One of the most annoying problem with computers is when they get infected by viruses or malware. There are several kinds of viruses and they can originate from different actions. Let’s recap the different sources of viruses and see how we can solve them.
Different Types Of Viruses
The words “virus” is too often used as a generic term to cover all types of malicious activity on a computer. The word “malware” (abbreviation of “malicious software”) would actually be more accurate as there are indeed many types of what we generally call viruses, including the following ones.
A virus is a bit of code that sticks to an executable program and then replicates itself to spread to other files. It can cause a wide range of annoying issues from unwanted pop-ups to corrupting and deleting files or even erasing the hard drive.
Scareware & Rogueware
Fake software, also called many names such as fake antivirus, rogue antispyware or else scareware, are malware that scare you into believing that your computer is infected or your system damaged and push you to download a solution software in order to repair a non-existent problem. In the end, installing the fake software will actually launch the infection, usually a worm or a trojan (see below). This type of malware needs your authorisation to spread and often disable your security software, so it will probably not be detected if you scan your computer. Always verify the editor of any software you wish to install on your computer, and do not get lured by pop-ups trying to make you believe your computer is damaged.
Key loggers record whatever keys you press on your computer keyboard and then send the data to a remote location. It does not seem that bad when said this way, but it can have serious consequences when it records usernames, passwords and bank details.
Contrary to Viruses, trojans do not replicate themselves but either try to take control of your PC or steal information from it. They usually cloak under a legitimate program cover until you activate them unwillingly by thinking it is the actual program you wish to use. Sometimes, they are also used to install other malware like keyloggers or rogues.
Like viruses, worms duplicated themselves to infect as many devices as possible, except that they do not need to attach themselves to other programs in order to propagate but rely on networking (emails) or other media (USB drives) for that purpose. This can cause serious network and operating system performance issues as they consume large amount of memory.
A spyware is a malware that collects all kind of information on your computer without your knowledge. If can be as well about your browsing habits as your personal data. It is often installed simultaneously to freeware or shareware applications.
Adware is an abbreviation of “Advertising supported software”. It is a piece of software that displays ads for other software than the one you are using or installing. They mostly appear when installing free software and shareware programs by offering other products or toolbars. They are not very dangerous but mostly annoying and, above all, difficult to uninstall. Some of them also couple with a spyware in order to track your browsing activity.
And Much More!
All the above are the most common types of malware, but there are many more, such as dialers (which are quite obsolete), browser hijackers, rootkits or else randsomware.
Today, most malicious software combine different types of malware in order to achieve a higher rate of infection. In any case, they are most often invisible and run without your knowledge so that they can do as much damage as possible for as long as possible.
Where Do They Come From And How To Avoid them?
Most malware spread through downloads. For this reason, make sure you always download from reliable websites and scan any downloaded files before opening them or installing a new software. Recognising a reliable website is not as easy as one could think. Some websites may look institutional, but are set up by companies to look like they are, when they actually are just for money. For this reason, it is important to be able to make the difference between different types of websites.
Malware spread by pop-up ads always need your permission to install the malicious program that will infect your computer. Do not net yourself get fooled by these pop-ups and trust only your antivirus software to tell you if your computer if infected or not.
Emails And Attachments
Almost everyone knows that attachments are downloads, which makes it obvious that you need to scan them before opening them. But only few people realise that malware can also be spread just by opening a malicious email. If you get one of these, throw it directly in the bin without opening it and create a blacklist that will stop this address to send you more emails.
How Can I Solve Them?
Well, your best bet is to let your antivirus do the work. Sadly not all malware can be resolved by your antivirus software. Still, if you have managed to define what type of malware it is, a few specific antimalware and antivirus tools can help you, like special rogue killer, antivirus boot CD, anti-keylogger software or else spyware removal tools.