ViruS ComPuTeR

Plagued by Boot Infectors?

Has your computer been dragging as of late? All of a sudden you can't access certain files or programs - your system keeps crashing. If so, you just may have a malicious program controlling the system from the internal sectors of your computer - you just may have contracted a boot infector, a virus that has compromised thousands of computers.

Boot infectors go by many different aliases: boot sector infectors, boot record infectors, boot viruses and system viruses. Regardless of the name, they are rather common and can be very destructive. A boot infector attacks the critical section of a floppy disk or hard drive that helps to start your computer. When the computer starts up, the malicious code is launched by the system and your machine becomes wide open to virus coders. The deployment of the infection gives them sort of a guarantee for future attacks. With enough skill, an intruder can obtain complete control over your system and take what ever actions they desire.

Like all viruses, a boot infector functions with the intend of spreading the infection throughout the host system. It usually copies itself to a sector and creates bad sectors along with it's malicious code. It then attempts to execute itself when the computer is booted and claim control as the system continues to run. Some are able to trap other types of boot request such as "CTRL, ATL, DEL", allowing the virus to remain in control even when the system is booted by a non-infective floppy disk. This results in the clean copy becoming instantly infected.

The Pakistani Brain virus is one of the most popular boot infectors This infection has been upgraded in a way that enables it to easily infect hard disks, completely destroy FAT entries, numerous files, and terribly slow down the performance of a computer.

Effects on Windows

Microsoft Windows is known for being more vulnerable to computer viruses and other exploits. In fact, many of the infections commonly used today were specifically coded for Windows platforms. In many instances, a file infector such as a resident virus can prevent an older DOS system from starting at all. When this occurs, the victim will typically have knowledge of the problem. From there they can make an attempt with virus removal software, though taking the machine to a technician would probably be the best move.

However, a Windows system that contracts a boot infector will behave quite differently and is susceptible to great damage. With a boot virus, the operating system will not only start, but spread the infection from within Windows. Because of subtle movement, it may be a good while before a user learns they have contracted a boot infection. The computer will often start up without flaw and function as expected for sometime. Eventually, the virus will distribute itself to numerous sectors and slowly begin a wave of infection. Without a reliable anti-virus program, the victim will typically have no knowledge of the infection and see no need to get rid of it.

Protecting against File Infectors

By merely surfing the internet, you are exposing yourself to a wide range of security threats. Some of the most common dangers are computer viruses. Many types of viruses may attempt to slither into your computer and spread an infection throughout the system. And while several are similar in function, most have notable distinctions that set them apart.

Categories of File Infectors

According to Symantec, one the leading developers of anti-virus software, all viruses fall under five major categories:

- MBR (Master Boot Record) viruses

- Macro viruses

- Multi-part viruses

- Boot sector viruses

- File infector viruses

As the name indicates, the role of a file infector is to infect the files of a computer. This is one of the most frequently deployed viruses and has been known to inflict considerable damage. Upon running a program that has been corrupted by a file infector, the virus duplicates the malicious code and applies it to other executable applications on the computer. Files that are the most vulnerable to this type of infection bare the extensions of EXE. ( execute) and .COM (command), though any file capable of execution can be infected.

A popular example of the file infector is the Cascade virus, an infection that has basically become obsolete. The original variation of this virus was designed to deliver a payload from October 1^st through December 31^st in 1988. Upon execution, the characters on the victim's monitor descend and find themselves piled at the bottom of the screen. The Cascade virus has spawned a number of variants over the years, most of which have displayed the same basic function.

A more recent example of a file infector is the Cleevix virus, which is reported as being first discovered in January of 2006. When executed, it seeks out the current directory, the system directory and the Windows directory. It then infects all portable executable files within them. Because the infection typically displays a message upon execution, it is fairly easy to detect. Other than being equipped with a few encryption features, Cleevix as a rather simple virus that can be removed with ease.

