A malware or "malicious software" is a program developed with the purpose of harming a computer system. There are several methods used by hackers to infect a computer such as phishing for example.

Types of malware


Ransomware (or ransomware in French) is malicious software that will block access to the computer or your files.


Spyware is a program designed to collect information from a device or network. This data will be transmitted to the hacker for fraud or identity theft purposes (personal data, login information, credit card numbers).


The role of adware is to force the infected computer to display advertisements. These displayed advertisements help generate revenue for the adware creator.


A rootkit is a series of tools that, once installed, will allow the hacker to perform various tasks: capture passwords, steal banking information, DDos attack, disable security software. The rootkit provides the cybercriminal with administrative rights over the infected system.


Like a virus that can infect a person, this IT virus is a piece of contagious code that infects software and spreads from file to file on a system. When infected software or files are shared between computers, the virus then spreads to the new host.


Worms are a type of malware similar to viruses, which repeat themselves in order to infect other computers on a network and usually cause damage by destroying data and files.

Trojan horses

A Trojan horse is one of the most dangerous types of malware. It usually masquerades as something you might be interested in in order to trick you. Once on your system, the Trojan horse creators gain unauthorized access to the infected computer. From there, Trojans can be used to steal financial information or install threats such as viruses and ransomware.


This is a form of malware that, once installed, will use the resources of the infected machine to mine a cryptocurrency such as Bitcoin or Monero.

How do I know if my device has been infected?

Here are some symptoms to watch for on your device:

How to remove malware?

Depending on the type of malware, there are free or paid tools to eradicate it. Depending on the nature of the malware, a somewhat robust antivirus will be able to do the job. In other cases, you will need to use specialized tools.

How do I protect myself against malware?

Here are some ideas: