Updated May 30, 2023
Introduction to Types of Computer Virus
We will see an outline of types of Computer Viruses. A computer virus is a simple malicious code that hackers design to fetch data from the user. A computer virus self-replicates by doubling itself into another program, spreading itself into the document, and taking control of that document and sensitive data. The general method to spread computer viruses as executable files are by email. If the user opens the email and clicks on the file, the virus enters the system, affecting its performance. A computer virus is also spread using USB drives, storage disks, and removable hard disks. It is a serious issue that has to be taken action by installing an antivirus program.
Different Types of Computer Virus
Computer viruses occur in various kinds to affect the system differently.
1. Boot Sector
The boot sector virus affects the master boot record, and it is a difficult and tough task to remove the virus and frequently requires the computer to be formatted. It is generally spread through removable disks.
2. Direct Action
Direct action virus is installed in hidden or retrieved under the computer memory, also called non-resident virus. It acts as a parasitic and is attached to a considerable file that wants to be affected. But it does not disturb the user’s experience and the system’s performance.
3. Resident
The resident virus is installed on the system, and it is very difficult to find it and eradicate the computer virus from the system. It gets stocked to computer memory and can affect the performance of the system. The resident viruses are bothersome due to the reason they can run unnoticed by antivirus software by hiding in the system’s RAM. After the original virus is erased, the version saved in memory storage can be enabled. It happens when the computer Operating System boots certain applications or functions.
4. Multipartite
The multipartite virus can be spread in numerous ways and simultaneously affect the computer’s boot system and executable files.
5. Polymorphic
Polymorphic virus alters their signature patterns wherever it gets duplicated, and it is difficult to find the affected process. It can convert its attribute into the underlying code without converting the fundamental functions. When a user tends to detect the virus, it can change its modification, and the user can no longer find the presence of a virus.
6. Overwrite
Overwrite virus deletes the infected file, and it is possible to remove and delete the corrupted files, and the user loses all his sensational data. It is mainly spread through emails and is mostly designed to damage the file system or an entire application. As the name portrays, it affects the system by overwriting the files with its code and damaging the system’s performance. On the opposite side, additional files are also executed to affect the other file system and data.
7. Spacefiller Fills
Spacefiller virus fills the space which occurs between the codes and doesn’t affect the file. It is called a cavity virus.
8. File Infector
File infector virus spread through program files and affects the program whenever it is executed as file types. When the file is loaded, the viruses also load along with it. It is also executed whenever the script is loaded.
9. Macro
Macro viruses focus on language commands in Microsoft word. Similar comments are applied to other programs. The macros are keywords that are deployed on sequences for commands. The macro viruses are built to add their malicious code to the macro sequence in a word document. Cyber attackers use social engineering to target the user. The user can enable macros to load the virus. The word document error is overcome in version Office 2016. It can be accessed for trusted work and blocked if required across the company.
10. Rootkit
The rootkit virus is secretly installed as an illegal rootkit on an affected process, opening the gate for hackers and accessing the complete system. The hacker can disable or modify the functions. Unlike other viruses, it is designed to surpass antivirus software. The updated version of vital antivirus involves rootkit scanning. The boot-record infectors affect the code found on a disk’s particular system area. It is attached to USB and DOS boot or MBR on hard disks. But these viruses are not common since they rely on physical storage media.
11. Creeper
Creeper is not a dangerous virus but its self-replication. Once it affects the system, it creates a pop-up message, like catch me if you can.
12. Elk Cloner
Elk Cloner is a boot virus that attacked the Apple system and leaves a poem that the hacker writes3. ILOVEYOU
ILOVEYOU is a virus that caused huge financial damage. The email is disguised as a love letter to anyone in the contact book, and if the user prompts to open it, the virus gets injected into their system. This is popular, which affected fifty million systems in just nine days.
14. Code Red
The Code red virus attacked Microsoft servers and caused many server-related issues as it degraded all the information technology systems. Ninda is a window virus that is injected through multiple methods. It is spread via emails, web browsers, attachments, and different means of portable devices.
15. Slammer
Slammer is an extremely rapid-spreading virus affecting billions of systems in a fraction of a second. The single-bit code that corrupts the entire program later is a type of virus that occurs when there is a program error, but the user receives lots of worthless media with a quote, Bill gates, Stop Making money. Welchia is a virus that affects the computer, then deletes itself.
16. Commwarrior
Commwarrior is an advanced form of virus that attacked smartphones through text messages. It is a new variety of viruses in the beginning stage, so the security is made firm to prevent the user data. The user has to safeguard his device with a strong firewall and antivirus software to prevent the system from any virus attack. The user should cross-check twice before installing a program, clicking on spam emails, downloading a suspicious file, and inserting any hard disk into the system.
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This is a guide to Types of Computer Viruses. Here we discuss the basic concept of different types of Computer Virus-like Boot Sector, Direct Action, Resident, etc. You can also go through our suggested articles to learn more –
