Shulou(Shulou.com)06/03 Report--

In this issue, the editor will bring you about what is the necessary conditions for computer virus transmission. The article is rich in content and analyzes and narrates it from a professional point of view. I hope you can get something after reading this article.

The necessary conditions for computer virus infection are "running virus programs in computer memory" and "reading / writing to disk". The main ways of transmission are: 1, network communication, including the Internet and local area network; 2, mobile media transmission, such as U disk, mobile hard disk and so on.

Computer virus (Computer Virus) is clearly defined in the regulations of the people's Republic of China on the Security and Protection of computer Information Systems. Virus refers to "a group of computer instructions or program codes inserted by programmers in computer programs that destroy computer functions or data, affect computer use and are capable of self-replicating."

Different from the "virus" in medicine, computer virus does not exist naturally. It is a set of instructions or program code compiled by some people using the inherent fragility of computer software and hardware.

It can lurk in the computer storage medium (or program) through some way, is activated when it reaches certain conditions, and puts its own exact copy or possible evolution form into other programs by modifying other programs. thus infecting other programs and destroying computer resources, the so-called virus is man-made and does great harm to other users!

Characteristics

Reproduction

A computer virus can reproduce like a biological virus, and when a normal program runs, it also replicates itself. whether it has the characteristics of reproduction and infection is the first condition to judge that a certain program is a computer virus.

Destructive

After the computer is poisoned, it may cause the normal program not to run, delete the files in the computer or be damaged to varying degrees. Usually manifested as: add, delete, change, move.

Infectivity

Computer viruses are not only destructive in themselves, but also contagious. Once the virus is replicated or mutated, its speed is difficult to prevent. Infectivity is the basic characteristic of the virus.

In the biological world, viruses spread from one organism to another through infection. Under appropriate conditions, it can reproduce in large numbers and cause infected organisms to show symptoms or even death.

Similarly, computer viruses can spread from infected computers to uninfected computers through various channels, causing the infected computers to malfunction or even paralyze in some cases.

Unlike biological viruses, a computer virus is a piece of artificial computer program code. once this program code enters the computer and can be executed, it will search for other programs or storage media that meet its infectious conditions. determine the target and then insert your own code into it to achieve the purpose of self-reproduction.

As long as a computer is infected, if it is not dealt with in time, the virus will spread rapidly on this computer, and the computer virus can infect other computers through various possible channels, such as floppy disk, hard disk, removable hard disk, and computer network.

When you find a virus on a machine, the floppy disk that is often used on that computer has been infected with the virus, and other computers connected to this machine may also have been infected with the virus. Whether it is contagious or not is the most important condition to judge whether a program is a computer virus.

Latent property

Some viruses are like ticking time bombs, and when they attack is designed in advance. For example, the Black Friday virus, which is not detected at all until the scheduled time, suddenly explodes and destroys the system when the conditions are in place.

A well-written computer virus program usually does not attack immediately after entering the system, so the virus can quietly hide in the disk or tape for a few days or even years, once the time is ripe to get the opportunity to run, it will have to multiply, spread, and continue to harm.

The second manifestation of latent nature is that there is often a trigger mechanism inside the computer virus. When the trigger condition is not met, the computer virus does not do any damage except infection.

Once the trigger conditions are met, some display information, graphics or special identifiers on the screen, while others perform operations that destroy the system, such as formatting the disk, deleting the disk file, encrypting the data file, locking the keyboard and deadlock the system.

Concealment

Computer viruses have strong concealment, some can be detected by virus software, some can not be detected at all, and some are sometimes hidden and changeable, which is often difficult to deal with.

Touchability

The characteristic of a virus that induces a virus to infect or attack due to an event or value is called triggering. In order to conceal itself, the virus must lurk and do less action.

If it does not move at all and lurks all the time, the virus can neither be infected nor destroyed, and it will lose its lethality. To conceal and maintain its lethality, the virus must be triggering.

The trigger mechanism of the virus is used to control the frequency of infection and destruction. Viruses have predetermined trigger conditions, which may be time, date, file type, or some specific data.

When the virus is running, the trigger mechanism checks whether the predetermined conditions are met, and if so, initiates the infection or destruction action to make the virus infect or attack; if not, make the virus continue to lurk.

The transmission of the virus can be roughly divided into two types:

One is network communication, including the Internet and local area network, and the other is mobile media transmission, such as U disk, mobile hard disk and so on.

The details are as follows:

(1) hard disk transmission: because the infected hard disk is used locally or moved to other places, maintenance, etc., is infected by the virus and spreads it.

(2) CD transmission: most of the software is burned on the CD. Because ordinary users buy less genuine software, some illegal businessmen put the software on the CD and burn the virus files on it in the process of copying.

(3) U disk transmission: U disk is easy to carry. In order to facilitate the transfer of files between computers, U disk is often used to spread the virus from one computer to another.

(4) downloading virus files on the network. Today, with the increasing popularity of computers, people transmit files and letters to each other through computer network, which speeds up the spread of the virus, because of the sharing of resources. people often download online, free sharing software, virus files are inevitably entrapped among them, Nino is also the main way of modern virus transmission.

The above is what the editor shares with you what is the necessary condition for computer virus transmission. If you happen to have similar doubts, you might as well refer to the above analysis to understand. If you want to know more about it, you are welcome to follow the industry information channel.

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