What is spyware, what varieties are there and how to avoid this threat

There are many types of security threats that we can suffer when browsing the Internet. Many types of viruses and malware that can steal data, passwords, cause system malfunctions… In this article we are going to focus on what spyware is . We are going to explain how it works, how they can infect you, what types there are and, of course, what you can do to be protected and not have problems.

How does spyware work?

What is spyware

First of all we are going to explain what exactly is a spyware. We can say that it is malicious software that intends to spy on the victim in some way. It may simply want personal data, seek to steal passwords or see what use you make of that computer.

This type of malware can be in programs that we install, browser extensions, files that we download from the Internet… The problem is that it is not always easy to detect it . Sometimes it goes unnoticed for a long time and that makes it possible for the hacker to act undetected.

Unlike other types of malware and viruses that can affect the operation of the computer more or even encrypt the data, as is the case with ransomware, this time it will not be as visible. It will not cause sudden failures, nor will it cause a system to stop working.

Therefore, we can say that spyware works in such a way that it sneaks into a system and from that moment on it begins to record data and information . It can take a long time before it is eliminated or the attacker has already fulfilled his objective and no longer has any real use.

How can you get infected?

But how can we get infected with spyware? The truth is that the input methods are similar to other varieties of malware. A cyber criminal can use different strategies in order to infect a computer with this type of malicious software, as you will see.

When installing a program

A very common method by which a user can be infected with spyware is when installing a program . That application may be fake, an attacker may have created it simply for the purpose of spying. It is possible either that the software in question works normally or that it does not work at all.

But it can not only be through programs created solely to sneak spyware, but also some legitimate program that has been maliciously modified or through an additional software plug-in.

Virus en máquina virtual

Download a file from the Internet

Another form of spyware entry is to download any file from the Internet . Something similar happens with the programs that we have explained. Perhaps you downloaded a file from a web page and it was placed there solely with the intention of stealing personal information and spying on the victim.

Usually this happens when you download files from unreliable sites. For example, links that come to you through social networks or that you find on the Internet and you really have no guarantee that they are safe. There are many fake pages that they create simply to sneak this type of malware.

For a document by e-mail

You can also end up infected if you download a document that comes attached to an email . Email is one of the tools most used by hackers to achieve their goals and infect victims’ systems. It is a simple, fast medium that can also be sent to anyone.

A simple text file, image, or ZIP folder can contain spyware. They can throw some bait so that the victim falls and opens it. For example, saying that it is a prize, that they need to verify some information, that it is an unpaid invoice, etc. All this can make the user who receives that email end up clicking.

software vulnerabilities

But do not forget the possibility that attackers take advantage of any vulnerability that exists. These security flaws can affect the operating system itself, but also any program that we use. For example, the browser itself and spyware sneaking into Chrome or Firefox.

Uncorrected vulnerabilities are behind many cyber attacks. It is, without a doubt, an entry route that is widely used by attackers, and not only in the specific case of spyware, but also in many other threats that exist on the Internet.

What types of spyware are there

After explaining what spyware is and how it can infect us, we are going to talk about what types there are . Not all of them have the same objective, although all of them are going to spy on us in some way and collect personal information that they can later use for bad purposes.


We can say that it is one of the most common varieties of spyware. This malware is usually in browsers and basically what it does is steal information to send deceptive advertising. They are the typical pop-up windows that appear constantly when browsing, when we visit a web page.

Normally, clicking on those windows tends to aggravate the problem. This is when they can sneak malware or serve to send information to attackers. It can also happen that you install an application and that it contains adware and through it it can spy on you and know what you do.

web crawlers

In this case, the spyware will be specifically responsible for tracking your Internet browsing . It can collect what you search for on the web, what pages you visit or what you install in the browser. They can simply use this data to sell it to third parties for profit, but also to launch other attacks.

By collecting data of this type they can know what you are looking for on the Internet, what services you use, etc. This allows an attacker to launch personalized Phishing attacks, which can be more successful and can steal passwords or take control of the computer without the victim realizing it.


But spyware can also be used to steal passwords directly. It is what is known as a keylogger. It is a software created to record the keystrokes that the victim makes. A way to steal usernames and passwords without the victim knowing.

Keyloggers can arrive by different methods, but they are usually by downloading some insecure program or through a file that we download from the e-mail. However, whatever the route of entry, the objective will be to steal passwords and be able to take control of a device.

keyloggers en paginas web


Yet another variety of spyware is what is known as infostealer. It is a bit of a mix of keylogger and tracker. The objective in this case is to spy and collect all kinds of personal data , from the system, from the use that the victim makes of a computer. All of that is going to be stolen by the attacker or received in a database.

With this information it could carry out other attacks, sell it to third parties, etc. It is used to, for example, spy on a company and get information that they can sell to the competition. It is a type of malware that puts the victim’s privacy at serious risk.

How to be protected

What can you do to be protected from spyware? It is important that you take measures both to prevent, and also to solve the problem in case you have already been a victim. We are going to give you some interesting tips that you can put into practice on any device.

Use security software

The first thing you should do is use good security programs. This will serve to prevent the entry of spyware, but also to eliminate it in case you have already been a victim of this problem. There are many options available, both free and paid, to protect computers.

A good antivirus is Windows Defender itself. It comes integrated with Microsoft systems and works fine. However, there are other alternatives such as Avast or Bitdefender that will also help you with this task.

keep everything up to date

Of course, it is essential to have everything correctly updated. Spyware can come in through unpatched vulnerabilities. They can be bugs that affect the operating system itself, but also the browsers you use, such as Chrome or Firefox.

To update Windows you have to go to Start, enter Settings and go to Windows Update . Possible updates will appear there and you must install them all. This will help optimize performance, but also fix those security issues that can be the gateway to cyber attacks.

Actualizar Windows 11

In the case of Chrome, you can update it if you go to the top right menu, click on Help and enter Google Chrome Information . It will automatically start installing a new version, if one is available. It is something that will help prevent you from being spied on by the browser.

Actualizar Google Chrome

Download only from trusted sites

Another thing to keep in mind is to only download from trusted sites. If you are going to install a program, you should always do it from its official website or through secure application stores, such as Google Play or the Windows Store. This will prevent you from installing software that may have been maliciously modified.

You should also download files and documents only from trusted sources. You should take a good look at the URL where you are, the appearance of that site and look for information on the Internet in case you have doubts about whether or not that website is really trustworthy.

Common sense

But if there is one important thing to avoid spyware, it is common sense. You must avoid by all means making mistakes that could leave you exposed on the Internet. For example, do not download files that arrive by email and you do not really know who may have sent it.

Keep in mind that most cyber attacks, and that also includes the different varieties of spyware, will require the victim to make a mistake. That would give attackers a free pass and they could steal information or sneak some type of malicious file.

In short, as you have seen, spyware is a major problem that affects the privacy and security of users. There are different types and they can also be reached through various methods. It is essential at all times to be protected and not make mistakes.