You've heard the news stories about credit card numbers being stolen
and email viruses spreading. Maybe you've even been a victim yourself.
One of the best defenses is understanding the risks, what some of the
basic terms mean, and what you can do to protect yourself against
What is cyber security?
It seems that everything relies on computers and the Internet now --
communication (email, cellphones), entertainment (digital cable,
mp3s), transportation (car engine systems, airplane navigation),
shopping (online stores, credit cards), medicine (equipment, medical
records), and the list goes on. How much of your daily life relies on
computers? How much of your personal information is stored either on
your own computer or on someone else's system?
Cyber security involves protecting that information by preventing,
detecting, and responding to attacks.
What are the risks?
There are many risks, some more serious than others. Among these
dangers are viruses erasing your entire system, someone breaking into
your system and altering files, someone using your computer to attack
others, or someone stealing your credit card information and making
unauthorized purchases. Unfortunately, there's no 100% guarantee that
even with the best precautions some of these things won't happen to
you, but there are steps you can take to minimize the chances.
What can you do?
The first step in protecting yourself is to recognize the risks and
become familiar with some of the terminology associated with them.
Hacker, attacker, or intruder - These terms are applied to the people
who seek to exploit weaknesses in software and computer systems
for their own gain. Although their intentions are sometimes fairly
benign and motivated solely by curiosity, their actions are
typically in violation of the intended use of the systems they are
exploiting. The results can range from mere mischief (creating a
virus with no intentionally negative impact) to malicious activity
(stealing or altering information).
Malicious code - This category includes code such as viruses,
worms, and Trojan horses. Although some people use these terms
interchangeably, they have unique characteristics.
* Viruses - This type of malicious code requires you to actually do
something before it infects your computer. This action could be
opening an email attachment or going to a particular web page.
* Worms - Worms propagate without user intervention. They typically
start by exploiting a software vulnerability (a flaw that allows
the software's intended security policy to be violated), then once
the victim computer has been infected the worm will attempt to
find and infect other computers. Similar to viruses, worms can
propagate via email, web sites, or network-based software. The
automated self-propagation of worms distinguishes them from
* Trojan horses - A Trojan horse program is software that claims to
be one thing while in fact doing something different behind the
scenes. For example, a program that claims it will speed up your
computer may actually be sending confidential information to a
This series of information security tips will give you more
information about how to recognize and protect yourself from attacks.
Authors: Mindi McDowell, Allen Householder
Produced 2004 by US-CERT, a government organization.
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