Most users I talk to about malware seem to use the following terms interchangeably; malware, virus, trojan, keylogger, worm, backdoor, bot, rootkit, ransomware, adware, spyware, and dialer. Raymond.cc offers some standard definitions to clarify the conversations.
Malware is short for Malicious Software where all the terms above fall into this category because they are all malicious. The different term being used instead of just plain virus is to categorize what the malicious software is capable of doing.
Virus spreads on its own by smuggling its code into application software. The name is in analogy to its biological archetype. Not only does a computer virus spread many times and make the host software unusable, but also runs malicious routines.
Trojan horse/Trojan 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 own purposes. Most of the time, more malware will be installed in your system, 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, 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.
Key loggers 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. Dialers have no effect on ADSL or cable connections, but they are making a comeback with mobile devices and QR codes (I covered Attaging here).
Backdoor / Bots 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 exploit vulnerabilities of a computer program. Whoever attacks your PC will gain control of your PC or at least parts of it.
Spyware is software that spies on you, i.e. collect different user data from your PC without you even noticing.
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.
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.
Rogues / Scareware are also know as “Rogue Anti-Spyware” or “Rogue Anti-Virus”, rogues pretend to be security software. Often, fake warnings are used to make you buy the security software, which the pirates profit from.
Ransomware “Ransom” is just what you think it is. Ransomware will encrypt personal user data or block your entire PC. Once you have paid the “ransom” through an anonymous service, your PC will be unblocked.
There are different categories of malware the author says that most of the malware today combines different kinds of malware to achieve a higher rate of infection and giving more control to the hacker. Most malware is invisible that runs silently without your knowledge to avoid detection except for ransomware and adware.
Using “virus” as a catch-all phrase to include all types of malware is no longer right. The correct word to use should be malware. However, don’t expect the big anti-virus companies to rebrand their products to Kaspersky Anti-Malware or Bitdefender Anti-Malware because doing that may risk losing their brand identity even if they do offer a complete anti-malware solution.
The blog says it doesn’t mean that you’re safe if you don’t see it so it is important to run an anti-virus software from reputable brands such as Kaspersky, ESET, Avast, Avira, AVG (at one time AVG was installing a Yahoo toolbar without notice) MSE together with a second opinion anti-malware such as HitmanPro, Malwarebytes Anti-Malware, and SUPERAntiSpyware. As for Emsisoft Anti-Malware, it comes with its own Anti-Malware engine and Ikarus Anti-Virus Engine.
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- Flashback Trojan affects around 600,000 Macs (macmusings.wordpress.com)
Ralph Bach has been in IT long enough to know better and has blogged from his Bach Seat about IT, careers, and anything else that catches his attention since 2005. You can follow him on LinkedIn, Facebook, and Twitter. Email the Bach Seat here.
Quick Response codes (
Help Net Security writes that when used for legitimate purposes, they make life easier for users. “All you need to ‘visualize such a code is a smartphone with a camera and a QR reader application to scan it – the code can direct you to websites or online videos, send text messages and e-mails, or launch apps,” 
