Difference between Virus, Worm, and Trojan horse

When discussing computer viruses, the most common problem is to refer to a worm or trojan horse as a virus. However, the phrases Trojan, worm, and virus are sometimes interchangeable, and they are not identical. Malicious software like viruses, worms, and trojan horses may damage the computer system. Before diving into the differences between viruses, worms, and Trojan horses, you should be familiar with the term "Malware". Malware is a malicious program that is mainly designed to damage or harm systems. The term "malware" is an abbreviation for "malicious software".

In this article, you will learn about the difference between viruses, worms, and Trojan horses. But before discussing the differences, you must know about viruses, worms, and trojan horses.

What is Virus?

A virus is a computer program that connects to another computer software or program to harm the system. When the legitimate program runs, the virus may execute any function, like deleting a file. The main task of a virus is that when an infected software or program is run, it would first run the virus and then the legitimate program code will run. It may also affect the other programs on the computer system.

After damaging all files on the current user's computer, the virus spreads and sends its code via the network to the users whose e-mail addresses are stored on the current user's computer system. Specific events may also trigger a virus. Several types of viruses include parasitic, polymorphic, stealth, boot sector, memory resident, and metamorphic viruses. Infection with a virus can be avoided by blocking the entry of a virus.

What is Worm?

A worm is a form of a malicious program (virus) that replicates itself as it moves from one system to another and leaves copies of itself in the memory of each system. A worm discovers vulnerability in a computer and spreads like an infection throughout its related network, continuously looking for more holes. E-mail attachments spread the worms from reliable senders. Worms are spread to a user's contacts through an address book and e-mail account.

Some worms reproduce before going dormant, while others cause harm. In such circumstances, the code of the worm's virus is known as the payload.

What is a Trojan horse?

The Trojan horse gets its name from the well-known story of the Trojan War. It is a malicious piece of code with the ability to take control of the system. It is intended to steal, damage, or do some other harmful actions on the computer system. It attempts to deceive the user into loading and running the files on the device. Once it executes, it permits cybercriminals to execute various tasks on the user's system, like modifying data from files, deleting data from files, etc. The trojan horse cannot replicate itself, unlike many viruses or worms.

A Trojan virus spreads by spamming a huge number of users' inboxes with genuine-looking e-mails and attachments. If cybercriminals induce users to download malicious software, it may affect the users' devices. Malicious malware could be hidden in pop-up ads, banner adverts, or website links.

Some well-known Trojan horses' instances are Beast, Back Orifice, Zeus, and The Blackhole Exploit Kit.

Key differences between the Virus, Worm, and Trojan horse

There are various key differences between Viruses, Worms, and Trojan horses. Some of the key differences between Viruses, Worm, and Trojan horses are as follows:

1. Viruses are computer programs that connect to other software or programs to harm the system, whereas worms duplicate themselves to slow down the computer system. On the other hand, rather than replicating, a Trojan horse stores critical data about a computer system or a network.
2. A virus attacks an executable file and attaches itself to it to change the file, whereas a worm attacks system and application flaws. On the other hand, a trojan horse appears to be a beneficial application that contains hidden code that is executed to perform undesirable or harmful operations.
3. A virus's execution and transmission rely on the transfer of infected files, whereas worms replicate without human action and utilize a network to embed themselves in other systems. On the other hand, a trojan horse works as utility software and is executed.
4. A virus could not be remotely controlled. On the other hand, Worms and trojan horses may be remotely controlled.
5. The virus is primarily utilized to modify or erase system data, whereas worms are utilized to excessive using system resources and slow it down. On the other hand, a trojan horse may be utilized to steal user data to obtain access to the user's computer system.
6. Viruses may spread slowly, whereas worms may spread quickly. In contrast, trojan horses may also spread slowly.

Head-to-head comparison between Virus, Worm, and Trojan horse

Here, you will learn the head-to-head comparisons between Viruses, Worms, and Trojan horses. The main differences between Viruses, Worms, and Trojan horses are as follows:

Conclusion

Both viruses and worms damage user documents, files, and other data as they spread from one system to another. However, a virus may replicate within a system after being infected, and it may not spread to other systems without the assistance of a human. On the other hand, worms utilize network weaknesses to spread rather than attaching themselves to the host. In terms of how it is transmitted, a Trojan horse differs from a virus or a worm. A Trojan horse cannot reproduce itself, it should be noted. Users typically download or install them with the main purpose of stealing important data.

Once they have infected the computer system, viruses, worms, and trojan horses are tough to remove, so it is always essential to have a reliable antivirus program and firewall installed on your computer system. As a security precaution, you should only ever download computer applications and apps from reputable and official sources.