Attacks and Counterattacks

Hackers have a variety of motives, and their ploys tend to reflect that fact. Some regard network
intrusion as a harmless sport and do little or no damage after they have achieved access. Others
regard sabotage itself as a sport and intrude in order to destroy. Others engage in industrial
espionage, seeking to steal information and sell it for a profit. Still others are hired assassins
seeking to wreck a network at the behest of a competitor. Yet another group intrudes primarily
to steal software for redistribution. And a surprisingly large number of hackers seek to enter a
network to use it as a launching platform for further attacks, thus disguising the ultimate point
of origin of such attacks.
In the case of public networks, hackers may attempt entry not to attack or compromise the
access network itself but to breech an enterprise network attached to the public network. Or
they may want to eavesdrop on private transmissions either out of voyeuristic motivations or
for financial gain.
The arsenal of tools used by experienced hackers today is enormous, much too large to be
discussed in this chapter. Unfortunately, such tools are readily available as freeware at hacker
Web sites, of which there are hundreds if not thousands. And the ready availability of such tools has had extremely unfortunate consequences. In the 1970s and 1980s, hackers tended to be
young computer professionals, and because the knowledge base required at the time was so
extensive, not too many of them existed. Today any computer-savvy adolescents with a yen
to hack can easily equip themselves with the weapons to do so without understanding the
mechanisms by which they operate. We are also seeing an increase in the activity of cybercriminal
gangs who commit computer crimes for profit. Many of these organizations operate
in Eastern Europe.
Fortunately, security software has kept pace with the democratization of hacking, and the
security professional now has a large arsenal available. And while the number of products on
the market is considerable, the basic approaches they embody are not numerous, and the network
operator should be able to easily comprehend them.