9 Common Types Of Malware
In this post we will discuss the 9 common types of malware and real world examples for each. The ongoing threat that malware represents significantly impacts both people and businesses on a day-to-day basis. With AV-TEST registering over 450,000 new malicious programs a day the threat is significant and growing.
With so many different types of malware out there it’s no wonder its hard to stay up to date on what malicious programs exist.
What Is Malware?
Before we go over the different types we have to understand just what malware is. Malware is any malicious software designed intentionally to cause damage to a computer, server, client or network.
What Are The Different Types Of Malware?
Below is a list of different types of malware with real-world examples:
1. Ransomware
Ransomware is a type of malware that is just like the name suggests. Its goal is to encrypt files on your machine (holding them ransom) and following this a pop-up will display saying you must pay a sum (usually in bitcoin) to recover the stolen files. One of the most famous examples of ransomware occurred in 2017 and went by the name WannaCry. The malware infected over 200,000 people and companies claiming around 300 USD per user. The estimated damages are said to be close to $4 Billion USD.
2. Viruses
A computer virus is a type of malware that hides within another program. The virus then begins to copy itself and places the copies into other files with the end goal of destroying data. Arguably the most famous computer virus of all time went by the name ILOVEYOU in 2000. The email-based virus overwrote system files and ended up costing the world nearly $15 billion in damages.
3. Spyware
Is a type of software that covertly gathers information without your knowledge or permission. After the data is gathered it then relays it to other parties. An example of a particularly popular spyware was known as CoolWebSearch which would take advantage of internet explorer, modify the settings and send your browser data to the author.
4. Adware
Is a type of malware that displays unwanted advertisements on your screen. Similar to spyware, adware also collects personal information to send you more personalized ads. Fireball is a great example of an Adware that infected over 250 million computers worldwide in 2017. Created by a Chinese digital marketing agency, fireball takes over your browser and installs programs without the user knowing. Following this, the programs lock your homepage and flood your browser with ads.
5. Trojans Horse
A trojan horse is a type of malicious code or software that is used to take over your computer. Just like the “Trojan Horse” in Greek mythology, a trojan is designed to trick you into installing a program that infects your system. Once installed the malware has a number of different functions depending on what the criminal wanted to achieve. A famous trojan horse example is Storm Worm from 2006. Storm Worm started with a captivating headline “230 dead as storm batters Europe”. When clicked the computers would become infected and turn the computers into bots forcing them so spread the virus and send spam mail.
6. Worms
A worm is a standalone program that replicates itself with the goal of spreading to other computers and networks. The host computers will exponentially control and infect more computers in a short time period, disrupting bandwidth and causing other issues. A noteworthy worm is the Morris Worm from 1988. This worm was originally created to gauge the size of the internet but due to a flaw in its design it damaged and bogged down computer systems.
7. Rootkits
A rootkit is a collection of software (usually malicious) that is designed to gain access to a computer or system. Often rootkits are great at concealing themselves and can remain undetected allowing cyber-criminals to access your files and damage your computer. A notable rootkit called Flame in 2012 monitored network traffic and captured screenshots and audio and even had the ability to log your keyboard. The cyber-criminals who created flame were never caught but by the time the rootkit had been discovered it had made it to over 80 servers.
8. Keyloggers
Are a type of malicious software that logs the keys used on a keyboard- without the user knowing. The data mined from this is then retrieved by the cyber-criminal and is used to steal passwords and sensitive information. A famous recent keylogger called Snake Keylogger (discovered Nov 2020) is one of the most prevalent of all time. Often sent through elaborate phishing campaigns the user will open a link and unknowingly install the Snake Keylogger.
9. Bots
Malware bots are programmed to break into computers and networks stealing information and sending spam as well as engaging in other malicious acts. Most often a bot is downloaded and spread through emails and phishing campaigns. Cutwail is a great example of this, and in its prime was sending 51 million emails every minute. Even after multiple law enforcement agencies attempted to take down Cutwail, is still active to this day.