It’s often said that coders can make or break the internet. They create the Internet by building great apps, websites, software, etc.; they can also damage it through malicious programs like viruses. Computer viruses are one of the topics most frequently discussed by regular computer users. You must have found yourself debating this topic one way or the other. However, many don’t know the details about computer viruses.
As such, we must give a detailed explanation of the life and activities of computer bugs. This piece will also explain if a computer virus can remain undetected or affect human beings. If you understand how viruses operate, you will be equipped to deal with them appropriately.
What is a computer virus?
A computer virus is a malicious code or a program written to accomplish specific objectives, such as altering a program or spreading itself from one system to another. When transferred to a technological device, a computer virus can cause harm, such as stealing data or destroying a device!
Some define a computer virus as anything capable of attacking a computer. However, a computer virus’s activity goes beyond merely attacking a system. It can attack hard disks, the operating system as a whole of a computer, or parts of any electronic device.
Computer viruses can also be likened to biological viruses that attack humans. Their effects and operation are similar to viruses spread in humans and devices. Both are not invited but infect their hosts to cause harm. Computer viruses can self-replicate by attaching to other programs and spreading across devices. The UK IT Governance recorded a whopping rate of 20 billion cyber attacks in 2020. Such attacks were aimed at different things, but the underlying effects were devastating damages.
To view a concise version of this article, we invite you to watch our video on the same topic.
Definition and Types of Computer Viruses
A computer virus is a malicious software (malware) designed to replicate itself by attaching to other programs or files on a computer. The primary function of a computer virus is to cause harm to the infected computer system, steal sensitive information, or disrupt the normal functioning of the computer. There are several types of computer viruses, each with unique characteristics and methods of operation:
Boot Sector Viruses: These viruses infect the boot sector of a computer’s hard drive, making it difficult to start the computer. They are particularly troublesome because they activate before the operating system even loads.
File Viruses: These viruses attach themselves to executable files on a computer, causing them to malfunction or crash. The virus is activated when the infected file is run and can spread to other files.
Macro viruses target macro-enabled applications, such as Microsoft Word or Excel. They can damage documents and files by executing malicious code when the application is opened.
Multipartite Viruses: These versatile viruses can infect a computer’s boot sector and executable files, making them difficult to remove.
Polymorphic Viruses: These viruses can change form and structure, making them difficult to detect and remove. They modify their code each time they infect a new computer, evading traditional antivirus software.
Stealth Viruses: These viruses can hide from the operating system and antivirus software, making them difficult to detect. They often disguise their presence by intercepting and altering system functions.
Trojan Viruses: Disguised as legitimate programs, Trojan viruses contain malicious code that can harm the computer. They often trick users into installing them, thinking they are helpful software.
Worm Viruses: Unlike traditional viruses, worms can spread from computer to computer without human interaction. They can cause widespread damage and disruption by exploiting network vulnerabilities.
Understanding these computer viruses can help you recognise potential threats and take appropriate measures to protect your computer system.
How does a computer virus spread?
Computer viruses spread through files downloaded from the Internet, particularly from email attachments and unofficial file-sharing sites. They can also be spread by browsing infected websites and engaging in social engineering-based scams (such as using a voice call to browse a website or a malicious USB).
To understand the dangers of a computer virus, one common trait is that it can replicate through network sharing. As such, its transfer mode can be through network sharing or electronic mail. It can also infect a system through a file while downloading it online without protection software. After this, such a virus can replicate and carry out destructive works. It can also attach itself to executable files, infecting the systems and networks.
It is not uncommon for many computer users to think that a computer virus is the same as a computer worm. Viruses are different from worms, spyware, and rootkits. However, all can be classified as examples of malicious software or codes. All these types of malware have a standard function, making it impossible for your system to operate effectively.
Most viruses spread through the web and email traffic. Users browsing the web may unintentionally download malicious programs in nature, click on the links in the email or execute email attachments, leading to virus infection on the underlying computer system. In advanced mode, viruses can bypass security protections. These are often with the use of security applications or network-level access controls.
How Do Computer Viruses Work?
Computer viruses work by attaching themselves to other programs or files on a computer and replicating themselves. They can spread through various means, including:
Infected Software Downloads: Downloading software from untrusted sources can introduce viruses to your computer. Always ensure you download software from reputable websites.
Infected Email Attachments: Opening email attachments from unknown or suspicious sources can lead to virus infections. Be cautious with email attachments, especially if they come from unfamiliar senders.
Infected Websites: Visiting malicious websites can automatically download viruses. To block such threats, ensure your web browser security settings are current.
