on the level of errors in their messages because they know that Eve will introduce errors if she intercepts and reads any of the quantum bits in a message. So a high error rate is a sign that the message is being overheard. But it is impossible to get rid of errors entirely, so Alice and Bob have to tolerate a small level of error. This level is well known. Various proofs show that if the quantum bit error rate is less than 20 percent, then the message is secure. However, these proofs assume that the errors are the result of noise from the environment. Now, physicists have come up with an attack based on the realization that Alice also introduces errors when she prepares the required quantum states to send to Bob. This extra noise allows Eve to intercept some of the quantum bits, read them and then send them on, in a way that raises the error rate to only 19.7 percent. In this kind of 'intercept and resend attack,' the error rate stays below the 20 percent threshold and Alice and Bob are none the wiser, happily exchanging keys while Eve listens in unchallenged. The physicists say they have successfully used their hack on a commercial quantum cryptography system from the Geneva-based startup ID Quantique."

2 of 117 comments (clear)

  1. Sure, sure, paint me as the bad one again by Anonymous Coward · · Score: 5, Funny

    Really, is a little fidelity in this relationship too much to ask for? I've caught Bob kissing that skank Alice so many fucking times and he always says he's sorry and he'll stop seeing her, but still I can tell they're exchanging information through hidden channels.

    But what I really hate is when people act like I'm so unreasonable by trying to find out what is going on and who my allegedly significant other is seeing behind my back. What the fuck.

    -
    Cryptographically Signed,

    Eve.

    (Inspired by xkcd, of course.)

  2. Isn't this obvious? by mrsteveman1 · · Score: 5, Funny

    Eve is a fucking spy, arrest her.

    I'm not too sure about Alice and Bob either, seems they're always around when these things happen.