Malware has become more and more sophisticated. It has also become harder to detect malware. At the same time, the damage done by malicious software has increased. Protecting your computers against malware is extremely important. Here is a short article explaining what malware is and how you can protect your computer.
First we should sort out what malware really is. A lot of different terms have been used for software that you should not use. The term computer virus has been around for a long time. Computer viruses are one type of malware. Malware is nowadays used as a term describing all kinds of software that you don’t know that have been installed on your computer and which execute harmful operations. The damage done can be limited to just being annoying but criminals have started to use malware in order to steal money as well.
Since malware is a term used for a lot of different kinds of software, it is difficult to protect computers to such a wide variety of attacks. The old computer viruses were relatively easy to stop, they were installed when the user executed an infected executable. Anti-virus programs are good at detecting viruses. But the success of Internet has opened new ways of attacking computers. Old computer viruses were often annoying but not very harmful. Viruses that did too much damage were easy to detect and did not survive for long. Today’s malware can be much more malicious and very difficult to get rid of.
Successful malware must be hard to detect, otherwise it will not get any chance to do its job. But first the malware needs to be installed on the computer. While it is popular to attack computers remotely and try to install malware without the owner being aware of what is happening, most malware is installed by tricking the computer user to install the malware himself. Email is one of the least sophisticated methods but it still works. That’s why most people get official looking emails with attachments supposed to contain important information. But instead the attachment includes malware that the attacker hopes that the user will execute.
A more sophisticated method is phishing. The attacker sets up a website that looks like an official website, such as an Internet banking site, and tries to divert real bank customers to his site instead of the real site. Often phishing emails are used, it is an official looking email with links pointing to the fake website. The victim enters his login details which are saved and then the user is generally told that the login was incorrect and diverted to the real website. Since passwords are typically not displayed on the screen, most people think that they made a typo and try again and this time they log on to the real site. Everything looks normal but the attacker has got the information he wanted.
The old viruses were simple to detect, once the virus creator had released the malicious code, he could not change it. All anti-virus programs needed to know was how the infected code looked like and they could detect it without any problems. But things have changed, nowadays malware creators have learnt to change their code slightly with every infection, known as polymorphism, so it is almost impossible for virus scanners to detect them.
Botnet is a term used for a group of computers that run malware that is controlled by one operator. The computers can be infected with relatively harmless software (for the user), for example used for email spamming or distributed denial of service attacks. But also dangerous software such as keyboard loggers could be installed.
So how can you protect yourself against malware? It is very easy to get infected but common sense, anti-virus software and a firewall will help you. Avoid connecting your computers directly to the Internet, use a basic NAT firewall. They don’t stop all attacks but at least your computers are safe against basic scans and attacks. A real time anti-virus scanner is a must nowadays. They are not fool-proof but they detect most viruses and limit the damage. But most important of all, be careful. Never download things from sites you don’t know. Never execute anything unless you are sure that it comes from a trusted source.
Botnets are a sophisticated malware which are used for financial gains. Here you can learn more about botnets.