Malware is a malicious code with the intent to damage the system it is downloaded onto. Malware comes in various types. The most familiar of those are as follows:
Trojan horse
This is a malicious code, generally exchanged through email, which displays itself as a useful program but has a hidden agenda. One instance is the Zlob Trojan, 2005/06. This would copy itself, create changes to directories, etc. Waterfalls screen saver Trojan horse, claims to be a screen saver, but unloads viruses and scripts while running. To avoid this attack allow the file to be scanned before executing it, as malicious scripts will be recognized.
Virus
A virus is a malicious code that replicates itself onto other programs and users through email and other various routes. It then causes problems for any user or program it becomes associated with. ACTS. Spaceflash is a known virus from 2006. This virus was in MySpace “about me” pages and would target anyone who accessed an already infected “about me” page. The virus would then erase the new user’s page and replace it with html code. A common way to receive a virus, one that replicates itself through computer memory, is by opening an email attachment. Good common sense and a virus scan package are the best ways to deter viruses.
Logic bomb
This is a malicious code that is hidden and set go to work when a preset determination has been met. A logic bomb was executed to manipulate stock prices by a disgruntled employee. This seems to be a popular reason to use a logic bomb. The answer may be to treat your employees’ right, while keeping an eye out for disgruntled employees. In 2006 an administrator at USB PaineWebber was jailed for planting a logic bomb that would delete files on a certain day. The administrator bought stock and predicted what would happen to the company (due to his bombs).
Worm
A worm is a program that makes its way through the system without the user doing anything. The Morris worm shut down the internet for days. The Morris worm gained unauthorized access to computers. It caused a buffer overflow so people could not access their internet back in 1988. Types of worms now are similar to email viruses and common sense should be used when opening files.
Applet
An Applet is a program that can be useful but can cause problems for other programs on the system. An example of an applet malware is receiving an automated applet download when visiting a website. JavaScript is triggered and may run malicious scripts. There is a Java security model that requires java to run in a restricted environment to control malicious content.
Most Anti-Virus programs have removals for certain malware. One can go to some Anti-Virus sites to scan their system and download a removal tool to rid the system of the malware.