Characteristics of File Infectors

Although there are many different kinds of file infector viruses, most of them operate the same and take the following course of actions.

- Once a user executes an infected file, the virus copies the file and places into an area where it can be executed. In most cases, this would be the RAM.

- The malicious code runs first while the infected file remains quiescent

- The virus then copies itself in a location separate from where the infection occurred, allowing it to continuously infect files as the user functions other programs

- When the initial process is set in to place, the virus grants control back to the infected file

- When a user opens another application, the dormant virus proceeds to run again. It then inserts a copy of itself into files that were previously uninfected which enables the cycle to repeat consistently

File infectors can be both a nuisance, as well as a tremendous threat to your computer. For this reason, it is recommended to protect your system with anti-virus software that receives free updates for the latest virus definitions.

Understanding Program Infectors

There is a lot of infection malware circulating throughout the internet, all of which can easily find its way to you. The internet has become an open platform for malicious individuals distributing spam emails carrying scams, self replicating network worms and Trojans capable of launching intrusive spyware. All of these harmful programs are often associated with a virus, one of the greatest threats posed to your computer.

With all of the nasty infections cluttering cyberspace, it is important to build a virtual fortress around your computer to keep the intruders away. A great place to start is learning more about the most common viruses and how they function.

Viruses are classified in many different ways and have spawned several variants. Three major types include boot infectors, system infectors and general program infectors. Boot infectors are typically installed into the boot sector of a floppy disk or hard drive. Popular examples of this infection are the Alameda virus and the Pakistani Brain Virus. System infectors spread by attaching to a device driver or module of the operating system. An example would be the Lehigh virus which uses components from another host to infect areas of an operating system.

Program infectors make up the largest classification of viruses. It has the ability to attach itself to any kind of application software, taking complete control when the infected program is run. From there, it roams the system in search of other host programs, whether they're on the hard drive or a floppy disk. After finding victims, the infection spreads further, giving control back to the original program. It many instances, a user may have no indication of a virus as programs may function normally for sometime. Over time, the applications will endure complication or corrupt the system due to multiple infections.

Considering the numerous variations, program infectors stand to cause major problems for home computer users and large networks alike. These viruses replicate themselves at a fast rate, claiming loads of memory and bogging down your machine. One of the biggest concerns involves having all of your important files overwritten and replaced with malicious codes. This could be data pertaining to online confirmations, purchase details or payroll information. Losing these files to a virus could spell disaster for several people. Program infectors can completely shut down your favorite applications and render your devices useless.

Methods of Prevention

With the prevalence of malicious viruses we endure in the internet-era, many users have taken extreme measures to prevent these threats from attacking their systems. Here are a few tips to keep you safe program infectors and several other viruses:

- make backup copies of all data files and programs on a regular basis

- use extreme caution when downloading public-domain software and always scan the program for viruses

- always boot an operating system from a write-protected disk

- remain aware of unusual activity in regard to programs or the system itself

Trusted Security Software

In addition to the basic security procedures, you can keep the viruses at bay with a number anti-virus programs. These solutions are widely available and can be installed on your system in minutes and start protecting you right away.

Protecting against the FAT Virus

The FAT, short for File Allocation Table, is a mechanism employed by Microsoft and used in most Windows operating systems. It's job is to keep track of all the contents on a disk. The FAT is basically a chart which contains numbers that correspond to cluster addresses on a hard drive.

FAT12, the oldest version of the File Allocation Table, uses a 12-bit binary system. This type of system is no longer used to format a hard drive as the maximum volume size was quite limited. If a computer running Windows 95 or higher displays the File Allocation Table as FAT12, it is likely that the hard drive is terribly corrupted and may be infected with a virus.

A FAT virus can be rather dangerous as it infects a vital part of the computer's operational process. It has the ability to prevent access to certain sections on the hard drive where important files are located. As the virus spreads it's infection, these files or even entire directories can be overwritten and permanently lost.

