The first computer viruses appeared immediately after the creation of computers. Programmers wrote them just for fun, such viruses did no harm. But modern computer viruses are created with completely different goals and pose a serious danger. What are the viruses and how to deal with them?
All malware that exists today can be divided into two categories: viruses and Trojans. The former simply perform some kind of negative or comic actions on the infected computer, for example, they can erase files or completely format the hard drive, turn off the computer, make the mouse inaccessible to the user, display some message on the screen, etc.
As a rule, the creators of viruses do not pursue selfish goals, most often such programs are written just for fun. But there are exceptions - for example, viruses that block the operation of Windows.
The user sees a message in which he is invited to transfer some amount of money to a specific account, after which he will be sent an unlock code.
Having met such a virus, you should remember the features of the message, in particular, the account number or phone number (if it is proposed to replenish the phone balance), then go to the sites of anti-virus companies from another computer and look for the appropriate unblocker. But even if it is not possible to remove the virus, the worst consequences of it are formatting the PC hard drive.
Trojans are the biggest threat
This type of malware is created with the aim of stealing a person's sensitive data. If the work of a virus on a computer is usually clearly visible, then the Trojan tries to completely hide its presence. Its task is to collect the necessary information, such as logins, passwords, bank card or online banking data, etc., and then discreetly transfer everything to the owner of the Trojan.
High-quality Trojans are written by highly skilled programmers and can cost thousands of dollars. A well-made Trojan is absolutely invisible; it cannot be detected by any anti-virus program until the information about the Trojan gets into the anti-virus databases.
Modern spyware easily bypasses firewalls. Having done their dirty deed, many Trojans self-destruct without leaving any traces behind. You can find out that your computer has been infected with a Trojan only after you lose money from your bank card, or mailboxes, admin panels of your sites, etc. are hacked.
Backdoors
There is also such a class of viruses as backdoors. By infecting your computer, the virus creates a loophole in it through which the hacker gains full access to the machine. He can view and copy information from disks, delete or add something. A hacker can use your computer to scan networks and break into other computers to attack servers. Thousands of hacked computers can be managed from one center, in which case a botnet is formed - a network of infected computers that are subordinate to one person.
Viruses and Trojans are a huge danger, so they are fought in every possible way. The main problem is that the principles of construction and operation of the most common Windows operating system today provide hackers with a lot of opportunities to create and inject malware.
OS developers are trying to close the gaps, but there are still too many of them. Much more secure in this regard is the Linux operating system, and it is not by chance that many hackers use it.
In any case, to protect against viruses and trojans, the computer must have an up-to-date antivirus and firewall. You should also follow basic security rules - in particular, do not download or open suspicious files.
The concept of a computer virus is familiar to any user. Many people have heard about some "trojans" and "worms" even before they got their first PC. And seasoned computer scientists always install an anti-virus program first of all, so that the system is as protected as possible from malicious files that enter the machine from the outside. And if earlier, when the Internet was not yet so developed, the same viruses infected computer after computer, but they knew how to deal with them. But now, with the development of the network, the range of malicious programs is growing not by the hour, but by the minute, and it is becoming more and more difficult to deal with them. Not without reason, antivirus databases are updated every day.
But still, what is a computer virus? And is it airborne? If you look into various thematic encyclopedias, then they have a clear concept.
A virus is malware that can breed in any operating system, destroying some important files, making changes to existing programs.
In a word, they "dirty" on users' computers. Ultimately, it becomes impossible to work with such a machine, the PC starts to slow down, behave strangely, frustrating its user in every possible way. Viruses work like surgeons - they penetrate into the source codes of files and already there they carry out their malicious operations.
The industry of creating viruses began to develop actively with the advent of the Internet, since it is easiest for hackers to do their "dirty deeds" on the World Wide Web. The goals pursued by malware creators are very different. Someone does it for the sake of interest, to practice writing programs. Most often, such "worms" do not pose a particular threat to the system, however, the creator himself does not always imagine what his virus is capable of, therefore a harmless "worm" can sometimes become a real monster devouring system resources. The second category of people involved in the production of malicious programs pursues completely different goals, more specific ones - stealing personal information from computers. Such viruses pose the greatest danger, since they are able to steal logins, passwords from some services, social networks, or, much worse, from payment systems. The result is a hacked account, stolen money from electronic wallets and other unpleasant consequences.
