Trilight Zone

[tricore]

Computer viruses are one of the most feared Internet threats in the world of today. They have done massive harm and caught a lot of media attention in the recent years. Computer infections come in many shapes and forms, with the most recognized being the dreaded email virus.

There exist four major types of viruses circulating the net. They are the virus, e-mail virus, worms, and Trojan horses.

Viruses are pieces of software that hitch a ride on programs. Whenever the program runs, the Virus runs too, and can wreak havoc or even reproduce.

E-mail viruses are similar to other viruses, except for the fact that when the message a virus rides on is received, the virus usually replicates itself into other e-mail, and sends it to all the people that person has e-mailed before.

Worms are like regular viruses, except that they replicate through the use of security holes. Once a security hole is found, the worm multiplies and continues to infect the system. These are the hardest to prevent and can appear at you in any time. Usually, if a lot of users in your community have been infected with a virus, you may consider obtaining some protection such as a firewall. Worms not only wiggle its way onto your hard drive in total stealth, they usually cause the most damage.



Trojan Horses are computer programs that claim to do something useful, but when run, can allow a hacker to completely possess your computer. The only good news is that the program has no way to multiply automatically. The concept of Trojan horse viruses will be gone over in detail in the separate category.

Computer viruses cannot actually harm you physically, they are programs or chunks of data that contain malicious code which if run cause havoc in a system. They are only called viruses due to their similarities to the familiar biological virus that infects animals and humans. Both “viruses” travel from person to person, or system to system, and will keep spreading unless they are quarantined and terminated.

An interesting thing about computer viruses is, that they require a certain program or system to reproduce. For example, a virus designed to victimize Windows XP users does not affect MAC users nor can it replicate or make copies unless it is the specific operating system version.

The worm is a very interesting form of computer virus. It is a computer program that can copy itself to a computer and continue onwards, to infect even more computers. Once in the machine, the worm spreads out and multiplies, spreading out from the computer across a network connection. Computers without network connections are safe from most worms and other computer viruses, due to the fact that almost all computer viruses are caught when they slip in through a network connection. Once the computer viruses are inside the computer through the network, they look for security holes anywhere they can find them. Most security holes are found in operating software, or in the actual operating system itself.

The computer virus can get into your system in several different ways, and reproduce in just as many different ways. The most common virus, the “Executable” virus, is the type of virus that attaches itself to a popular program, which can usually be attained via the internet. This program then sits in your computer, until it is executed, or opened. The virus then copies itself to the computers memory, along with the program. The virus searches the memory for any other programs to hitch a ride to. If one is found, then the computer virus adds it’s code to the program, thus making it infected. The virus than runs the program on the disk, or the one you downloaded. This way, the unsuspecting user does not know that the virus was ever in his memory. Also, the next time either infected program is run, which can be quite often, the virus looks for another chance to replicate itself. If the program is transferred via a disk or a floppy, or if the program is posted on the Internet for others to download, then the virus spreads. However, the crafty computer virus creators got craftier and improved their viruses. Now, the viruses could load themselves into the memory, and operate as long as the computer stayed running. Thus, the virus could reproduce at it’s leisure while the person operating the system was completely clueless. There is a boot sector on every floppy disk. It is the first thing that the computer loads when the floppy disk is inserted. It tells the system how to load and operate the operating system on the floppy. Thus, if the virus is inserted into the boot sector, then it can guarantee that it gets executed. That way, the virus can load itself into the memory whenever it wants, and start replicating. Nowadays, the executable virus and the boot sector virus are very rare, due to several different factors. One thing is that most programs these days are run on CD s. These disks cannot be altered to allow a virus to hitch a ride on it. Also, most computers now have systems to check and “disinfect” the boot sector of any floppy used.

E-mail viruses are extremely simple, but deadly. Either the virus is contained in a file attachment, or the E-mail message itself contains a malicious Active X control, which if you are using Internet Explorer, can install various components. This is called Malware.

The world gets Slammed!

Effective viruses do not need to have a huge file size. One of these that infected half the globe in 2002 is called “Slammer” for its quick spreading actions and damaging effects. In 9 hours it wiped 5/13 of Internet backbone servers, not only disabling access to the net, but also causing all kinds of damage with utilities services, airlines, and other Internet dependent services. The virus was only 374 bytes and spread through a loophole bug in Microsoft SQL, a server program. This caused $1,000,000,000 dollars of damages.

Macro Virus

You’ve probably heard of a macro as a customization or preset for Microsoft Office. Like many scripting features, it serves the legitimate purpose of advanced document settings and configuration, but the golden rule “with convenience comes abuse” applies to everything.

Before, text files used to be perfectly safe. Now even a word document may make some hesitant to open. That’s because with the scripting, it can permanently damage components and features in Microsoft office. Can it corrupt you documents? Can it affect outside programs?

This can cause an extreme fuss and waste of time as the macro virus tweaks it so the keyboard is reconfigured so letters constantly reappear, your work suddenly gets deleted, and other frustrating effects. Essentially a macro virus can by hidden in any Microsoft Office file whether it be Word, PowerPoint, Access, FrontPage, Publisher and others. It cannot effect outside components but only Office programs, so if you get a virus in PowerPoint as a result of a fake slide show, it has the potential to do the same with PowerPoint and Publisher.

The worst-case scenario is when the macro integrates itself into the office startup task and every time an office application is opened, it corrupts either the document, or important components that enable you to work on it.

The only way to solve this is to uninstall and then reinstall office, which is time consuming and complex task for some.

Fortunately, new security software has come with a macro detecting function so you can have a more pleasant experience.

Viruses are rated as high on the chart of most dangerous security threats.