“Malware” is the common term to describe a malicious program/infection within a computer system. These might include: viruses, computer worms, Trojans, spyware, adware, rootkits, browser hijackers, rouge security software, ransomware etc. Most often it occurs in a form of code or script. This kind of software disturbs computer activity, might gather sensitive info (in case of spyware/adware/ransomware) o gain a remote access to it.
Hence the name – a malware that demands ransom. It does so by denying access to the computer by the user, thus asking for a ransom to be paid in order to “unlock” the system. It might just lock the access to the shell, but it also could do a more harmful job by encrypting the user’s files (cryptolocker). Most often this kind of malware acts in a manner of a trojan horse – getting access to the system by a downloaded file, e-mail attachment or a unsafe network.
Another malware that has description within its name. It is a piece of software that disguises itself and appears to be as legit security tool. Normally it generates misleading alerts, scaring the user into thinking that he or she has a computer full of malicious acting fimes/software/. Most often the scan by these “programs” is free, but the fix of the “infection” is paid – it redirects the user to a hoax website in order to purchase the full version of the software, thus stealing the users’ sensitive bank/identity data.
As the name suggests spyware is a piece of software that is used in order to spy/gather sensitive data of the user without his or hers consent. Spyware software is often installed without the knowledge of the user. Most often these malwares act as a trojan as trojans are a Remote Administration Tools, thus a covert investigation is possible. Data gathered is most often sold in a black market for cybercriminals/advertisers etc.
A piece of software, that benefits its author, based on advertising purposes. This kind of software might analyze users’ behavior on the internet in order to fit the interests of the consumer. Often this is considered a malware as the ads (and the installation of the software itseld) might be displayed without a users consent.
Is a piece of software that hijacks the users browser(s). Upon installation the user might not be notified as these malwares are often bundled and the common user selects a ‘quick’ installation process. Thus the browser options are changed: the default search engine, the home page, the new tab page etc. Often the hijacking is used for advertising purposes to benefit the creator (also the creators might lease there hijackers for companies who’d like to advertise)
Potentially Unwanted Application:
Is a program that might be undesired by the user, but despite the fact installs itself upon the system as it is often bundled (similarly to browser hijackers) with a desired application. These might include a toolbar, coupons, ad pop ups etc.