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Avast Academy Security Malware What Is Spyware, Who Can Be Attacked, and How to Prevent It

What Is Spyware, Who Can Be Attacked, and How to Prevent It

Spyware can infect any device and give cybercriminals full access to sensitive information such as your passwords, banking details, or your entire digital identity. So what exactly is spyware and what does it do? Read on for a full spyware definition and learn to detect, prevent, and remove the various types of spyware with Avast One.

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What is spyware?

Spyware is a type of malware that tries to keep itself hidden while it secretly records information and tracks your online activities on your computers or mobile devices. It can monitor and copy everything you enter, upload, download, and store. Some strains of spyware are also capable of activating cameras and microphones to watch and listen to you undetected.

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    By definition, spyware is designed to be invisible, which can be one of its most harmful attributes — the longer it goes undetected, the more damage it can cause. It’s like a virtual stalker that follows you through your device usage, collecting your personal data along the way.

    Strictly speaking, there are some valid applications of spyware. For example, your employer might have a security policy that allows them to use software to monitor usage of employee computers and mobile devices. The aim of company spyware is generally either to protect proprietary information or to monitor employee productivity. Parental controls that limit device usage and block adult content are also a form of spyware.

    Chances are you’ll be aware of any benign spyware when it’s on a device you’re using. For the purposes of this article, we’ll focus on malicious spyware; that is, spyware that sneaks its way onto your device without your knowledge, and with ill intent.

    Is spyware a virus?

    Spyware and viruses are both common examples of malicious software (malware), but otherwise, they’re not closely related. The difference between the two lies in their behavior: a computer virus inserts itself into a host program to copy itself and spread through networks of devices; spyware is designed to sit undetected on each device it infects.


    Some types of viruses can bring spyware along for the ride as they spread. But that’s not the only way to contract a nasty spyware infection: you can also pick up all kinds of malware from unsafe websites, suspicious links and email attachments, and infected hardware like USB drives.

    What does spyware do, exactly?

    Spyware can be used to track and record activity on computers and mobile devices. Specific strains have specific behaviors; generally speaking, cyberthieves use spyware to collect data and personal information.

    Once it’s on your computer or mobile device, spyware can carry out a distressing array of covert operations, including:

    • Keylogging (recording everything you type, including usernames, passwords, banking info, etc.)

    • Recording audio and video, and screenshot capture

    • Remote control of the device

    • Capturing content from email, messaging, and social apps

    • Recording and capturing browser history

    Unfortunately, these capabilities have attracted the interest of stalkers and jealous partners; in some circles, spyware is referred to as stalkerware or spouseware. The National Network to End Domestic Violence worked together with Avast to compile some tips to combat spyware and other invasive smart device applications for those struggling in abusive situations and relationships.

    Certain spyware providers market their products as parental control or employee monitoring programs and claim they’re doing their best to discourage consumers from using their products to spy on people. But their advertising tactics and disclaimers are akin to those for massage wands — sure, one can use the product according to the manufacturer’s instructions, but one is more likely using it to achieve goals the manufacturer can’t mention in its marketing materials.

    Types of spyware

    Spyware has uses beyond secretly monitoring and storing its targets’ online activities and capturing sensitive data. Some strains can force unwanted pop-up ads into your internet browsing experience or surreptitiously overtax the processor in your computer or mobile device. Others are used to create traffic for websites. Here’s a roundup of some of the most common varieties of spyware out there.

    • Adware automatically displays advertisements while you’re browsing the internet or using advertising-supported software. In a malware context, adware furtively installs itself on your computer or mobile device, spies on your browsing history, and then serves you intrusive ads.

    • Keyloggers record all the keystrokes you make on your infected device and then save the information in a log file that is typically encrypted. Short for “keystroke logging”, this type of spyware collects everything you type into your computer, smartphone, or tablet, including text messages, emails, usernames, passwords.

    • Infostealers collect information from your computer or mobile systems. Keyloggers are a type of infostealer; other types can do much more than record and store information acquired from your keystrokes. They can also, for instance, scan your computer for specific information and harvest your browsing history, documents, and instant messaging sessions. Some strains can do all their dirty work secretly in one fell swoop before disappearing from their targets’ computers.

    • Red Shell spyware is a type of spyware that installs itself during the installation of certain PC games, then tracks gamers’ online activities. Its makers state they want “to leverage knowledge to help developers make better games” and “make better decisions about the effectiveness of their marketing campaigns.” Red Shell’s detractors oppose the fact that it installs itself without their knowledge or consent.

    • Cookies can be useful; for example, they instantly log you into your favorite websites and serve you advertisements for goods and services that are relevant to your interests. But tracking cookies can be considered spyware as they follow you online as you browse, compile your browsing history, and record login attempts.With the right knowledge and tools, a black hat hacker could use these cookies to recreate your login sessions, so make sure to delete tracking cookies regularly or disable them entirely.

