Adware is everywhere on the Internet and in free software programs to display advertisements and collect information. But if this is done without the user's permission, it's a type of malware designed to collect information for hackers.
Adware and spyware
Adware is a common term for software applications or -programs that display advertisements while the program is running. The advertisements may be sent to a user as pop-up advertisements or banners.
Adware programs may also be designed to redirect your searches to advertising websites and collect information about you for marketing purposes so that companies can tailor advertisements to specific types of customers. The same goes for cookies, if you e.g. accept all cookies on a website.
- Adware is therefore not illegal if it asks for your consent and explains what kind of information is collected and how it is used.
However, adware is often used by cyber criminals to collect sensitive information, install other malware and monitor a user's online behaviour without their knowledge.
Cyber criminals can infect adware with viruses that give them access to your computer systems. Adware used for illegal purposes is often used in conjunction with spyware. Spyware is a type of malware that can monitor a user's computer and online behaviour.
The consequences of adware
Spyware, when used in conjunction with adware, can collect information such as passwords, email addresses, IP addresses and websites visited.
In addition, spyware and adware can gain access to a user's webcam and microphone, recording video and audio of the user. The data collected can be sent to third parties who can either use it to carry out cyber attacks or sell it to other cyber criminals. If that happens, a myriad of hackers can get hold of your data and, in the worst case, you lose all rights to it.
Adware and spyware also work together in that the spyware collects personal information that can be used to target advertisements to a specific user. This is also called malvertising and these advertisements can be fake and contain malware that is then downloaded to a user's computer if the user clicks on the advertisement.
How adware programs get installed on your computer
There are two main ways adware can be installed on your computer, mobile or tablet:
Through shareware or freeware
Adware can be part of freeware and shareware programs as a legitimate way to earn advertising revenue that helps fund the development and marketing of the freeware or shareware program. Both freeware and shareware programs are free.
Through malware-infected websites
Both legitimate and fake websites can be infected with malware. Hackers can design websites with malware themselves, or they can install malware in the code of real websites, leading to unauthorised installation of adware when users visit the website. If there are security holes in your browser, hackers can also install viruses through them.
- In rarer cases, adware can be in fake apps or apps designed by a third party that wants to collect information about you. When you download the app to your mobile or tablet, the adware is installed.
Types of adware programs
Offers4U: Offers4U can be helpful when shopping online, but it usually won't help you save money. This type of adware program is used to redirect users to websites through ads. The websites will typically be filled with pop-up advertisements with offers and price comparisons, whose purpose is to get you to buy as much as possible.
- This adware can redirect you to all sorts of sites and you may never know which website it takes you to.
DNS Unlocker: DNS Unlocker uses various techniques to prevent its removal from a system. You can install it to unblock specific websites, but it also sends advertisements to the websites you frequently visit. Clicking on the advertisements can lead to the installation of several types of adware.
Counterflix: Counterflix is an adware that uses marketing campaigns to further distribute itself. Counterflix can be installed through official and legitimate websites or with other programs, where it "attaches" itself to the programs. Counterflix ads can thus lead the user to malicious websites.
Be aware of pop-up advertisements
Like other forms of malware, adware can infect your computer without you noticing. The adware - and malware - can be active for a long time if you do not recognize the characteristics of adware.
Many types of malware, such as Trojans, can cause slow performance, take up space or cause your computer to shut down. This can also happen if the adware programs installed on your computer are poorly programmed.
However, the most common signs of adware are related to advertisements. The signsshould pay most attention to is:
- An increase in the amount of pop-up advertisements or pop-up windows
- An increase in the amount of banner ads
- The appearance of additional programs that you do not install yourself. These are typically other forms of adware or other unwanted software
- Redirection of your internet searches to affiliate websites
How to remove adware
It is possible to remove adware yourself if it has found its way onto your computer or another device:
Automatic method: The best way to remove adware is to use legitimate anti-spyware and anti-adware programs. They scan your computer for adware-infected programs and remove them. There are many versions of such programs, so it's important to research the market properly.
Manual method: Manual adware removal is a slightly demanding task. You need to check all installed programs on your computer and focus on the latest applications. If there are any applications you have not installed yourself, they should be deleted. In addition, it is a good idea to update your computer and restart it afterwards, to "reboot" it so to speak.
Adware can also be installed through fake apps. Therefore, if you suspect that your mobile has been infected with adware, review your apps. It's also a good idea to install antivirus software on your mobile.
Protect yourself from adware
As with other types of malware, it is important to be aware of your behaviour when using your computer and going online.
- Never enter suspicious websites and avoid clicking on banners or windows that suddenly appear.
- Also download other files directly from unknown websites.
- Also make sure you update your devices regularly and use a good antivirus and firewall.
You can also avoid the legal kind of adware. Many free programs, which often contain adware, stop sending you advertisements when you buy the program. Also make sure that any apps you download are approved. When downloading apps and new programmes, it is a good idea to read the terms and conditions, as they should state if adware is included.
This post has been updated on 25-07-2023 by Sofie Meyer.
Sofie Meyer is a copywriter and phishing aficionado here at Moxso. She has a master´s degree in Danish and a great interest in cybercrime, which resulted in a master thesis project on phishing.View all posts by Sofie Meyer