Despite the huge number of viruses, among them there are the most famous ones that have infected a significant number of computers. The most "romantic", but also one of the most dangerous "worms" was written by some Filipino guy. The hacker called his creation "I love you". The essence of the virus was that it used the mail service to send letters to everyone in a row, in the subject line of which it was written “I love you”, and the attached file contained the “worm” itself, which was stealing passwords. "Love plague" swept almost the entire computer world in 2008. According to various sources, the damage from the Trojan amounted to several hundred million dollars.
Many users consider computer viruses to be either a completely useless, empty application that does nothing, or a program that “explodes monitors”, disables power supplies and takes all the money from the balance of a current bank account.
In this article, we will try to figure out what to expect from a computer virus and what not.
Despite the fact that viruses cannot currently use PC components deeper than operating systems, there is a non-zero chance that one day such viruses may still appear. They will know how to directly communicate with devices in order to transfer them to technological modes or change something directly in the firmware or settings. The most vulnerable link in this regard at the moment is your hard drive.
Virus problems can be very diverse: some can be eliminated, some cannot. Almost all of these complications can be avoided, or at least minimized. To do this, it is enough to have a working antivirus with up-to-date databases in the system.
Alexey Gavrilenko
Reprinting of materials is allowed only with an active link to the original article
Today, almost everyone is familiar with the word virus. We constantly meet with him in life, although we don’t really want it ourselves. In the modern era of computer technology, there are also computer viruses that infect a computer and can cause a lot of trouble. Many people ask: “ What is a computer virus? And how can you fight it? A huge number of books and many articles have been written on the topic of virology.
Thousands of specialists in hundreds of different companies are fighting computer viruses. At first glance, it seems that the topic of protection against computer viruses is not so relevant and complex as to be the object of close attention. But this is absolutely not true. Computer viruses are one of the most common causes of information loss today. There have even been cases when computer viruses blocked the work of enterprises and organizations. Moreover, a case was recorded when a computer infected with a virus caused the death of a person. It happened in one of the hospitals in the Netherlands. The patient died due to a lethal dose of morphine. A stationary computer infected with viruses gave incorrect information.
Today there are many different viruses. Each type of which can be programmed for certain actions and transmitted in the same way in a certain way. Depending on what is written in the main code of the virus, it will operate within a certain time frame and perform strictly defined functions.
A computer virus can:
A computer virus can cause the loss of important information, so you should always remember to protect your computer from unauthorized access and virus attacks. The most important thing is that a simple user, without the help of special programs, will not be able to do this. The virus can be on the computer and not show any signs until some condition (also written in the code) occurs, it can be: a signal from outside, the onset of some date, etc. To protect your computer from the possibility of losing information due to the actions of computer viruses, it is recommended to install anti-virus programs.
It should be emphasized that it is necessary to install these programs immediately after installing the operating system and drivers. That is, it should be the first program that you install on your computer. In addition, today even an installed anti-virus program can be affected by a virus, so it is recommended to scan your computer at certain intervals with special anti-virus programs that are not installed - portable versions.
Despite the great efforts of anti-virus firms, the losses caused by computer viruses have not fallen at all and reach unprecedented amounts of hundreds of millions of dollars annually. And this is clearly an underestimation of itself, since only a small part of such incidents is known.
Therefore, it is necessary to make every effort to protect the computer, and, consequently, all information, from the effects of various computer viruses.
From it you will learn:
Computer viruses can significantly slow down the performance of your computer and destroy all data on your hard drive. They are capable of constantly reproducing and spreading themselves. Something, reminiscent of these human viruses and epidemics. Below is a list of the ten most dangerous computer viruses in the world.
Nimda is a computer worm/virus that damages files and adversely affects the operation of a computer. It was first seen on September 18, 2001. The name of the virus comes from the word admin, written backwards. Due to the fact that the Nimda worm uses several methods of distribution, within 22 minutes it became the most widespread virus/worm on the Internet. It spreads by e-mail, through open network resources, shared folders and file transfers, as well as through browsing malicious websites.
