UNDERGROUND

‘like a shipwrecked man washed ashore on a Tahitian island populated by 11 000 virgins, just ripe for the picking’.

They found a YP, or yellow pages, database linked to 400 of the computer sites. These 400 sites were dependent on this YP database for their password files. Mendax managed to get root on the YP database, which gave him instant control over 400 computer systems. Groovy.

One system was home to a senior NorTel computer security administrator and Mendax promptly headed off to check out his mailbox. The contents made him laugh.

A letter from the Australian office said that Australia’s Telecom wanted access to CORWAN, NorTel’s corporate wide area network. Access would involve linking CORWAN and a small Telecom network. This seemed reasonable enough since Telecom did business with NorTel and staff were communi- cating all the time.

The Canadian security admin had written back turning down the request because there were too many hackers in the Telecom network.

Too many hackers in Telecom? Now that was funny. Here was a hacker reading the sensitive mail of NorTel’s computer security expert who reckoned Telecom’s network was too exposed. In fact, Mendax had penetrated Telecom’s systems from NorTel’s CORWAN, not the other way round.

Perhaps to prove the point, Mendax decided to crack passwords to the NorTel system. He collected 1003 password files from the NorTel sites, pulled up his password cracking program, THC, and started hunting around the network for some spare computers to do the job for him. He located a col- lection of 40 Sun computers, probably housed in Canada, and set up his program on them.

THC ran very fast on those Sun4s. The program used a 60 000 word dictionary borrowed from someone in the US army who had done a thesis on cryptography and password cracking. It also relied on ‘a particularly nice fast-crypt algorithm’ being developed by a Queensland academic, Eric Young. The THC