There are many different types of malware threats on the Internet, waiting and ready to get downloaded to your Windows PC, to compromise and breach your system’s security. Virus, Trojan, Worm, Adware, Spyware, Rootkit, Malware, Backdoors, PUPs are the most common malware among them. They are forms of unwanted or malicious software.
Different kinds of Malware
This post explains the difference between Virus, Trojan, Worm, Adware, Spyware, Rootkit, Malware, Backdoor, PUPs, Dialer, Ransomware, Exploit, Key loggers, etc. All potentially malicious software explained below is referred to as Malware.
A Virus is a specific way software that is secretly distributed, often by e-mail or instant messaging. They are small software programs that are designed to spread from one computer to another and to interfere with computer operation. A virus might corrupt or delete data on your computer, use your e-mail program to spread itself to other computers, or even erase everything on your hard disk. They are often spread by attachments in e-mail messages or instant messaging messages. They can be disguised as attachments of funny images, greeting cards, or audio and video files. That is why it is essential that you never open e-mail attachments unless you know who it’s from and you are expecting it.
Computer viruses also spread through downloads on the Internet. They can be hidden in illicit software or other files or programs you might download. It can make the host software unusable, but it also runs malicious routines.
To help avoid computer viruses, it’s essential that you keep your computer current with the latest updates and antivirus tools, stay informed about recent threats, run your computer as a standard user (not as administrator), and that you follow basic common-sense rules when you surf the Internet, download files, and open attachments.
Spyware collects information about you without appropriate notice and consent. A computer virus spreads software, usually malicious in nature, from computer to computer. Spyware can get installed on your computer in a number of ways. One way is through a virus. Another way is for it to be secretly downloaded and installed with other software you’ve chosen to install. Spyware is a general term used to describe software that performs certain behaviors, generally without appropriately obtaining your consent first, such as:
- Collecting personal information
- Changing the configuration of your computer
Spyware is often associated with software that displays advertisements (called adware) or software that tracks personal or sensitive information. That does not mean all software that provides ads or tracks your online activities is bad. For example, you might sign up for a free music service, but you “pay” for the service by agreeing to receive targeted ads. If you understand the terms and agree to them, you may have decided that it is a fair tradeoff. You might also agree to let the company track your online activities to determine which ads to show you.
Spyware makes changes to your computer that can be annoying and can cause your computer to slow down or crash. These programs can change your Web browser’s home page or search page, or add additional components to your browser you don’t need or want. They also make it very difficult for you to change your settings back to the way you had them.
The key in all cases is whether or not you or someone who uses your computer must understand what the software will do and have agreed to install the software on your computer. A common trick is to covertly install the software during the installation of other software you want such as a music or video file sharing program. Whenever you install something on your computer, make sure you carefully read all disclosures, including the license agreement and privacy statement. Sometimes the inclusion of unwanted software in a given software installation is documented, but it might appear at the end of a license agreement or privacy statement.
Adware is derived from “advertisement”. Besides the actual function of the software, the user will see advertisements. Adware itself is not dangerous, but tons of displayed adverts are considered a nuisance and thus are detected by good anti-malware solutions.
A Trojan horse is a type of malware disguised as useful software. The aim is that the user executes the Trojan, which gives it full control of your PC and the possibility to use it for its purposes.
Most of the time, more malware will be installed in your systems, such as backdoors or key loggers.
Worms are malicious software that aims at spreading as fast as possible once your PC has been infected.
Unlike viruses, it is not other programs that are used to spread the worms, but storage devices such as USB sticks, or communication media such as e-mail or vulnerabilities in your OS. Their propagation slows down the performance of PCs and networks, or direct malicious routines will be implemented.
Keyloggers log any keyboard input without you even noticing, which enables pirates to get their hands on passwords or other important data such as online banking details.
Dialers are relics from a time when modems or ISDN were still used to go online. They dialed expensive premium-rates numbers and thus caused your telephone bill to reach astronomic amounts,
which meant enormous financial damage to you, the poor victim, who did not even know they were there.
Dialers have no effect on ADSL or cable connections, which is why they are mostly considered extinct nowadays.
A Backdoor is usually a piece of software implemented by the authors themselves that enable access to your PC, or any kind of protected function of a computer program. Backdoors are often installed once Trojans have been executed, so whoever attacks your PC will gain direct access to your PC. The infected PC, also called “bot”, will become part of a Botnet.
Exploits are used to systematically exploitthe vulnerabilities of a computer program. Whoever attacks your PC will gain control of your PC or at least parts of it.
A Rootkit mostly consists of several parts that will grant unauthorized access to your PC. Plus, processes and program parts will be hidden. They can be installed, for instance, through an exploit or a Trojan.
Rogue software pretends to be a security software. Some software scare you into believing thet your PC is compromised or needs optimization – and they push you to buy their software. Often, fake warnings are used to make you purchase the security software, which the pirates profit from. Potentially Unwanted Programs do the same more-or-less. They serve no real function as such.
Ransomware is a type of malware that locks your files, data or the PC itself and extorts money from you in order to provide access. This is a new way for malware writers to ‘collect funds’ for their illegitimate activities on the web.