What is it?

A Potentially Unwanted Program, or PUP for short, is a program that may be unwanted, despite the fact that a user consented to download it. Some examples of PUPs include: spyware, adware, or additional web browser toolbars, and they are often downloaded in conjunction with a program that the user actually wants.

Our Experts Explain

The term, Potentially Unwanted Program, was coined by McAfee, the global computer security software company, when marketing companies started objecting to the fact that their products were being classified as “spyware”, even though all of the relevant information for informed consent was included in the product’s download agreement. Users, however, rarely read through the entire download agreement before ticking the “I Agree” box.

PUPs rarely do anything useful. For instance, browser toolbars just clutter your screen, track your browsing, pop-up additional advertising and mostly just slow your computer down.

The Difference between PUPs and Malware

The main difference is the method in which the software is distributed. Malware is malicious software that is installed without your permission. PUPs are programs that piggy back onto an End User Licence Agreement (EULA) and trick you into installing them.

The distribution of PUPs tagging along with free software downloads is a lucrative market. And it is all completely legal, because you have accepted some fine print and given your permission for the company to run the PUP program on your computer.

Antivirus companies have to be very careful as to how they flag this unwanted software in their scanning results, as there have been a few lawsuits brought against AV companies in the past because they classified them as Malware. By labelling them “Potentially Unwanted Programs” instead, the AV Companies are protecting themselves from legal action, however, they are still providing useful information to their customers about programs they may not want on their computers.

Note: Most Anti-virus software differentiates PUPs from other types of malware, such as viruses, Trojans, and worms, which can be safely assumed to be unwanted by the user.

Not all Antivirus Software will detect PUPs, however companies like Malwarebytes, provide a list of criteria, that they use to classify a software program as a PUP. Features such as: hidden close options, obstructive ad content, pop-up windows, browser redirections to a competitors’ websites, etc…, will all cause a program to be flagged as a PUP. While not illegal, they are all very frustrating features when you are simply trying to use your computer.

Avoiding PUPs

The best course of action is to remove any PUPs from your computer. Or better yet, avoid installing them in the first place. Always pay attention when installing any software and NEVER choose the recommended “Standard Installation” or “Quick” installation option. ALWAYS choose the “Custom Installation” option, because that is where you will find the tick boxes that allow you to stop the PUPs from installing.

82_pup-visual-insideFigure 1: Example of a PUP

In the above example, if you select the “recommended” installation, as well as some free DVD converting software, you will also have a new AVG Toolbar on your web browser, a new homepage, defaulted to AVG Secure Search, and also every new tab you open, will default to the AVG search page. By choosing a custom installation, you have the option of turning those additional installations and features off.