Infected USB Drives: USB drives connected to infected systems can transfer viruses to your computer. Always scan external storage devices before accessing their contents.
Network Vulnerabilities: Viruses can spread from one computer to another by exploiting weaknesses in network security. Ensure your network is secure with firewalls and updated security protocols.
Once a virus infects a computer, it can cause a range of problems, including:
Slow Computer Performance: Viruses often run background processes that consume system resources, leading to sluggish performance.
Frequent Crashes: Infected systems may experience frequent crashes or become unresponsive because the malicious code interferes with normal operations.
Unusual Error Messages: Unexpected error messages or pop-ups can indicate the presence of a virus.
Unexplained Changes to Computer Settings: Viruses can alter system settings, leading to changes in the appearance or behaviour of your computer.
Pop-up Ads or Unwanted Software: Some viruses generate ads or install unwanted software without your consent.
Understanding how computer viruses work and recognising the symptoms of an infected system can help you take steps to protect your computer and prevent their further spread.
What harm can a virus do to your computer?
Writers of malicious software like computer viruses have their reasons for doing such –a deliberate effort to attack your PC. The writer intends to determine the harm the virus can cause when it inhabits your system. The following are the harms a computer virus can do to your computer system;
Damage and corrupt files
Resident viruses can access and utilise computer memory while remaining inactive until certain conditions are met.
One primary function of a commuter virus is to damage the file on the host computer. A computer virus can corrupt any file available on the hard drive. Unfortunately, any file corrupted by a computer virus cannot be recovered as it has been rendered useless. The file can be any type, including documents, audio, video, and applications.
Slow down the performance of your computer
Removing computer viruses involves specific steps to eliminate them effectively. The process can be challenging, especially with sophisticated forms that may require professional assistance.
A computer virus operates in the background. However, this operation affects the performance of your operating system, especially Windows. The virus slows down the computer’s speed, making your system perform poorly and causing programs to take longer to respond.
Missing files on the computer’s hard disk
Aside from the fact that a computer virus can corrupt your files, such malicious code on your computer system can also result in the incessant disappearance of files. The virus can send the file to the writer or permanently delete the files from your system.
Misbehaviour of computer programs and applications
Some applications or even the computer can start displaying irrelevant messages when attacked by a virus. High-profile hackers have used this method.
Likewise, you may realise some programs are running by themselves without a command from the user. This is another way to identify that your commuter is under a virus attack. Sometimes, the virus may replace all available files on your system without your permission.
Viruses are written in various languages to infect Windows and Linux operating systems. We come across another myth about viruses on Mac systems. Simply:
Can Mac computers get viruses?
Yes. Like other computer systems, viruses can infect Mac computers. Some examples include FakeFileOpener, ThiefQuest, and BirdMiner. We have previously shared computer virus facts and ridiculous myths articles.
Steal information
Cybercriminals program computer viruses to carry out cybercrimes. Viruses created by such people can steal your data and send it to the creator. Information like your name, credit card details, and sensitive information kept on your computer can be the target of a virus. This is why having antivirus software is essential on every business computer.
Can computer viruses go undetected?
A computer virus can go unnoticed because it can hide in a system in several ways. Most of the time, the virus’s activity on the computer announces its presence. On the other hand, it may be detected by antivirus software. However, it is still possible for a computer virus to be present on your computer without showing symptoms.
Computer viruses that regularly steal and send your info to the originator are always decisive. They may remain in disguise for a long time without being detected. Such a virus aims to constantly feed the developer with your data and information without your notice.
This, however, is possible when your virus protection is out of date. A good antivirus must be up-to-date and identify the latest strings and signatures of viruses. A virus created with a new signature may remain undetected by an antivirus that identifies an old signature. See some of the ways viruses hide:
Attached to system files (CCriticalfiles that are part of your computer’s operating system) without changing anything in the system files.
Self-encrypting. This means the virus can convert (information or data) into a code and prevent users or antivirus software from accessing it without due permission from you, the user.
Morphing: Virus detectors can’t detect a morphing virus because it changes its code each time it infects a new computer. Some viruses change their code in the infected system every few hours. There’s also the polymorphic virus, which produces various but operational copies of itself.
A dynamic or patient virus is designed to attack only when there is a vulnerability.
What is the most harmful computer virus?
Ransomware is the latest kid on the virus block and a deadly one for businesses.
Ransomware attacks are malicious software that locks victims out of their systems or files and requires them to pay a ransom to regain access.
Different forms of computer viruses with different operations have been reported worldwide. The activity of computer viruses includes stealing information, damaging the computer system, and more. It is, therefore, wise to say that all computer viruses are harmful. However, the level of damage caused is different.
