Virus Attacks Why do people write and spread viruses? because they think they can they want to prove they can "bring down the big boys" (usually Microsoft is a target) to "prove" how vulnerable we are and in some oddball way, get our attention some people are just destructive and have too much time on their hands to become somewhat of a celebrity amid that "virus-creating community" What is a virus? A virus is a file that can infect other files in a computer or a network and can produce undesired side-effects. These effects can range from harmless messages, data and file corruption, and even some hardware destruction. Some viruses can rearrange the data on your hard disk, destroy the FAT (File Allocation Table), and the disk directories. They can also cause  minor effects such as displaying on-screen messages or graphics, deleting or destroying data, or cause problems with usual computer funtions including printing. Do viruses have relatives? Related to viruses and sometimes called that, are Trojan Horses and Worms. Trojan horses enter your computer via an innocent looking program which then installs itself and causes file damage or security compromises. Unlike the virus, it does not try to reproduce itself. A Worm is a self-propagating virus. The worm disguises itself as an email attachment. This attached file is the actual worm code, and it propagates by locating valid email addresses. The worm modifies files like wsock32.dll and attaches itself to computer operations, beginning the worm's work. When someone posts an e-mail message to another user or to a news server, the worm sends a copy of its e-mail message with an attachment of its code. These types of chain letter worms are very successful because people usually trust messages they receive from friends and associates. Can viruses damage hardware? The urban legend we hear about "viruses destroying your hard drive" is an exaggeration but viruses can cause damage so we can't get to the all-important sectors of our hard drive. Virus attacks changed intensity in 1998 when the Win95/CIH became the first virus to damage system hardware, specifically the flash BIOS, a file that operates your computer's  input/output system. CIH, like Win95/Anxiety, implements an infection mechanism based on VxD. Virus writers have written several Win32 viruses that attack kernel32.dll, which effects how your computer loads applications.   What are the classification-types of viruses? File Infecting-seems to be the most common and infects files with .EXE or .COM extensions. Rarely do the files get destroyed because the virus uses these files as vehicles to carry itself to other files, which become infected. Master Boot Infectors-the first physical sector of every hard disk (Side 0, Track 0, Sector 1) contains the disk's Master Boot Record and Partition Table. The MBR has a small program within it called the Master Boot Program which looks up the values and tells the system to go there and execute any code it finds. When the boot sector program is read and executed, the virus goes into your computer's memory and infects the MBR of your hard drive. This type is written in assembly language Boot Sector or System infectors-places itself in the part of your computer used to boot. It replaces the original boot program with itself and will begin to infect on startup or boot. The virus will place itself in memory and the infect any disks it comes in contact with. This is also assembly language. Macro Viruses-up to now, only programs can contain viruses. While not impossible, pictures and images are less worry. Microsoft programs are common target of virus attacks, with the most common being MS Office programs. These contain macro language, small programs that help you do complicated tasks and are usually stored in template files. The common macro language is Visual Basic and documents like Excel spreadsheets, Microsoft Word word processing documents, and Access databases, include programming language that can be infected.  Multi-partite viruses-are some of the deadliest because they can attack both sectors and executable files.  Worms-are types of viruses in that they make copies of themselves, but differ in that they need not attach to particular files or sectors at all. When the  worm is executed, it looks for other systems-rather than parts of systems-to infect, then copies its code to them.  Are there Virus Hoaxes? There are many reported virus attacks that can be read about in e-mailings etc., that are hoaxes. That topic is addressed at a web site called Vmyths and is worth the time to check.  You can also check this page from Symantec to check on hoaxes. Anti Virus Tools- There are many types of tools that will protect against viruses. Here is a preview. For details, navigate to the specific pages. An anti-virus tool is worthless unless you continually update!!! Many will install a program and never update it, making it completely inept at finding the latest viruses. Don't have a false sense of security just because you have an anti-virus program on your computer. Most companies allow upgrades as part of their service. Online scanners can find and sometimes fix the virus and are often free of charge. These do not keep the virus from getting into you computer.  Anti-virus programs or sometimes called "scanners," will load onto your system and monitor to alert you if a virus is trying to get in. This is much better than an online scanner because it will attempt to keep the virus out of your system. Firewalls can also be used to keep unwanted probes and viruses off your machine Virus Specifics- While there are a handful of the most common viruses that stick around and surface from time to time, a more complete list can be found at several places. This is more technical than some like to get but specific information can be found at: About.com's site---includes a database of info, current news of threats and hoaxes, and suggestions on fixes. Trend-Micro's Virus Info Center---covers the latest and most common viruses with plenty of info. It also includes a free scanner option where you can have them scan your hard driver (it's safe), detect any viruses, and clean them. F-Secure Virus Description Page---where you can find an extensive database of viruses dating back to 1994. Complete with any info you can find useful and then some F-Secure.com's Wildlist---where you can find technical descriptions of viruses F-Secure Virus Pictures---where you can bring up a virus and see a particular or specific graphic that it will put on your screen. Trend-Micro Top 10---will show you the 10 top viruses in the world at any given time, show details, and give suggestions for cleaning. In fact, if you run your pointer-arrow over the detailed map, you can see what the Top 10 is for any continent. Truly a world-wide site. Command Software's Virus Info---gives a complete "encyclopedia" of viruses along with daily updates on new virus attacks and hoaxes. Computer Associates Glossary---gives a comprehensive list of terms in a glossary. Computer Associates Virus FAQ---a fairly complete list of questions and answers Computer Assoicates Virus Incidents---discusses what to do if you think you are a victim of a virus, a hoax, or a false alarm. USENET Virus Newsgroup---alt.comp.virus newsgroup. By using your newsreader, you can keep up to date with a bulletin board of Q's and A's from some of the most informed users on the internet. Some of the better known companies and software anit-virus products- An excellent listing can be found on the Claymania site where many from the list below will be detailed. It's worth a look as well as a "comeback" in that the industry of virus protection is ever-changing as is the Claymania page. Another list is below (I have not given individual links for these companies-they change often but you can do a search through Yahoo or Google to find the current sites).    Antivir   Avast   AVX    Command Antivirus   Dr. Web   eSafe   F-Prot for DOS, F-Prot for Windows   F-Secure   Gecad   Grisoft AVG   InoculateIT  CA InoculateIT Personal Edition  CA InoculateIT Corporate Edition   Kaspersky Antivirus (KAV)   McAfee VirusScan   NOD32   Norman Virus Control   Norton Antivirus   Panda Antivirus   PC-Cillin   Sophos Antivirus   Computer Associates Vet Anti-virus  Proland Protector Plus   QuickHeal  REMEMBER- whatever the company or program, it will be worthless without regular updates-perhaps weekly!! The most common of the viruses updated monthly can be found on the home page of this web site.