It was a tough choice to choose a title for this post. I also considered “It ain’t necessarily so” for a title.

This blog is aimed at our less technical users, but perhaps more technical users will find it useful as a teaching aid as well. Today I am going to teach you how to write a very simple program to demonstrate that computers lie each time they are instructed to. Believe it or not, you can write a very simple visual basic script program and I will show you how.

First open up notepad. Next type the following line into notepad.

Msgbox “Your Computer has 5,000,000 Viruses on it. Buy Antivirus Whiz to clean them all up”

No fair copying and pasting, you are supposed to write your program! Now, save the file on your desktop or somewhere that you know how to find. Name the file something like “Liar.vbs” (without the quote marks.

OK, if you are running Windows XP or Vista you can just double click on the file. For Windows 7 you need to right click on the file, then choose “Open with” and then use the Microsoft Windows Based Script host.

On Windows 7 you will get a warning message, and in this case choose open and you will see a message box that says your computer is infected.

See how easy it is to make a message box? On the web, scripts are in virtually every webpage and they generally run without interaction. In most cases JavaScript and not VBS will be used, but it is quick and easy for me to demonstrate the concept here with VBS. You might notice that this message box does not have a title. We can fix that quite easily. Change your VBS file to look like this. Don’t add a carriage return, this is all on one line. Do note that the two commas between the sentences are required, as are the quote marks. Don't forget to save the file first!

Msgbox "Your Computer has 5,000,000 Viruses on it. Buy Antivirus Whiz to clean them all up",, "The Windows Security Center wants you to know..."

Wow, a Windows Security Center warning? No, you programmed your computer to lie, so it did. Anyone can program your computer to lie if they get you to run their programs. Let’s try one more thing. Change your VBS file to the following and save it:

Msgbox "Your Computer has 5,000,000 Viruses on it. Buy Antivirus Whiz to clean them all up",20, "The Windows Security Center wants you to know..."

Notice, I put the number 20 between the commas. This tells the computer to show the message box with a critical notice icon and the buttons “Yes and No”

So, what will happen if you click the buttons? Right now they all simply close the message box because there is no further programming to specify what happens. All of the buttons can be programmed to do exactly the same thing. I could make the Yes button take you to an ordering webpage and I could make the No button do the same thing. If I put up a Cancel button I could make it do the same thing. The titles on the buttons are only labels and do not control what happens when you click on them. It is up to the programmer to make them behave appropriately. In the case of fake AV, the programmers do not program the No or the Cancel buttons to do what you want them to do.

See how simple it is to get a computer to lie? Remember when you visit a web page and a message comes up, just because it says it is a Windows System warning or something else that looks official, it ain’t necessarily so. Skilled programmers can make these things look very convincing. If you land on a webpage and it says it is scanning your computer the best thing you can do is open up the task manager and end the browser application or process.

Randy Abrams
Director of Technical Education
ESET LLC