In today's virtual world, there are many security threats that pose a threat to users and their data. Over the past several decades, Computer viruses have evolved in a clear and noticeable way and are still in constant change until now, as they change their way of working and their impact on infected devices. In this topic, we will highlight 7 of the most dangerous types of computer viruses. Perhaps some of them have disappeared now, but you must have a background about them.

Computer viruses do not differ from biological viruses that infect humans - may God protect us and you - in terms of their multiple forms and their effect in different ways on the computer. Certainly, over these long years there will not be only one virus that causes concern to users - hundreds and thousands; Each of them has a different mechanism of action.

Of course, when the computer is infected with a virus, the effect will not only be on the operational performance, as this is not the goal that the virus detector pursues, but rather to wreak corruption on the entire computer. This includes: deleting files, stealing data, and hacking other devices on the same network. In order not to prolong the conversation, let us go directly below to identify seven of them that are classified as the most dangerous types of computer viruses ...

Learn about the most dangerous types of computer viruses

The first: the boot sector virus

Any portable storage unit such as hard disks, floppy disks, flash drives, and sometimes CD / DVDs, has a basic part inside it called the Boot Sector. Without this part, it is impossible for your computer to load and boot into the operating system. Therefore, the boot sector virus is one of the most dangerous types of computer viruses. The virus usually replaces the default boot program with a special, corrupted version.

This virus is able to infect the computer and completely paralyze its movement only if it is starting before the operating system is booted. Whereas in other cases, the virus will be booted after or when the computer is turned on, and thus the user will still be able to continue working on the device. And because the virus destroys the boot program on the hard drive, it is difficult to get rid of it and most of the time you will need to completely format it.

This virus is spread on removable storage media such as a USB flash drive. And it began to appear abundantly in the nineties when floppy disks were dominant in the field of storing data on computers. But you can still find it now and via email attachments. But it often will not have an impact on modern computers thanks to improvements in the BIOS architecture that have reduced its spread.

The second: viruses with a direct effect

Direct-acting viruses are divided into two main types: resident viruses and non-resident viruses. The latter does not install itself on the computer and does not remain hidden in the memory - rather it works by identifying one or more folders and infecting the computer every time this folder is opened, so that when certain conditions are met, the code execution begins immediately and acts on the infection. All files in this folder. Fortunately, this virus does not delete anything or affect the computer's performance. Rather, what will happen after infection is some files are corrupted, and you can easily remove this virus with any simple anti-virus program.

Rugrat was one of the early discoveries of a non-resident virus, commonly known as “Win64.Rugrat,” as it was the first virus to infect computers running on Intel Itanium processors. What this virus was doing was trying to infect all executable files (with exe extension) that support 64-bit architecture and destroy them along with the rest of the files in the same folder.

The third: viruses residing in the system

Resident viruses are the primary type of direct-acting virus, they are in complete contrast to non-resident viruses, and the names are self-explanatory. This type of virus is installed on the computer and kept in the memory; Which means that the virus starts working every time the computer is started. Even after eliminating the original source that infiltrated your device. As such, it is considered one of the most dangerous types of computer viruses.

And noticing that your device is infected with the resident viruses depends on the programmed method, which is divided into two types: fast infection and slow infection. The first type causes tremendous damage as quickly as possible and is therefore very easy to detect due to the effects, while it is difficult to recognize a slow infection because its symptoms develop slowly, so you may discover it after a period of infection.

Unfortunately, it is difficult to get rid of resident viruses as they integrate with the operating system and hardware components and thus embed themselves in the computer, and may even be designed to prevent the actions of anti-virus programs, so the programs will not be sufficient to protect you. Mostly, you will be able to eliminate it with a self-boot rescue disk such as Kaspersky Rescue Disk, so that the virus can be extracted from the memory and thus removed from the default operating system. In the worst case, however, you'll need to completely format the hard drive.

Fourth: multi-part viruses

Most viruses spread on the computer through a single method programmed on them, but multi-part viruses have more than one method, and their goal may be to infect the executable files or the boot sector and they can at the same time infect both the boot sector and the executable files together, which causes corruption And damage to the computer more than any other kind, when the computer is infected with this virus, it will not be able to perform even the simplest tasks. It also infects your computer many times and at different times, which makes it difficult to remove. Even if you managed to prevent the infection from infecting the executable files, the virus will still be in the boot sector and every time you start the computer, the virus will run and the installed files and programs will be destroyed.