The Link Virus

Computer viruses are generally classified in accordance to what they infect, and the way they spread infection. A common threat to the File Allocation Table is the link virus. Instead of inserting a malicious code directly into infected files, it distributes itself by manipulating the method in which files are accessed by the FAT file system. Once an infected file is executed, a link virus typically slithers into resident memory and writes a hidden file to the disk. Subsequently, it alters the FAT in a way that cross-links other files to a sector of the disk that contains the viral code. As a result, the operating system jumps to the original code and launches it whenever an infected file is run, granting complete control to the virus.

How Linking Works

The technique of cross-linking can be detected when a CHKDSK program is run, though a FAT virus could employ a stealth mode to conceal changes when it resides in the memory.

Some of these viruses do not rely on executable files to infect the FAT. Instead they copy themselves to a wide range of folders and wait to be launched by the user. Many virus writers give their infections names such WINSTART.BAT or INSTALL.EXE to persuade a user into launching a file that contains the malicious code.

An FAT virus will not modify host files. It can, however, force the operating system to execute the viral code altering specific fields in the FAT file system, which can be just as damaging.

Link viruses and other infections that attack the File Allocation Table of a computer are complex and often difficult to identify. Most of the time, a user will have no knowledge of its presence as the virus gradually corrupts the computer.

If you happen to experience performance issues that indicate an FAT virus, you can refer to the map of your hard drive to learn what files should actually be in the system. If viruses are identified, you can simply place them in the recycle bin yourself.

Military Viruses

Viruses can wreak havoc on any computer and they are most likely to strike computers which are connected to the internet. No computer is safe and this means that all computer users need to spend a large amount of their time securing their computer against these viruses.

Virus

Viruses are particularly nasty pieces of software which are written for malicious purposes. Some viruses are pretty harmless but others will cause your PC a serious amount of harm. Many of these will also compromise the security of your computer which will make it easier for hackers to steal your identity.

Corporate Viruses

It's not just individuals that suffer from viruses. Large businesses also still find themselves affected by these horrible programs. Corporate viruses are on the rise thanks to networks and a worm is able to easily spread throughout the entire network without any intervention.

As everyone is connected to the internet the spread of viruses and worms is made very easy. It's possible for these viruses to spread throughout the world in days compared to the months it use to take before the popularity of the internet.

Military Viruses

Even the military is at risk of computer viruses. Obviously they will take the threat of viruses much more seriously than most computer users. Military computers are privileged with lots of top secret and sensitive information.

Many of these computers also have the ability to control weapons. Needless to say it's vital that security of these computers isn't compromised. The military must be very careful with their data and will do everything they can to secure their network.

Even so, there have been a number of examples of viruses hitting military computers. The military won't own up to all of them but most of the rumors are certainly true.

One of the most revealing is the naked wife virus. This spreads by sending emails to contacts telling them that they have a picture of their naked wife. People are so intrigued that they open the email and try to view the picture.

This just goes to show that a computer is only as secure and honest as the person using it. If someone can be tricked into opening a file then it's very easy for a file to be installed, even if it is on military computers.

Protecting Computers

To protect your computer you don't need to use the same systems as the military. Instead you can use a reliable antivirus scanner, firewall and security suite. These utilities can be run regularly to ensure you are fully protected. The firewall will also help you avoid any future problems by blocking access to your computer for hackers.

Guarding against Network Virus

While the primary intent of anti-virus software is to prevent worms and viruses from infiltrating an organization's network, some programs fail to detect more complex infections, thus enabling an outbreak to start. This issue primarily arouse from the widespread use of laptop computers and mobile computing in general. Since many users tend to operate mobile devices with no security implementation at all, an entire network becomes susceptible to infection. Once a virus establishes a strong hold within the network, removal often becomes difficult for the most advanced anti-virus software. Additionally, intrusion detection systems and firewall components have a difficult time preventing the network virus from propagating to other files and devices.

A network worm or virus has the ability quickly degrade the performance of a network, totally disabling critical devices, programs and network connections. Once the infection spreads, fully eradicating it often becomes difficult. Reinfection typically occurs which prompts a spiraling support effort and inflating cost when attempting to recover from the initial outbreak.

The Answer

The best solution for defending an interconnected organization is to implement a program equipped with a network-based firewall. This type of software can be configured to automatically repair infected network devices and more importantly, prevent the virus from occurring.

A network-based firewall uses a combination of techniques to detect, contain and eliminate viruses known to plague a network. Here are some of the common features you'll find:

Outbreak Monitoring - Keeps track of changes in traffic flow, connections made to and from a particular client and sudden increased traffic through ports and protocols such as TCP, UDP, IGMP, and ICMP. The system administrator is immediately notified of any infectious host computers that are detected.

Outbreak Prevention - Prevents the spread of viruses over WANs (wide area networks) by using file, IP address, port and protocol filtering. These processes may be automated or configured manually to give the user greater flexibility and control.

Scanning and Detection - This type of program uses virus scanning technology to detect the latest network threats, dropping the infected packets before they have a chance to be executed.

Security Enforcement - The enforcement of strict security polices greatly reduces the threat of worms, viruses and other infections, setting guidelines that ensure the protection of a network. Some of the actions it may enforce typically include the detection of other anti-virus software that create conflict or automatically downloading virus definitions and scanning technology from an online database. It will also check for compliance of these policies among authorized users who access the network. Those found not to be in compliance can then be directed to comprehensive instructions that detail how the application is to be updated and receive training on any other areas that correspond to the network's security policies.

Where to Find Them

Network-based firewalls have been implemented by a number of security vendors. Some examples include Symantec's Endpoint Security, Norton's 360 and TrendMicro's Virus Firewall. When the integrity of your organization is on the line, it's important to protect it with the best security available.

Self-Defense: Virus Protection

If you frequently surf the internet, you are sure to be encountered by a computer virus at one time or another. It may be introduced via email, within a program you attempt to download, or a website you visit. The best defense against a virus begins with awareness and ends with prevention. The purpose of this article is to educate you more about these nasty infections and a few ways they can be easily avoided.

The Truth about Viruses

Most internet threats including viruses, worms and Trojans spread themselves via email. A good way to keep these infections away from your computer is to keep your preferred email application current with updates. Contrary to popular belief, you CANNOT be infected by a virus just by opening or reading an email message. The hoax claiming that infections spread by opening an email with a virus-indicating subject field is not true. This misconception has been going around for years and has struck fear in many users. To put it in more simple terms, a virus cannot free itself from your inbox and infect your computer.

In order for a computer virus to be effective, some type of explicit action is required on the user's part. What makes this possible is the fact that many emails contain attachments. An attachment may be a word document, or an audio or video file. An attachment may also be a virus in disguise. By opening the attachment sent with an unsolicited email, you're taking a great risk. When that document is downloaded to your computer and opened, the payload of that virus is unleashed and immediately looks for ways to spread the infection.

Protecting Yourself

Keeping email-born viruses from your system is fairly easy. Since there is no standard method of distinguishing genuine attachments from infected ones, the best advice is to never open those sent in an unsolicited message. Regardless of how tempting it seems, knowing that your computer and everything on it could be at risk should be enough incentive to fight temptation. Caution should be practiced even if the attachment is sent from a friend or known source. Email viruses such as ILOVEYOU and Melissa infect a user's address book and propagates itself in the victim's name. In this instance, you may want to give the sender a call to make sure the email and it's contents are safe.

Software is the recommended solution for keeping viruses away from your system and eradicating them as well. Reliable products from McAfee, Symantec, Kapersky and many other vendors have established reputations for creating some of the best anti-virus software. These programs include sophisticated scanners that will run a quick and thorough search of your entire system, capable of detecting an array of malicious content from viruses to spyware.

