Markus Hess

Markus Hess is a German hacker from Hannover. From 1986 he used dial-up and X.25 connections to reach Lawrence Berkeley National Laboratory in California and, from there, to attack roughly 400 U.S. military computers, including systems at the Pentagon, MITRE, and military bases in the U.S., Germany, and Japan.

The Cuckoo's Egg

A 75-cent accounting discrepancy led LBL system administrator Clifford Stoll to notice the intruder. Over ten months Stoll logged Hess's sessions with printers, built a honeypot of fake SDI documents, and worked with telephone companies and the FBI to trace the connection to Hannover. Hess was arrested in June 1987.

Trial

The investigation revealed that Hess had sold material to the KGB alongside Karl Koch and others. In 1990 he was convicted of espionage and given a suspended sentence of one year and eight months.

Timeline

• 1986-08Clifford Stoll notices a 75-cent accounting error at LBL that leads to Hess's sessions.
• 1987-06Arrested in Hannover after the trace from LBL.
• 1989Clifford Stoll publishes 'The Cuckoo's Egg' about the investigation.
• 1990-02Convicted of espionage in Celle and given a suspended sentence.