Here are 10 types of computer viruses, explained with insights from various sources:
Computer viruses are malicious programs that can replicate themselves and spread to other computers, causing damage and disruptions. Understanding the different types of viruses helps to protect systems more effectively.
10 Types of Computer Viruses
| Virus Type | Description | Common Effects | Example |
|---|---|---|---|
| 1. Macro Virus | These viruses are written in a macro language, often found in documents or spreadsheets, like those in Microsoft Office. | They typically activate when a file with embedded malicious macros is opened, potentially leading to data loss or system compromise. | Document viruses in Word. |
| 2. Boot Sector Virus | These viruses infect the boot sector or master boot record of a storage device, making it challenging to remove them. | When a system starts, the infected boot sector loads the virus first, potentially taking control over the entire boot process and system. | Old system startup problems |
| 3. Trojan Horses | Unlike other viruses, Trojans do not replicate. They masquerade as legitimate software, but once executed, they perform malicious activities. | Trojans can be used to steal data, create backdoors for attackers, install malware, or even delete files. | Banking Trojans, Remote Access Trojans |
| 4. Overwrite Virus | These viruses overwrite data on the disk, making the original content inaccessible or damaged. | The infected files can become useless, making it difficult to recover the original information, leading to data loss and system instability. | File-overwriting malware. |
| 5. Browser Hijacker | These viruses change browser settings, like default search engine or homepage without the user's knowledge. | They can redirect searches to malicious sites, display unwanted advertisements, or gather browsing data for malicious purposes. | Toolbar modifications. |
| 6. Web Scripting Virus | This type of virus takes advantage of security vulnerabilities in web browsers or web applications. | Web scripting viruses can be used to steal personal information, spread malware or manipulate website content. | Cross-Site Scripting (XSS) attacks. |
| 7. Polymorphic Virus | Polymorphic viruses change their code each time they replicate, making them hard to detect using signature-based antivirus software. | This technique makes it difficult for antivirus software to recognize and remove these viruses. | Sophisticated malware evolution. |
| 8. Resident Virus | This virus installs itself in a computer's memory, and it will infect any file that is accessed or executed from that point. | It operates in the background, causing continuous infection of files and system performance degradation. | System level resident malware |
| 9. File Infector Virus | This type of virus infects the executable files, like .exe or .com files by modifying the file code. | Whenever the infected file is executed, the virus also executes, leading to system damage. | Executable file infection. |
| 10. Multipartite Virus | This type of virus can infect a computer through multiple means, like infecting files, boot sectors, or macro locations making it challenging to remove. | The combination of infection vectors makes it difficult to remove completely and may require specific tools for remediation. | Sophisticated malware with multiple infection vectors. |
Understanding these various types of computer viruses is essential for implementing robust security measures and protecting computer systems against potential threats.
