What is Malvertising and How Can I Protect Myself Against Malvertising?

Did you know that you can be a victim of malvertising while browsing on a legitimate site? Wondering what could be the consequences of it? Let’s have a look at malwertising and how can I protect myself against it.

Well, let me tell you that malvertising involves inserting malware or malicious code into legitimate online advertising networks or webpages. The target websites are usually renowned or legitimate websites that users frequently visit like Spotify, The New York Times, etc.

However, malvertising is not the same as ad malware. Malvertising consists of injecting a malicious code on the web publisher’s page and impacts all who visit the webpage. Adware or malware is installed on a user’s system without their knowledge and is hence highly targeted.

What happens in a malvertising attack?

An online advertising channel is a complex network of publisher sites, ad exchanges, ad servers, retargeting networks, and content delivery networks. There is a lot of to and fro between servers when someone clicks on an ad. So, attackers target an imperceptible point in this complex network to inject a malicious code in it. The ultimate attack can happen in two ways:

Pre-Click malvertising attack:

There is a possibility of being attacked even without clicking a malvertisement. Do you know how? Well, even when you simply visit the site containing malvertisement or view it without specifically clicking on it, then the following can happen:

Forced redirection – The browser is re-routed to a malicious website automatically even if you don’t click on the ad. This is often seen happening in streaming websites.

Displaying unwanted ads – Executed with the help of Javascript, it leads to the display of unwanted ads, malicious content, and pop-ups.

Post-Click malvertising attack :

Clicking on a malicious ad may lead to the following scenarios:

Installation of malware on the user’s system.

This is usually achieved by the process called “drive-by download.” It refers to the auto-installation of malware on the user’s computer.

Redirection to a malicious webpage.
Redirection to a malicious website similar to the original site, which consequently leads to a phishing attack to extract valuable private information from the user.

Types of malware that malvertising can expose you to:

Adware;
Ransomware;
Botnets;
Banking Trojans;
Cryptojackers.

How can I protect myself from malvertising attacks?

Use ad blockers to block all ads.
Use an all-round antivirus software to prevent auto-download of malware.
Avoid using Flash and Java that are vulnerable points of malvertisement attacks.
Update browsers and plugins to prevent malvertising attacks.

Therefore, hoping that you can employ the recommended methods to safeguard yourself against malvertisement attacks.

Adrian