    • Rootkits enable criminals to infiltrate computers and mobile devices and access them at a very deep level. To achieve this, they can exploit security vulnerabilities, use a Trojan horse, or log into a machine as an administrator. Rootkits are typically difficult or impossible to detect, but they can be prevented with strong antivirus software.

    Who is most under threat?

    Criminals use spyware to stealthily collect sensitive information from individuals and businesses. People who rely heavily on online banking are particularly alluring targets for hackers looking to capture financial details to either use themselves or sell to other criminals.

    Businesses need to be especially vigilant against spyware to protect their finances and, perhaps more importantly, to keep a highly effective corporate espionage tool out of their networks.

    There are also high-profile cases of authoritarian governments using spyware to secretly keep tabs on journalists and human rights activists. Furthermore, some companies based in countries like China or Russia, such as Moscow-based Kaspersky, have been labeled a security risk by Western governments due to possible state interference and misuse of their software.

    As with most malware, we’re all one careless click, tap, download, or installation away from falling victim to spyware. Some sophisticated strains of spyware can even infect mobile devices through calling apps such as Skype. One highly advanced variant exploits a vulnerability in WhatsApp that enables it to infect smartphones regardless of whether or not targets answer attacker calls.

    Generally speaking, everyone who uses a computer, smartphone, tablet, or smart device or appliance can become a target of malware. While Windows users are most at risk, spyware has evolved to the point where a growing number of strains are capable of infecting Macs, as well as iOS and Android devices.

    Spyware and mobile devices

    If we take the thriving mobile spyware industry as an indicator, this form of malware is on the rise. The notorious mobile spyware strain called Pegasus has been repeatedly used against politcians, journalists, and activists around the world. And while the developers of “mobile monitoring software” claim their products are for employers and parents, there’s nothing stopping anyone from using them for nefarious purposes. the developers of “mobile monitoring software” claim their products are for employers and parents, there’s nothing stopping anyone from using them for nefarious purposes.

    It’s important to understand that smartphones and tablets, like computers, are vulnerable to a wide array of malware. A consistent increase in usage offers cybercriminals a growing quantity of targets. At the same time, increasingly complex hardware and networks are facilitating the development of new, more powerful malware. On top of this, smartphones offer attackers an additional means of infiltration: text messaging, or SMS.

    You can prevent many mobile threats with antivirus for Android and iPhone antivirus. If you suspect that your smart device has been infected with spyware, we’re here to help:

    How to tell if you have spyware

    We’ve established that spyware is designed to be undetectable and untraceable, making it difficult to tell if you have it. To see whether it has infected your computer or mobile system, keep an eye out for these warning signs:

    • Your device runs slower than normal

    • Your device freezes or crashes frequently

    • You start getting a ton of pop-ups

    • Your browser homepage changes unexpectedly

    • New and/or unidentifiable icons appear in the task bar

    • Web searches redirect you to a different search engine

    • You start getting random error messages when using apps that you’ve never had issues with before

    Of course, these are also symptoms of other malware infections. To determine exactly what you’re dealing with, you’ll need to dig a bit deeper and scan your device with antivirus software that includes a spyware scanner.

    What should I do if my device gets infected?

    Should you discover that spyware has infiltrated any of your devices, be sure to isolate the afflicted hardware, just to be on the safe side in case the attack is virus-based. Once you’ve done this, use a trusted spyware removal tool.

    You may also want to read up on specifics about Windows computer spyware removal.

    Preventing the spread of spyware

    While there isn’t a surefire way to stop spyware itself, you can prevent it from spreading by making sure it doesn’t infiltrate any of your devices. The minimal time and effort you spend doing will save you the headache of removing it.

    Here are a few tips that will help prevent spyware from creeping its way into your digital life:

    1. Use trusted antivirus software with anti-spyware and anti-malware features

    2. Don’t download suspicious-looking email attachments

    3. Don’t click on online pop-ups (or block them entirely with a secure browser)

    4. Don’t open links received in text messages from unknown numbers

    5. Avoid chatting with strangers in messaging apps

    6. Keep your computer and mobile operating systems up-to-date

    Say goodbye to spyware

    Affordable, effective, and nearly undetectable, spyware has become increasingly popular among cybercriminals, making it a huge online threat. Keeping it off your computers and mobile devices doesn’t have to be difficult. Stay aware and stay away from links, attachments, and pop-ups that look suspicious.

    Get ahead of spyware attacks with Avast One, a powerful spyware prevention tool that provides top-notch cybersecurity protection. It’s just one of many reasons why more than 400 million people trust Avast with their security and privacy.

    Protect your Android against spyware with Avast One


    Protect your iPhone against spyware with Avast One

    Patrick Seguin