📸

investigating a 75 cent discrepancy in the accounting records for the lab’s computers. (The 75 cent fee couldn’t be attributed to an authorized user, so the charge had to have been run up by an outsider.) Other system operators might not have bothered, but Stoll was an astronomer by vocation and was only filling in time until grant money could be found to allow him to pursue his chosen career. To Stoll, chasing a hacker seemed exciting, not time-wasting.

Once he had detected Hess, he was faced with the classic dilemma: should he lock him out or watch him? If he were to lock him out, there was a chance that he might sneak in some other way and not be noticed; it was also likely that he might penetrate some other system. Stoll decided to keep a watch, setting up an intricate alarm system that would tip him off whenever the hacker appeared. He even slept at the lab on occasions. His principal intruder was Hess, whom he knew only through his various aliases — but he did also note the presence of both Pengo and Hagbard (Koch) on other occasions. These two, with their interest in the VAXen that used VMS, were not a major source of worry for Stoll on his UNIX site.

It eventually became obvious that Lawrence Berkeley had nothing to interest the hacker; it was just a convenient jumping off place. Stoll tried to make things look a bit more exciting and concocted a 'secret' file as bait. It was a pure fiction, but the hacker gobbled it up.

Stoll subsequently recounted his experiences in an academic paper ('Stalking the Wily Hacker', 1988) and a best-selling book, The Cuckoo's Egg (1989). He would record the heavy artillery that was eventually wheeled out to deal with his German hackers: the FBI, the CIA and, the super-spooks themselves, the National Security Agency.

The reaction of the various agencies at first ranged from apathy to annoyance. Stoll was hard pressed to interest the authorities at all: losses in hacking incidents are generally estimated in nice large numbers, and chasing 75 cents seemed like a joke. But he persisted, and eventually the authorities became nervous about hackers roaming around systems devoted to military research and mounted an operation to catch the Berkeley intruder. Finding him was a matter of tracing his calls back to their source. But the calls were routed through

📸