a simple essay


Worms and Viruses

Email, though more than decades old, is considered by some to be today’s killer app. Most of today’s business rides on the highways of the internet, as people communicate more by email than by fax and phone. And why not? With email you get a record of conversations and message you send or receive - so for those of us who are a little forgetful, we can look up any email we have stored. It’s quick, fast, and painless communication. Write up a message, press send, and most of the time the email arrives within minutes, that means you’ll likely receive a reply before the end of the hour instead of the end of the day.

However, as many good things as there are about email, it does have its negative side. The problem lies in the conjoined twins of spam and worms. In the past year there has been increasing email traffic of spam, or unsolicited emails. There are current estimates that put the amount of spam anywhere from 33% to 66% of all emails! More than half of all emails could be spam!

In the first issue of First Risk I gave a brief explanation of spam and some hints on how to bring down number of spam that arrives in your inbox. But what about this worm menace? This is something that is very interesting as many people believe that modern virus writers work for spammers (people that send spam). In fact, many worm programs send email addresses gathered from the infected computer to some place on the internet. Many of these worms also have another secret payload that let them send emails from the infected computer. But what are all these things anyways, aren’t they all just a Computer Virus?

People many times attribute problems with their computers to viruses, so any program that does anything bad also tends to be called “virus”. Strictly speaking however, a virus is a piece of programming code only does two things: it executes, and it copies itself. Like the namesake of the code’s real life counterpart, a virus program tries to replicate itself throughout the system it resides. Viruses copy themselves only to certain file types (a virus found in a word document tends to only copy itself into other word documents). Any file that a virus copies itself into becomes “infected” with the virus and will execute the program whenever that file is opened or executed. Whenever they are executed, besides trying to replicate, there are many things a virus can do. There are some benign viruses that only make messages or symbols pop up on the screen, most viruses however, tend to harm other files by deleting or corrupting them.

As bad as viruses can be however, they are becoming less popular throughout the years. It is the strict definition of a virus that is their biggest constriction. Viruses must execute themselves to propagate, and because they propagate only though files they tend to stay within infected systems. This is unlike what has been happening in the past year which has seen programs infecting systems, worming their way through networks. The two biggest attacks this year alone come from two such programs: Sasser and Netsky.

Both of these programs are worms. The main difference between worms and viruses is that worms do not infect files. Worms are self-sufficient programs that copy themselves to different computer systems. Usually only one worm can reside within a computer. While some spread with emails as attachments (that must be executed for the system to be infected), there are some that use security holes in windows and other programs. These new worms don’t need a user to open a program; instead they automatically infect systems that have the security holes open.

After infecting a computer, most worms “set-up shop”; that is to say that they install themselves in the computer, and tell Windows to run them every time Windows starts. Once running, these worms open certain communication ports in your computer to listen for any new instructions, send sensitive and personal information along with email address to certain computer on the internet, and are also capable of sending massive amounts of email. Thanks in part to recent worms Comcast estimates that 33% of its customer’s computers have been infected by worms that constantly send out spam.

These programs are very dangerous to your computer system and private data. Most of these programs, viruses and worms, rely on bugs and security holes inside programs like Outlook and Windows to be able to infect systems. The recent worm Netsky, was able to bypass the Microsoft Outlook XP defense against executable attachments (By default Outlook XP denies access to files with certain extensions) with a link that would make the program run regardless. Even more concerning is that the emails with which these worms send out look like plausible emails sent out by network administrators.

One has to take much caution when a strange unidentifiable email arrives in their inbox. Besides exercising caution, there are several pieces of software that are invaluable in helping you be protected against spam, worms and viruses. Always run only one Anti-virus program. Besides slowing down your system, anti-virus programs don’t play nice and may raise false alarms; I recommend Norton Antivirus. Install a firewall. Firewalls protect your computer from network attacks both from your computer and from outside. Most firewalls ask you when programs access the internet, here you can allow or deny access to only certain programs; I recommend Norton Internet Firewall, or the free Zone Alarm.

Spyware and Adware

Unsolicited email is not the only way to infect your computer with evasive and untrustworthy programs. Many commercial applications sometimes are bundled with other applications that spy on your computer habits or simply display ads. These applications are known as spyware and adware respectively.
computer attack

Adware, while not intrinsically terrible, is usually found in free and reduced packages of commercial software. It allows the developer to release a version for free, but still receive payment. It may seem like a decent compromise to use a product for free, but the fact is that most adware companies use dishonest tactics and policies. Once installed, adware products cannot be removed, even after removal of the accompanied software. Adware programs are also very similar to spyware programs as they tract your web traffic to show you targeted advertisements.

Spyware programs, go further into what they tract about your habits and information. Such programs can record personal as well as sensitive information such as credit card numbers, and passwords. This information is stored on your computer before being sent to a computer on the internet. You can unintentionally download a spyware program by innocently “surfing” on the Internet and clicking yes on a pop-up dialog.

There are dedicated programs, like Ad-aware, that find and remove both adware and spyware programs.


Phishing is a type of email scam that’s a very popular way of trying to “fish” for identity information. Usually you receive and email that is very important from a commercial site you may do business with, like PayPal, eBay, or Amazon.com. The messages claim that your data has been lost, or that they want you to update your information. A link in the message takes you to page that looks like the organization and shows a form for you to put all your personal information and password, including credit card and social security numbers. However, this page is not from the organization it claims to be, and the information you give it is used for identity theft.

Be very careful with the information you give out on the internet. Read the policies of all websites that you do business with. If you receive an email that claims to be from an organization that isn’t a response to a query initiated by you, be wary; most companies like eBay and amazon.com will not send you any messages that pertain to your account unless it was as a response by an action you started - like buying something on the website.

Always practice carefulness when confronted with anything unexpected in your computer, email, or the internet. If you’re surprised by what you see proceed cautiously, every one of these programs and scams discussed in this article try to get themselves into the door by startling you.

About Computers


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