At the end of 2021, security experts sounded the alarm: The criminal bot network Emotet is active again. Emotet distributes aggressive malware via email. Criminals use this to break into millions of computers around the world, for example to steal bank details or to take networks hostage. How does malware work? And what can you do about it?
What is malware?
Malware is a collective term for various types of malicious software. Malware gets into your computer when, for example, you visit hacked websites, download pirated software, or open a malicious attachment in email. Examples of malware include viruses, ransomware, Trojan horses, and spyware.
An infection of your computer or other digital device with malware can have serious consequences. For example, cybercriminals can steal your banking and login information via malware or find out privacy sensitive information such as your credit card number. Malware allows criminals to disable your antivirus software remotely. Then your computer is no longer protected and malicious programs can enter your computer. This way, for example, your computer can become part of a botnet without you noticing it. This is a network of computers remotely controlled by criminals, for example to spread phishing messages or carry out DDos attacks.
You do not always immediately discover that your computer is infected with malware. You may recognize that your computer may be infected with malware by these signs:
- Your computer just shuts down and you can not start.
- Your computer is running slower than usual.
- Internet speed is slower than usual.
- Programs on your computer no longer work.
- Unwanted programs are automatically installed on your computer.
Types of malware
There are different types of malware. These are the most common:
Adware is a combination of ‘advertising’ and ‘malware’ or advertising malware. Adware shows you unwanted advertising when you visit websites. The most well-known form of adware is the ad pop-up window. Fortunately, adware is only annoying. However, if you’m unlucky, click on a malicious adware ad that is corrupting the security settings of your Wi-Fi network, for example. This makes your network vulnerable and cybercriminals can break into your computer system.
With ransomware, cybercriminals lock your computer files. You can no longer use your files. The criminals threaten to delete your files unless you pay a ransom. Often, they require an amount in cryptocurrency, such as bitcoin.
Ransomware can get into your computer when you open a malicious file, such as an email attachment. Also a leak in your computer due to out of date software allows ransomware to get in. In the latter case, the ransomware arrives on your computer without you clicking on anything. Other terms of ransomware are cryptoware or ransomware.
This type of malware is named after the famous wooden horse. With this, Greek soldiers entered the city of Troy to open the city gates from within. A Trojan Horse is a malicious software program that seems harmless at first glance. This is often sent as an email attachment or hidden in programs you download. The malicious program gives a hacker access to your computer. He can then edit, copy or delete data on your computer’s hard drive, often without you even realizing it.
Spyware is a form of malware that cybercriminals use to spy on you. This allows you to track your activities on the internet unnoticed. For example, cybercriminals steal your passwords and bank details to commit fraud.
A computer virus is a dangerous software program that infects your computer. The virus can copy itself to other files on your computer and then spread to other computers. Distribution is not automatic, but through user actions. For example, when you unsuspectingly send a file that you do not know is infected with the virus. When the recipient opens the infected file, the virus also becomes active on his computer. A virus can wreak havoc on software and files on your computer. For example, when the virus deletes or distributes sensitive data.
A computer worm is a type of malware that infects computers and automatically spreads across your computer network. Unlike a computer virus, a worm does not need to be installed by a user. The worm uses network and operating system vulnerabilities to install malicious software. A computer worm usually arrives via emails, malicious links or an infected USB stick.
Tips against malware
Be one step ahead of cybercriminals and protect your business from malware. You can take these measures:
- Do not download or install illegal software.
- Install antivirus programs, also known as anti-malware.
- Keep your software programs up to date.
- Do not click on links in emails or on sites you do not trust.
- Use an ad filter or ad block.
- Make regular backups of your computer files and keep them in a remote location.