Viruses pose a great problem to the modern computing environment. At the same time, exposure to these common threats isn't something you have to deal with. Your chances of contracting a virus can be greatly reduced by taking a few basic security precautions and locking your computer down with quality software.

How to Avoid Computer Worms

From updating your security software to being aware of the emails in your inbox, there are many steps you can take to protect yourself and your computer from worms and viruses. One of the most important and simplest ways to protect yourself from computer worms is by being careful and aware of what kind of emails and attachments you receive, what you open and whom it is from. There is a lot of junk and spam email with viruses and worms that ends up directly in your inbox. So, you have to be careful who sends them to you and think twice before opening them.

If you are not expecting an email or do not recognize the person, then the best idea would be to delete it right away and forget about it. If you realize later that you do know the person, do not panic. Chances are they will write back to you again. Also, be aware of attachments and emails you receive from your own family and friends. Most of the time, people receive viruses and worms from individuals they know. Your friends may not realize that they are sending you a virus. So, your job is to inform them and fix the problem before it causes more damage.

Another step you can take to protect your computer is to regularly update your anti-virus software . Make sure that you are using the most up-to-date and enhanced version of your software, so it can catch all those new viruses and worms out there. Also, make sure to check if your software is installed correctly. Sometimes, people do not install the software properly and realize this only when their computer is attacked with a virus or worm. If you don't know how to install the software, have some who knows how to, to install it for you. Also, have him or her explain the steps and procedures to you so next time you need to update or install your software, you can do it yourself.

Finally, when you use email programs, use the ones that have built in spam filters , for instance, Outlook Express, Windows Hotmail and so on. This way, not only will the email be tracked and filtered for viruses, but you will also feel secure that your computer is free from worms and viruses.

In 2003, more than 10 million Americans fell victim to identity theft.

Identity theft costs business and individuals $53 billion dollars annually

In 2003, Americans spent 300 million hours resolving issues related to identity theft.

70% of all identity theft cases are perpetrated by a co-worker or employee of an affiliated business.

What Online Virus Scan is Good for Your Computer?

Aside from the numerous financial scams and attempts at identity theft, viruses are the biggest threat to anyone surfing the internet. These programs are unique and often malicious in nature, capable of inflicting irreversible damage to your system. Virus writers have become so advanced that an infection can be installed and executed without your knowledge. This is why you should be equipped with the tools needed to learn if your system has been corrupted. If there is no anti-virus software protecting your computer, there are many freely available online virus scans that may be utilized.

Choosing the Right Online Scanner

When looking to perform an online scan, it is very critical to first learn a bit more about the site itself. You would be surprised at the large number of individuals abusing the anti-virus industry. These people prey off fears of the consumer, luring them into using malicious scanners that download viruses, spyware and more. It is very wise to only visit sites that are well known for their services and have a solid reputation to back it up. Perform an online search and find out what prominent software reviewers and users are saying about them.

After finding a trusted website, you need to devout special time to perform the scan. This should be at a time when other programs are not functioning. The internet connection typically causes both processes to interfere with each other, slowing down the scan and what ever program you're using. The best advice here is to let the scan work it's magic before attempting to use the computer.

You may also encounter a few sites that carry ulterior motives behind their free service. In this scenario, the virus scanner is free to use at your leisure, yet a fee is required to eliminate any detected threats. This can be rather unsettling if you actually do have a virus ailing your computer. When placed in this unfortunate situation, you generally have two options: buckle down and buy the service to cure your system, or invest in your own anti-virus solution.

Other Options

Many Internet Providers and computer distributors provide their clients with quality anti-virus software with the purchase of new service. The contract is usually for a one-year subscription, from in which you must reactivate when the time expires. This is a good option that will save you a few dollars in the beginning while keeping your computer safe for the time being.

Implementing your own security system isn't a bad idea either. In most cases, this is the best option. Many of the more known products come included with free updates, keeping you current with the latest virus definitions. More of them have also become compatible with other types of scanners that specialize in detecting spyware or malware in general.

