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The Cuckoo's Egg

1986

One day in 1986, Clifford Stoll, an astronomer at the Lawrence Berkeley National Laboratory, found that someone was using computer time and not paying for it. Worse, the person was searching for files labeled "nuclear." His investigation led to a West German hacker named Markus Hess who had been selling U.S. secrets to the Soviet KGB. Stoll wrote a best-selling book about the episode called The Cuckoo's Egg: Tracking a Spy Through the Maze of Computer Espionage, published in 1989.

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