What is Adware?

Definition

Adware is broadly defined as any software program that displays or downloads advertising material automatically. Depending on the type this can happen at any time after the software is installed, or else when the program is run.

Some adware is legitimate (e.g. shareware programs where the developer is simply trying to recover the cost of making the program, or free trial versions of certain programs that simply display adverts). Other forms also contain spyware and invade the computer user's privacy - these are the ones to be concerned about.

Recently scareware scams have been on the increase - over 200% increase during 2008. These are designed to trick the user into downloading fake security software programs that are actually trojans. The commonest mechanism is to display a popup screen when you visit particular websites that looks like a genuine security alert. It will probably tell you that your computer is infested with viruses or that pornography has been detected and offer to sell you some software to get rid of it. The scareware software is useless in combating security threats. A high percentage of people will fall for the scam and download the software being offered, together with possible adware and spyware. Almost 2% will pay for a licence to activate the software and lose about $40!

Beware of fake security alerts - the only way to ensure 100% protection from digital attacks is to install genuine Internet Security or Antivirus software from one of the major companies.

Operation of Adware

The benign (legitimate) forms of adware may be an annoyance to the user, but cause no harm to data and do not invade privacy by transmitting data to third parties. They are no worse than commercial breaks during TV programmes. In some cases (e.g. where a free version of a program displays adverts) it may be possible to upgrade the program to a fully functional version without adverts by purchasing a licence.

Unfortunately a lot of adware is less than benign and contains spyware as well as displaying adverts. From the hacker's point of view this serves a two-fold purpose. He gets his commission from whatever products are appearing in the adverts while also collecting valuable data about web browsing, shopping habits, bank and credit card details that he can sell on.

Unlike the more subtle forms of spyware, which operate covertly behind the scenes, malicious adware is 'in your face'. You will know almost instantly that something is wrong with your computer, although this can manifest itself in a number of different ways. One possibility is a series of annoying pop-up windows that get in the way while you are trying to do something else with your computer. It is almost impossible not to click on them accidentally. If you inadvertantly (no pun intended!) click on them you will, typically, be directed to a website selling whatever products are being advertised.

Getting Rid of Adware

The benign forms of adware can be simply tolerated (depending on your level of patience!). If they become annoying see if it is possible to buy a licence, or else uninstall the program.

Other forms of adware - the malicious ones which also contain spyware or download it from the Internet - should be treated as malware and eradicated. You may be able to identify the program and uninstall it, but be sure to run a scan with an antivirus program afterwards to clear up any residual effects. Even if you cannot identify the program and uninstall it the scan should still deal with it effectively.

Conclusion

As with viruses and other malware, prevention is far better than cure when it comes to malicious adware. A common-sense approach gives a certain degree of protection, but never 100%. It is essential to install a good antivirus program and keep it up to date with the latest definitions. One that scans incoming emails and Internet traffic in real time is preferrable.

The greatest threat from any malware occurs just after a new application is launched, so not keeping your antivirus program up to date is as bad as not having any antivirus protection at all.

Several vendors offer antivirus programs and many of them also deal with spyware, adware, trojans and other malware. Not all antivirus programs are the same. A lot depends on how much time and effort the vendors put into research and monitoring, also how rapidly they respond to new threats. See the section on Antivirus Programs for reviews, comparisons and recommendations.