These days, protecting a computer from the threat of viruses should be a priority for all of us. Whether it's a free scanner, an online utility or a deluxe internet security suite, you should invest in one right away and put it to action as soon as possible.

How to Prevent Macro Viruses

To find out how to eliminate macro viruses, lets take a quick look at what are macros. Macros are found in computer systems. Macros store a series of commands or actions, allowing the automation of the tasks that you usually complete while using computer applications. Many applications, such as Microsoft Word and Excel, support macro languages. A macro virus attacks these kinds of applications, infecting the documents and template files. So if your computer has a macro virus, and you use a word template file to make a new document, it'll also become infected by the virus. One of the common ways, a macros virus can harm your computer is by replacing the normal functioning macros, and causing a series of automatic actions that prove destructive to your files. Some examples of macro viruses include: Melissa macro virus, Word macro virus, Office XP macro virus, and Apple macro virus.

Does My Computer Have a Macro Virus?

A macro virus can transfer to other computers and applications through various ways, such as, by opening email attachments, downloading applications, sharing infected floppy discs, and through networks and modems. Since, the macro virus is a fairly new type of computer virus, it may slip by your antivirus software .

Therefore, in order to eliminate the macro virus, you need to determine if your computer system has a virus. To do this, you need to look for signs of infection. A few signs that may mean your computer is being attacked by a virus includes:

• Your computer runs slower than normal.

• Your computer prompts for a password on a file that doesn't require a password.

• Your computer displays unusual error messages or saves documents as template files.

After you determine whether or not your computer has a virus, there are several temporary fixes that you can use to cure it, so you're computer can return to its normal state. Once this is completed, it's important to take preventative measures to stop another macros virus from attacking your computer again.

How Can I Prevent a Macro Virus?

There are several methods you can use to prevent your computer system from becoming infected by a macro virus. Two of these methods include:

• Using digital signatures. Digital signatures are one of the best ways of protecting your computer from macro viruses. These signatures will identity the source of a download or an author of a file so you know whether the files you're downloading and running on your computer are from trusty source and whether the files have been tampered with. It's wise to use or enable as many of the security features on your computer that you can.

• Checking for regular updates. Regularly updating your security programs on your computer will better protect you from new types of macro viruses being created.

Protecting Yourself from Computer Viruses

From the subtle Trojan horses to those pesky little worms, there are many different types of viruses that attack your computer. While each virus has its own feature and the way it damages your computer, almost all of them work in the same way in that they spread from computer to computer.

Viruses are known to fall into 3 main categories: Boot sector viruses, file infectors and macro viruses. Boot sector viruses most commonly spread via floppy disks while file infectors attack via program files. Viruses attach themselves to files and find a way to attack. Macro Viruses on the other hand which are the most common cause the least damage. They infect applications such as Microsoft Word and insert unwanted words in between text.

So, why are these viruses created and what's the best way to protect yourself from them?

Well, in order for the viruses to attack your computer, there is always somebody who writes the virus and someone who has a reason to. Many of the virus writers are men, most of them university students, professors, computer store managers, and doctors who write for different reasons including pranks, research projects, vandalism, identity theft etc. These are some of the most common reasons.

So, the best way to protect yourself from these viruses and virus writers is to be aware. Upload and use anti-virus software programs to keep your computer safe and secure. When you receive emails, be aware of what you open even if it is from people you know. A majority of viruses are transmitted via emails and you should take great precaution when you receive attachments and forwarded emails. If you weren't expecting an email or receive an email from someone whom you don't recognize, delete it right way.

Another way to protect your computer from viruses is to check for updates for all your anti-virus software programs regularly. It is very important that you update your antivirus software so that it can recognize new viruses. If you don't update, your program will not recognize new viruses. So, updating your software regularly is very important if you want your computer to be free from viruses.

Finally, be sure to check if you have installed your antivirus software correctly on your computer. Many people fail to check and sometimes find that their programs don't work at all on their computer.