Stalking the Wily Hacker

Published in Communications of the ACM in May 1988, this article documents Clifford Stoll's investigation into a persistent computer intruder who attacked the Lawrence Berkeley Laboratory in August 1986.

Rather than simply blocking the intruder, Stoll and his team allowed the hacker access while monitoring and tracing his activities back to their source.

The article details the intruder's sophisticated techniques, including exploiting security holes in operating systems, creating hidden accounts with system privileges, and using Trojan horses to capture passwords.