By [http://ezinearticles.com/?expert=Alfred_Clark]Alfred Clark
When a computer gets infected by a virus, there can be normally two possibilities. The first is that the antivirus on the computer is up to the task and prevents it from entering or even weeding it out if it has already entered. The second is that the virus is so complex and advanced or the antivirus is so obsolete that the only way for the virus to be removed is to repair the operating system or even a complete format.
Most people think that if there is a virus on their computer, then they would start to see signs of such an infection. However, what if there was a virus that was so advanced that it did not reveal its presence? Such viruses exist and are widely known as stealth viruses. The following will allow you to learn about such computer viruses so that your computer can be better protected.
What Is The True Nature Of Stealth Viruses?
The first stealth virus was created purposefully by developers and was known as Brain. A stealth virus is a virus that makes it very hard for the user or the antivirus software program from detecting its presence on the computer. The reason for this is fairly obvious. The reason behind why the virus would not want its presence to be revealed is that the longer it goes undetected, the easier it will be to do its task, whatever it may be. Stealth viruses are significantly different from generic viruses because their capabilities of keeping themselves hidden are more advanced.
What Methods Do They Use For Stealth?
There are various methods that stealth viruses employ to keep from being detected. In simple terms, a stealth virus looks to do its mischief i.e. infect a file, modify the boot sector, or affect the partition sector but keep the changes it makes, hidden. One method employed to achieve this is by taking over the system responsible for reading files and sectors. When the system requests to access or read the infected files or sectors, this virus then redirects the system to copies of the original files so as to make it look like nothing has changed.
Another method that stealth viruses use is the disinfect-re-infect method. rel=nofollow [http://mynetworksecuritypage.com/]Stealth viruses based on this method disinfect the infected file or sector every time a request to access them arrives. Subsequently, when the file or sector is closed by the system, these computer viruses infect them again. [http://mynetworksecuritypage.com//]Computer virus, by its nature, have the capability to change things on the computer without revealing it to the user. These types of viruses can be very difficult to detect unless you know how to go about it.
Article Source: [http://EzineArticles.com/?What-Are-Stealth-Viruses?&id=8348754] What Are Stealth Viruses?