Malware, a portmanteau of the two words malicious and software, is a piece of dangerous software that is designed to infiltrate and damage a computer system without the owner's informed consent. Many types of malware exist in the wild.
The expression is a general term used by computer professionals to describe applications with a hostile and intrusive nature. Malware can be prevented and in many cases, removed by using antiviruses or other programs used to remove malicious applications. Malicious software as a whole, has caused over hundreds of billions of dollars worth of damage altogether. Despite popular belief, "malware" is generally the universal term for malicious code, and the term virus refers to a subcategory of malware.
See also: worm
A worm is a piece of malware that will spread through multiple services, usually harvesting domains and legitimate contacts to spread itself.
Email Worms are self-explanatory, they are worms that spread through email services. These usually consist of innocent looking emails, telling the user to try out a game or advertising an update for a piece of software. When they are executed, they will execute their payload and repeat the process to another user.
IRC worms are also kind of self-explanatory, they are a sub-category of worms that spread through IRC channels. They are similar to Email Worms as to they provide innocent looking messages with malicious attachments.
A Network worm is a worm that spreads through workgroups, homegroups etc. Infected machines may distribute the malware to other users on the Network.
See also: Virus
Unlike worms, viruses do not spread. The user may download the file mistaking it for another program from a domain or an email. It will then infect the machine and execute the payload. Some are more dangerous than others.
See also: trojan
Unlike other pieces of malware, trojans do not always have bad intentions. Trojans are programs that appear to be legitimate, but either have a major security flaw or are intentionally malicious. Not to be confused with adware. These types of malware is not very common in modern times.
Ransomware is incredibly dangerous. Ransomware can encrypt files, and will force the user to pay money, which is mostly Bitcoin, through online payment transactions for a decryption key. However, sometimes the ransomware does not give the user the real decryption key, and thus, this allows for the hackers to steal credit card information and other personal information. Examples of ransomware is the Cryptolocker virus and the Locky virus. This type of malware is very common in modern times.
See also: Adware
Adware is certainly one of the most common types of malware in modern times. This type of malware is generally downloaded through ads or free programs. They are also distributed through download helpers and sponsored downloaders, such as MediaFire, 4shared, download.com and Softonic. There are also many sub-categories of this type of malware. Some of them can add more advertisements to website the user goes to, and others can redirect the user to other, and most likely malicious, websites.
Fake Software (Rogue Software)
Rogue software is phony software that uses malware and other exploits to get inside your computer. There are many types of fake software, ranging from antiviruses to disk optimizers. After downloading, they often perform a fake 'scan', find many fake objects and offer a price for an activation key. If the user pays this, they will be simply laughed at, as the program will either do nothing, delete itself, or the ones who made the program will commit identity theft. The user would have paid at least $50 or possibly have had all of their money stolen. This type of malware is very common in modern times.
Browser Hijackers are another common piece of adware, often these will install with Sponsored Downloads. They exploit the fact that very few people properly read installers, and often allow programs to set themselves as your homepage, default browser and default search. The simplest way to get rid of these is to run AdwCleaner and reset your browser to its default state. This type of malware is very common nowadays. Scam sites that claim to give away free gift cards may hijack the user's browser.
Sometimes bundled with Browser Hijackers, these often add toolbars to the user's browser's taskbar. Not only are these annoying, they are often intrusive to the user's experience. They cannot be removed easily without Anti-Junkware tools. However, not all toolbars are malicious.
This is found when the user buys a new computer that's cluttered with malware to begin with. These can range from any piece of adware or other malware, often "potentially unwanted applications".
Some manufacturers disgustingly bundle Browser Hijackers such as MyWebSearch with their computers, and charge for removal. The best way to solve OEM bloatware is to either run an anti-junkware tool or format. However, some pieces of bloatware are actually legitimate applications, that probably won't be detected. This type of malware is not that common, and are only usually found when bought from less popular locations.
- Main article: Joke Program
Joke programs are not too deadly to destroy a computer, but can still be an annoyance. An example is Joke:VBS/CDEject.D and Button, a joke program. Only a few are deadly, which includes WinFastener (which deletes a startup file to prevent the computer from booting) and Lose/Lose (which deletes personal files, and if it goes long enough, system files). This type of malware is uncommon in modern times.
Main article: Hacker
Hackers aren't exactly considered malware, but are just as dangerous (if they have bad intentions) as some kinds of malware, as they can insert viruses into the user's computer, damage it via command prompt, or ddos the user. They can also spam the user with other things, or completely corrupt the user's computer. Hackers can also crack passwords in emails, games, bank accounts, and other things.
There are three types of hackers, White Hat, Grey Hat and Black Hat.
White Hat Hackers tend to hack into a website or emails to test security. However, Grey Hat Hackers can do this too.
Grey Hat Hackers are a combo of White Hat Hackers and Black Hat Hackers. They may help or do damage for fun. They can and sometimes will do both for fun and/or money.
Black Hat Hackers are hackers with bad intentions. Some are responsible for viruses, worms and trojans. Examples are: Botnets, Sobig, Melissa and many more like Cryptolocker. These Hackers work for destructive or money-based purposes hoping to destroy and/or scam as many people as possible. These Hackers are notorious in the world for the damage they seek to cause. Some of these hackers would have people pay them to hack people or companies.
This type of issue is quite common in modern times.
Similar to hackers, these are not really malware, but these can also glitch and damage software. This type of issue is usually seen on nearly every program.
- Definition of Malware according to Microsoft
- Malware on Wikipedia
- Computer virus on Wikipedia