Computer viruses, spyware, and other malicious software (malware) are created to damage or infiltrate someone’s computer without their consent. It can be used to gather data about the user, control computer settings, or display unwanted ads. Many of the original malware programs were created as pranks, but today they are often used to further Internet crime. There are now illegal companies that make a profit developing software to initiate forced advertising, send spam emails, or monitor web browsing.
Here are some common forms of malware:
- Viruses – A virus is a destructive kind of computer program that is able to copy itself. They can spread over networks, the Internet, or they can be transmitted to a new computer through removable components like CDs and USB drives. Often, a computer virus will interrupt normal processes on the computer, although they can also exist secretly, with the sole motivation of copying themselves onto as many computers as possible. Viruses are typically attached to an executable file, as they need to be able to execute code.
- Worms – Like viruses, a worm is malicious software that can copy itself and infect new computers. Unlike a virus, it does not require a host program to work. Worms are commonly used to create “backdoor” entrances to computers. A hacker can then use the backdoor to get into the computer and control it. Computers are exposed to worms if there are security issues in the operating system. Companies protect their customers by creating patches that guard against known worms.
- Spyware – Spyware is software that installs on computers, and collects information about the user(s) of that system. It can collect information about web pages that are visited, and record surfing habits. It may also take over browsers to redirect web pages, change Internet connection settings, and interfere with other programs. Spyware is different than viruses and worms as it does not replicate itself and infect other computers. Typically, spyware is installed secretly when the user installs a separate program.
- Adware – This software is designed to download and display advertisements on the computer that it infects. It is sometimes incorporated in spyware programs. The spyware portion determines what types of products or services the user would like, then the adware sends relevant ads.
- Trojans – A Trojan, or Trojan horse, is software that appears to have a valid function, but secretly invades privacy on a computer. Once a Trojan is installed, a hacker can manipulate the computer from a distance. They can search the computer for personal information, and obtain financial information and passwords. They’re also able to download and upload files to and from the computer, or manipulate current files. Trojans are also commonly used to create networks of “zombie” computers that send out spam messages.
There are many systems and programs designed to detect malware, and remove it from your computer. The majority of computers without this protection will have some kind of malware present if it is networked with other computers or connected to the Internet. Such programs are often able to go undetected normally, and can run in the background without you ever knowing. They may not do anything noticeable apart from slowing your computer down.
Here are some ways that you can improve security on your computer:
- Firewalls – A firewall acts as a barrier on a network, analyzing each piece of information that passes to your computer. If an item is suspected or if it doesn’t meet the pre-selected criteria, the firewall blocks it. Good firewall software will block suspicious material that comes in and goes out. It will also be able to automatically detect good software and block obvious malware. A firewall application is a good security tool for any computer.
- Antivirus Software – This software is designed to detect and remove malware from a computer, as well as prevent new infections. This is accomplished by a few different methods. The antivirus software may look for signatures within a file. This is then compared to a dictionary of known virus signatures to determine if it is a threat. The drawback of this is that the signature needs to be created first, so if it is new malware, a virus signature won’t be detected. In that case, the software can analyze the programming code of the suspected file. If it matches known malware code, or is very similar the software will target it. Finally, antivirus software can predict what action a file will execute, and determine whether these are suspicious.
- Passwords – Make your passwords complicated enough that a computer hacker couldn’t guess them easily. Use more than six characters, and incorporate capital letters, numbers, and special characters for increased complexity.
- Online security – Be careful about giving out personal information on websites that aren’t trustworthy. Read the site’s privacy policy if you are unsure.
- Phishing – Watch out for fraudulent emails that pretend to be from real businesses. Make sure that the addresses are real before you give any personal information, like bank account numbers or passwords.