Why Malicious Programs Spread So Quickly?

It seems that nowadays cybercriminals prefer cash to fun. That is why malicious programs of various kinds (viruses, worms, Trojan horses, etc.) are very often aimed at stealing valuable -- in a direct sense of this word -- private and financial information. When written, these programs are spread all over the Web.

What do means of their distribution have in common? Thinking a bit about it will help us ordinary Web users realize how to behave online and what to avoid.

Let's use logic and good old common sense. What do you think are the most suitable (for a criminal)means to spread malicious code? The answer is almost obvious. It is something which, first,ensures his anonymity and, second, offers victims (i.e. us) very little or no protection against malware. Last, but not least -- this means should be very cheap or, even better, free.

(I'll confine myself to mentioning only those means which endanger EVERY Internet user. Not everyone exchanges files or downloads music and freeware. But is there anybody who doesn't send and recieve email or visit websites?)

Well, if you were a cybercriminal who wanted to spread a malicious program quickly and as widely as possible, how would you distribute it?

What first comes to mind? First, sending contaminated emails through spam. It is possible (and not too difficult for, say, a programmer) to enclose virtually anything into the attachment. With more effort, a programmer can create a message without any attachments that will infect a PC anyway.

Though many email service providers offer basic anti-virus protection, they aren't obliged to do it. How effective this protection is -- that's another question.

Besides, spam is very cheap to distribute. Of course, spammers of all stripes don't use their own machines. Why should they? They prefer PCs which became remotely controlled after being infected with a special program. Cybercriminals build huge networks of such machines and hire them out to spammers. Using "bots" (they are also called "zombies" or "slave computers") gives a spammer so valued anonymity -- spam messages come to frustrated PC users from IP addresses registered somewhere on the other side of the globe.

What about other possibilities? websites. Malicious websites are very dangerous.Cybercriminals create them exclusively to execute malicious code on the visitors' computers. Sometimes hackers infect legitimate sites with malicious code.

When unsuspecting users visit malicious sites, various nasty applications are downloaded and executed on their computers. Unfortunately, more and more often these applications contain keyloggers--software programs for stealing information.

Keyloggers, as it is clear from the name of the program, log keystrokes --but that's not all. They capture everything the user is doing -- keystrokes, mouse clicks, files opened and closed, sites visited. A little more sophisticated programs of this kind also capture text from windows and make screenshots (record everything displayed on the screen) -- so the information is captured even if the user doesn't type anything, just opens the views the file.

Blogs can be contaminated with malware, too. In April experts from Websense Security Labs warned users that they discovered hundreds of these "toxic" (contaminated with malcode) blogs set by hackers. Blogs are suitable for them: there are large amounts of free storage space, no identity authentication is required to post, and there is no scan of posted files for viruses, worms, or spyware in most blog