Malware and You – Part 3: Adware

You’re sitting there, surfing along the internet when suddenly a popup comes up, then another, and another. You frantically reboot your computer to get rid of all these popups, but when Windows boots back up, the popups come back too! Congratulations, you’re infected with Adware.

What it is

Adware is technically any type of software that automatically displays unsolicited advertisements on your screen. These advertisements can come in different forms; popups, banners or links attached to your programs, and more. Adware on its own, other than being relatively annoying, is harmless for the most part. However it often comes with spyware or viruses and therefore can be a symptom of a much bigger problem. There is also the problem of the advertisements themselves; they can be misleading or at worst lead to sites loaded with other malicious things like viruses.

Of course there are some legitimate uses of adware out there such as developers using it to support their free software and the like. But the type we’re talking about here is the malware version.

History

Originally, the concept of adware was supposed to be favorable to the people who end up infected with it, the consumers. By using browsing habits and other metrics, the concept was to provide you with advertisements only relevant to what you wanted or needed. By giving you the option to use an “ad supported” version of a program that would normally cost a great deal of money, they could keep their revenue streams strong, while giving you the program for a low price or even free. And on top of it, in theory you’re only seeing advertisements that would interest you.

However, in very little time this semi-annoying but mostly legitimate marketing tool was turned into a new form of malicious software. At first, unscrupulous individuals would create a seemingly legitimate site for an advertisement. Then once their advertisement was approved, they would change that website to send malware and viral payloads to the user. It wasn’t long until flaws and vulnerabilities in Windows XP and it’s web browser Internet Explorer (at the time it was on version 5) were exploited to deliver adware and attached spyware directly to your computer. The adware portion of the packages would display advertisements to sites that were purely scams. Websites would offer things like “Win a free phone” so users would give their personal information freely, hand over their email address, or enter in a credit card. That information would then be harvested for some time before being put to use. Sometimes it would be used to spam your email, or make charges on your personal accounts.

Vectors of infection

These days, adware is much more rare in a malicious format then it used to be, but it certainly still exists. With improvements to the Windows platform and the newer version of Internet Explorer, many of the ways that used to be used to get adware into your system undetected have been patched. But there is always a chance that an infection of this variety will get in.

The most common source of adware though is programs and free downloads such as games and utilities. The best way to avoid it is simply to avoid anything from sources you don’t recognize. Is a utility promising to make your computer run faster for free? Don’t count on it.

Watch here next week when we’ll continue tackling the myths and facts behind malicious software when we talk about one of the most insidious types: Trojans.