Norton UK has reported Cryptolocker (Ransomware) as the most dangerous computer virus. It was released in Sept 2013 and locked user files after infecting users through email attachments. This is based on the damages caused and the rate at which the virus went viral. Cryptolocker, when it takes over your computer, encrypts all your files and restricts access. After this, you must pay a Bitcoin levy to retrieve those files.
Other examples of viruses notable for great harm are;
PlugX
Zeus Gameover
ILoveyou Virus
Mydoom
Stuxnet
Slammer
Examples of Harmful Computer Viruses
There have been several high-profile examples of harmful computer viruses in recent years, highlighting the importance of robust virus protection:
WannaCry Virus: This ransomware virus affected millions of computers worldwide, causing widespread disruption. It encrypted user files and demanded a ransom for their release, significantly impacting businesses and individuals.
NotPetya Virus: The NotPetya virus targeted businesses in Ukraine and caused significant damage by encrypting files and rendering systems inoperable. It spreads rapidly through network vulnerabilities, affecting companies globally.
I Love You Virus: This virus spread rapidly through email attachments, causing widespread disruption. It overwrote files and sent copies of itself to all contacts in the victim’s email address book.
These examples underscore the importance of taking proactive steps to protect your computer from viruses and other types of malware. Regularly updating your antivirus software and practising safe browsing habits can help mitigate the risk of infection.
Can computer viruses affect humans?
The thought that a computer virus can affect humans sounds absurd, isn’t it? However, if you can look into the advent of technology in the medical field, you will realise it is possible. The effect, however, might not be as critical as biological viruses on humans.
Technological discoveries in the medical field have made it possible to implant a medical device in a human’s body. These implanted chips are computer programs that can work alongside biological systems.
Research has also revealed that some implanted devices are unprotected against attacks. As such, hackers can reprogram them, negatively affecting the chip and the host.
Are all computer viruses harmful?
With all the noise about computer viruses, it’s safe to think all computer viruses are BAD! However, viruses are just a piece of computer code, similar to instructions.
While certain viruses start with simple intentions, such as causing minor disruptions, many possess more complex and harmful behaviours. All computer viruses are not harmful. Some viruses are harmless; others may delete information. More so, ethical hackers who work for organisations and security outfits engage in the creation of viruses. However, those viruses aim to help achieve a good aim by simulating and assessing the cyber preparedness of organisations.
Protecting Your Computer from Viruses
Protecting your computer from viruses requires a combination of common sense, best practices, and specialised software. Here are some tips for safeguarding your computer:
Use Antivirus Software: Install and regularly update antivirus software to detect and remove viruses from your computer. Ensure your antivirus solution is comprehensive and up to date.
Avoid Suspicious Email Attachments: Be cautious when opening email attachments from unknown sources, as they may contain viruses. Always scan attachments with your antivirus software before opening them.
Avoid Suspicious Websites: Be cautious when visiting websites containing viruses or other types of malware. Use web browser security features to block malicious websites.
Use Strong Passwords: Use strong, unique passwords for all accounts, and avoid using the same password for multiple accounts. This reduces the risk of unauthorised access.
Keep Your Operating System and Software Up to Date: Regularly update your operating system and software to ensure you have the latest security patches and features. This helps protect against newly discovered vulnerabilities.
Following these tips can significantly reduce the risk of virus infections and keep your computer safe.
Tips for Avoiding Computer Viruses
Here are some additional tips for avoiding computer viruses:
Be Cautious When Downloading Software: Only download software from trusted sources, and be cautious when downloading software from unknown sources. Verify the legitimacy of the source before downloading.
Use a Firewall: Enable the firewall on your computer to block unauthorised access. A firewall acts as a barrier between your computer and potential threats from the internet.
Use encryption to protect sensitive data, such as financial or personally identifiable information. This ensures that even if your data is intercepted, it remains unreadable.
Back Up Your Data: To prevent data loss in a virus or other disaster, regularly back up your data using external storage devices or cloud services.
Use a Secure Internet Connection: When using public Wi-Fi networks, protect your data with a secure Internet connection, such as a virtual private network (VPN). A VPN encrypts your internet traffic, making it difficult for hackers to intercept your data.
Adopting these practices can enhance your computer’s security and reduce the likelihood of virus infections. Stay vigilant and proactive in protecting your digital assets.
About Cyphere
We help businesses protect their most prized assets by securing their cybersphere. This includes conducting independent technical security assessments to identify gaps and provide an accurate risk posture to help customers handle their digital risks. Get in touch to discuss your primary security concerns; it includes a free consultation call to advise you without any sales tactics.
