Malware = Malicious software
Classifying malware can be difficult because there are thousands of programs created on a
daily basis and some can be classified into multiple categories. We’ll use the example of a square. A square is also classified as a rectangle because a rectangle has 4 sides. However, a rectangle is not necessarily a square, unless the sides are all equal length. The same idea goes for malware: much of it is a hybrid between different types- but here are the basics.
Programs that appear to be useful, but once downloaded, have malicious program hidden
within. Trojans can do a multitude of things:
Example: Fake anti-virus. Users will see a popup urging you to upgrade anti-virus, or
something similar. Once the users download the fake anti-virus, the malicious
program is downloaded in the background.
Ransomware / Scareware:
Scare tactic malware that threatens a user into paying money. Threats can vary from
encrypting of files, to locking computer, to false reporting to authorities for crimes that users do not actually commit. If the ransom is paid, there is actually no guarantee that the malware will be removed and the damage done will be restored.
Spyware / Adware:
Programs that run in the background and gather information about a person or organization without their knowledge or consent and may send that information to a third party. Adware may come in the form of pop-ups to entice people to click on ads.
Example: Keyloggers are programs that track keystrokes to gain access to accounts, which
would be considered spyware. Adware runs in the background as well to gather information about users’ activities without their consent but uses this information to target ads to users.
They are programs that are spread by inserting copies of themselves into other programs. Virus is a very vague term and not all viruses are created to be harmful but more annoyance. However, viruses can be harmful and destructive and can be used as spyware or ransomware. A virus requires some interaction to infect a computer; like clicking a link or downloading something.
Example: The FBI is an example of both a virus and ransomware. A user is infected through another user when the virus replicates itself and then demands money in exchange to unlock the computer.
Rootkits are software tools that enable an unauthorized user to gain control of a computer system without being detected.
Example: ZeroAccess Rootkit. With this, users cannot access certain programs and can be locked from using the internet.
Worms spread from computer to computer without any human action. A worm takes advantage of file or information transport features on systems, which is what allows it to travel unaided. Worms are a less common malware these days.
Computer repair is needed if any of these malware programs are on your computer.