Classification of computer viruses. Available about complex

Viruses are called a special kind of computer programs containing the so-called malicious code. The classification of computer viruses, discussed below, is very extensive. One thing can be said with certainty - the characteristic feature of all malicious programs is their ability to multiply. Among other things, viruses are dangerous because they are able to perform various arbitrary actions without the user's knowledge, thus damaging the computer software.

So, computer viruses. The classification of them somewhat resembles the careful and detailed systematization of biological prototypes. Computer viruses need to bring them into a certain system. It is possible to do this, taking as a basis the following characteristic features:

- habitat;

- a way to infect this very habitat;

- various destructive possibilities;

- characteristic features of the mechanism of action of the virus.

Now I'll tell you about each feature in more detail.

Habitat. Classification of computer viruses

They should be divided into the following categories:

File viruses. They have the ability to be embedded in operating files. For example, * .BAT, * .DLL, * .SYS, * .EXE, * .COM.

Bootable viruses. Invade the disk boot sector (Boot-sector) or in a special sector, which includes a system boot loader, the so-called Master Boot Record.

Viruses-macro. They are installed inside the system and use so-called macros (for example, Excel, Word).

Also, we should not forget that there are also combined viruses. Typically, they belong to the file-boot type and infect not only the files themselves, but also the boot sectors. In most cases, such viruses have a fairly complex mechanism of action, and are often designed in such a way as to penetrate the system in as much as possible by the original method, in order to prevent their rapid detection.

Ways of infection. Classification of computer viruses

Resident. In memory, they leave their resident part. After a while, it starts completely controlling the operating system. These viruses remain active until the device is rebooted or turned off.

Non-resident. They are practically an exact copy of the previous ones, but memory does not infect, and only a certain, as a rule, limited period of time remains active.

Classification of computer viruses, given their destructive capabilities

Harmless. Absolutely does not affect the operation of the device. The only negative - very quickly spread and reduce the amount of free memory on the hard disk.

Not dangerous. Affect the amount of free memory, and can also attract attention with various effects, usually sound or graphic.

Dangerous. Causes serious failures in the operation of systems.

Superfine. Lead to the loss of various programs, destroy data, erase the information necessary for the full operation of the device.

Types of computer viruses depending on the mechanism of its action

The viruses are companions. Create satellite files for EXE files. The name remains the same, but the extension changes to COM. Typically, when you run a file of this kind, DOS first detects and executes the COM file, i.e. virus.

Viruses are "worms". They are one of variants of companion viruses. Create their own copies, the COM-EXE reception does not apply.

Parasitic malware. This includes all those viruses, which for some reason can not be attributed to either the first or the second sections of this group.

Network viruses. They are famous for the ability to get into the computer through the network and send out their copies. Do not access the resources of the device.

Polymorphic viruses. Do not contain a constant stake site, constantly changing, therefore, belong to the category of those that are difficult to detect.

Macro viruses. Infect programs written in any one specific language.