Conficker is one of the most dangerous and well-known worms targeting computers running Microsoft Windows operating systems. Linux and Macintosh systems are completely resistant to it. It was first detected online on November 21, 2008. By February 2009, Conficker had infected 12 million computers worldwide, including government, corporate and home computers. On February 13, 2009, Microsoft offered a $250,000 reward for information about the creators of the virus. A special anti-Conficker group was even created, which was unofficially dubbed the Conficker Cabal. The damage caused by the malware is estimated at $9.1 billion.
Storm Worm is a backdoor Trojan horse that infects Microsoft Windows operating systems. It was first discovered on January 17, 2007. It is distributed mainly by e-mail with the heading “230 people died as a result of storms that devastated Europe” (230 dead as storm batters Europe), and later with other headings. The file attached to the letter contains a virus that makes an information “hole” in the computer system, which is used to receive data or send spam. An estimated 10 million computers have been infected with the Storm Worm malware.
Chernobyl is also known as CIH, a computer virus created by Taiwanese student Chen Ying Hao in June 1998. Works only on computers running Windows 95/98/ME. It is considered one of the most dangerous and destructive viruses, because once activated, it can damage BIOS chip data and destroy all information from hard drives. In total, about 500,000 personal computers around the world were affected by Chernobyl, the losses are estimated at $ 1 billion. Chen Ying Hao, the author of the virus, has never been held accountable and now works at Gigabyte.
Melissa is the first email macro virus that has infected about 20% of all computers worldwide. First seen in March 1999. The malware was sent to the first 50 Outlook Express addresses. The letter had a LIST.DOC file (a virus) attached, allegedly containing passwords to 80 paid porn sites. The program was invented by David Smith from New Jersey. On December 10, 1999, he was sentenced to 20 months in prison and fined $5,000. While the damage caused by the virus amounted to about $ 80 million.
SQL Slammer is a computer worm that generates random IP addresses and sends itself to those addresses. On January 25, 2003, it hit Microsoft servers and another 500,000 servers around the world, which led to a significant decrease in Internet bandwidth, and generally disconnected South Korea from the Internet for 12 hours. The slowdown was caused by numerous routers crashing, burdened by extremely high outbound traffic from infected servers. The malware spread at an incredible speed, infecting about 75,000 computers in 10 minutes.
Code Red is a specific type of computer virus/worm that attacks computers running the Microsoft IIS web server. It was first detected on July 15, 2001. This malware basically replaced the content of the pages on the affected site with the phrase "HELLO! Welcome to http://www.worm.com! Hacked By Chinese! In less than a week, code red hit more than 400,000 servers, including the White House server. The total amount of damage caused by the virus is about $2.6 billion.
Sobig F is a computer worm that infected about a million computers running Microsoft Windows operating systems in 24 hours on August 19, 2003, thus setting a record (although it was later beaten by the Mydoom virus). Distributed by e-mail with an attachment. Once activated, the virus looked for addresses on the infected computer and sent itself to them. Sobig F itself was deactivated on September 10, 2003, and Microsoft promised $250,000 for information about the creator of the virus. To date, the perpetrator has not been caught. The damage caused by the malware is estimated to be $5-10 billion.
Mydoom is a mail worm that infects computers running Microsoft Windows. The epidemic began on January 26, 2004. The malware began to spread very quickly using e-mail, a letter with the subject "Hi", "Test", "Error", "Mail Delivery System", "Delivery Notification", "Report Server", which had an attachment. When opened, the worm sent itself to other addresses, and also modified the operating system in such a way that the user could not access the sites of many news feeds, anti-virus companies, and certain sections of the Microsoft site. The virus has also created a huge load on Internet channels. Mydoom contains the text message "Andy, I'm just doing my job, nothing personal, sorry." Was programmed to cease distribution February 12, 2004.
ILOVEYOU is a computer virus that has successfully infected more than three million personal computers running Windows. In 2000, it was distributed by e-mail, a letter with the subject "ILOVEYOU" and the attachment "LOVE-LETTER-FOR-YOU.TXT.VBS". After opening the application, the worm sent itself to all addresses from the address book, and also performed numerous changes in the system. The damage caused by the virus is $ 10-15 billion, which is why it was listed in the Guinness Book of Records as the most destructive computer virus in the world.
