As computer technology evolved in the last few decades, the number of cyber-attacks has also increased at a rapid rate. Through different methods like hacking, unethical coding, etc. attackers tend to access sensitive and confidential information and use it for getting ransoms or selling them, some times even use it for terrorist attacks. According to the latest reports in every 7 seconds a new malware is released. Shocking right?
Here we are going to discuss different types of malicious computer viruses that can make you and your data at risk whenever you are using the computer.
What Is A Computer Virus?
A computer virus can be defined as a malicious code or a fragment of it embedded into a legitimate program in order to perform malicious actions through spreading from host to host by replicating itself without the user’s knowledge.
In the present day, the term computer virus has become so common that in most cases all we can do is that to sit and wait for what’s coming next. The main reason is that all of us are experts in handling a computer but unware or ignorant about the latest computer viruses that are surfacing online.
Different Types of Computer Viruses
Computer viruses can infect any system mainly through three mediums:
❖ Removable media
❖ Email attachments
❖ Internet downloads
The most common type among the three is through removable media or devices, even though it is the internet that gets a bad reputation for spreading the virus and other malware.
Some of the most commonly seen computer viruses are:
- Boot Sector Virus
- File Virus
- Macro Virus
- Direct Action Virus
- Resident Virus
- Source Code Virus
- Encrypted Virus
- Multipartite Virus
- Stealth Virus
- Tunneling Virus
- Polymorphic Virus
- Rootkit Viruses
- Overwrite Virus
- Armored Virus
- Spacefiller Virus
Let’s See Types of Computer Viruses In Detail
1. Boot Sector Virus
Also known as memory virus this type of viruses are designed to specifically infect the boot sector of the system, which is the Master Boot Record (MBR). This malicious program will get executed with each booting. The boot sector does not affect the file system. It is usually spread through removable media like floppy disks, flash drive, etc.
Eg: Michelangelo, Disk Killer, Stone
2. File Virus
File virus is also known as a program virus or parasitic virus. This virus affects executable program files through appending itself to the end of the files. It changes the start of a program and this makes the control jumps to its code until the execution. It affects files with extensions.COM, .EXE, .OVL, .DRV etc.
Eg: Cascade, Sunday
3. Macro Virus
It is one of the relatively harmless viruses out there. It is written in high-level languages, unlike other viruses. The macro virus gets triggered only when an application capable of executing it is started or running, for example, MS Word, Spreadsheet etc. It is also known as the Document virus.
Eg: Word Concept, Melissa Worm
4. Resident Virus
These viruses can install themselves as apart of the operating system. That means they can execute even when the original source is exterminated. Because of this, the experts consider the Resident virus as one of the dangerous computer viruses.
Eg: CMJ, Meve, Randex
5. Direct Action Virus
Also known as Non- Resident virus is exactly opposite to Resident virus. That is it gets spread to other existing files and becomes inaccessible once it is executed. Even though this malicious software can affect computers applications, it won’t affect the total user experience.
Eg: Vienna virus
6. Source Code Virus
Source Code viruses are a type of computer virus that are designed to make modifications to source code. Actually what this virus does is that it will drop a Trojan code into any ASM and PAS source file in the system. It is one of the rarest viruses since it is difficult to write source codes for different types of languages and compilers available today.
Eg: Die Hard
7. Multipartite Virus
This virus as the name indicates affects multiple parts of the system (booting, file systems, memory, etc. )and remains repeatedly infecting each part. This very difficult to find these and also if not eradicated or contained effectively it will reinfect again and again.
Eg: Ghostball, Flip
8. Stealth Virus
The stealthy virus or ‘tricky’ virus is smart when it comes to hiding itself during virus detection. It will some times eliminate itself from memory during detection or even changes the code that is used for detection.
9. Encrypted Virus
The encrypted virus will remain in an encrypted form so that it can escape the virus scanning. When it comes time for execution, it will use the description algorithm within it.
Eg: W32/[email protected]
10. Tunneling Virus
The tunneling virus will try to intercept anti-virus software to interrupt detection. As a result, the interception programs will be disabled.
11. Polymorphic Virus
The polymorphic virus changes its virus signature (a pattern used to identify a particular virus) to remain undetected without affecting its functionality.
Eg: Phoenix, Evil, Virus 101
12. Rootkit Viruses
Rootkit viruses can hide undetected inside the affected system which affects its performance. It will install an illegal rootkit which will provide access to the attackers so that they can gain control over the various functions of the infected system.
13. Overwrite Virus
This type of viruses will start overwriting a file or application once it is executed, destroying the original codes. This is also used for ethical purposes where this virus can installing a new code in the files or applications in order to update its features.
Eg: TRj. reboot virus
14. Armored Virus
The armored virus makes use of its specifically designed coding mechanism to avoid being detected by anti-virus mechanisms. Sometimes it will mask itself or will give the wrong location information or find any way to escape even from the eyes of virus experts.
Eg: Whale virus
15. Spacefiller Virus
Spacefiller virus or Cavity virus installs itself in between empty spaces of a file without changing its size. This way the virus can stay undetected by antivirus detection.
Eg: Lehigh virus
Wrapping Up: Types of Computer Virus & Malware
These were the most common viruses list that mainly infected in less secure computer system, to be always on the safe side then make sure you are using the best antivirus protection that will be enabled safeguard to not enter any types of virus or malware, moreover, in the technology world every day there are lots of unique different types of viruses are produce by hackers to infect and steal your private information in many ways. So it’s great to know about those viruses.
Let us know in comment section Is there any different viruses that infect your computer system?