Viruses, Malware, & Trojans (Oh My!)
With so many types of computer viruses out there, how can we know how to deal with all of them effectively?
First, we must learn the different types of malicious software out there.
Computer viruses are already troubling enough without having to figure out antivirus programs. The programs are called “antivirus” software, but there are so many types of computer viruses: malware, spyware, adware, rootkits, etc. — how do you know if your antivirus software is scanning for and removing these as well? An understanding of the various types of malware out there helps you know the best antivirus solution for you.
Malware Medic is here to help you get a grasp of the nuts and bolts of computer viruses and other malicious types of software. You can read our guide to the best antivirus programs to find out which tools you should trust when your PC’s security is on the line.
Are computer viruses really something the average user needs to worry about? Sure, you aren’t hearing about computer viruses crashing computers on our daily news anymore, but computer viruses are more prevalent than ever. Malicious software of all kinds, including Trojans, malware, and other dangerous viruses are perfectly able to infect your computer, phish your personal data, incorporate your PC into a botnet, and send infected spam messages to all of your contacts.
Seems insurmountable? We agree, it can be daunting. But thankfully, a bit of due diligence can resolve your troubles. All it takes is your common sense, basic understanding of computer viruses, and a solid set of antivirus utilities, and you’ll find keeping your computer secure and free of malicious software is easy!
The Mystery of Malware and other Malicious Programs
We want to keep it simple — first, the difference between viruses and malware. Malware is a more general term, used to describe any kind of malicious code. In fact, the word “Malware” is a short form of the term “malicious software.” Malware represents spyware, adware, nagware, trojans, worms, viruses, and any other code that is designed explicitly to damage your computer or steal your personal information.
What is a Computer Virus?
Malware and computer virus are terms that are commonly used interchangably. However, this is inaccurate. A computer virus is a program that infects a PC, then copies itself from one file to another, and then from one PC to another as files are transferred, sent, or shared.
Viruses commonly infect .exe (executable) files, but may also target your autorun scripts, master boot record, Microsoft Office macros, or what appear to be random files. There are many computer viruses intended to effectively break your PC, deleting and corrupting as many of your files as possible. It’s goal is to wreak havoc throughout your computer system.
An updated antivirus application is important when protecting yourself from computer viruses. It’s also up to you to avoid e-mails that look suspicious or come from unknown sources. Unless someone is supposed to be sending you files, don’t open random attachments.
Look at the filenames of all e-mail attachments — any time you see filenames with the “.exe” extension unexpectedly added to them in your e-mail attachments, there’s a good chance that it’s a virus. Do not open that attachment. It’s especially difficult because not all .exe files are computer viruses, but computer viruses are commonly seen as .exe files. This is why an up-to-date antivirus program is so important.
How does Spyware Work?
Spyware is different from computer viruses. It is exactly what the name suggests — a spy on your computer. Spyware is any malicious software designed to “phish,” that is, steal your personal information without your awareness, and return that information to a central source where it can be used to your detriment — identity theft is no joke.
Spyware can log keyboard strokes to learn your passwords, monitor your search habits, infect your browser with the browser redirect virus, add obnoxious toolbars to your browser, and just plain steal your credit cards and bank information.
The goal of spyware is to make money — your money, to be specific. It will not kill your PC. Most people are using spyware and have no idea they’re running it. Generally, if your computer has one spyware program, there’s a collection of them around. After awhile, you’ll notice your PC running slower . . . and slower.
What makes it complicated is, not every antivirus program is able to detect and remove spyware. It is important that you know the specifications of your antivirus software so you can ensure that you’re protected from spyware also. If your PC is already infected, you should run a combination of MalwareBytes AntiMalware and SuperAntiSpyware to ensure it is squeaky-clean.
Ransomware: Your PC is the hostage.
Ransomware, aka “Scareware” is an awful type of malicious program attack. Users are lured into downloading a fake “antivirus” program. It plays a clever game. Suddenly, you’ll be told that your PC is infected with an alarming amount of viruses…that can only be cleaned if you buy a license from them. This is malware holding your PC hostage, to force you to pay a ransom. Many forms of ransomware will lock you out of the computer, and are not uninstalled easily.
If you discover an unfortunate PC infected with ransomware, there aren’t a whole lot of options. Google the name of the virus and find the specific instructions for how to remove it. The steps are often the same. Run MalwareBytes AntiMalware, SuperAntiSpyware, and if necessary, ComboFix.
Trojan Viruses Create Backdoors
A trojan horse application appears like a normal program, but has hidden, malicious code that follows another objective. Trojans create a secret door into your computer that allows your PC to be controlled remotely. This can be direct control, or your computer could be integrated into a botnet. A botnet is a network of computers that are all infected and usually being controlled from a single hub.
The primary difference between a virus and a trojan is trojans do not copy themselves. They must be installed directly by the user.
A PC infected with a Trojan virus is effectively a pawn. It can be used for various types of cybercrime, including denial-of-service (DoS) attacks, attack concealment, or sending out infected spam all over the globe, including your contact list.
Protecting against trojans is similar to protecting against computer viruses. Keep all your antivirus applications up to date, don’t open strange attachments, and be incredibly careful before you download any pirated software, especially Photoshop. This is one of malware creators’ favorite spots to conceal malicious trojan software.
Worms Take Advantage of Networks
A computer worm will overtake a network to copy itself and send itself to as many other PCs as possible. Powerful worms often take advantage of a security hole to travel from one system to the next, without any obstacles or user awareness. Worms are generally considered the most well-known type of malware, however, a large percentage of users still refer to them as viruses.
A Few Famous Computer Worms
Computer worms have made the news on more than one occasion — the ILOVEYOU worm that attacked computers in 2000 was spread via an e-mail attachment and caused nearly 6 billion dollars in damage.
In 2001, we had the Code Red Worm which spread through a security vulnerability to infect and deface 359,000 websites.
The entire internet was handicapped by the SQL Slammer worm, which exploited a buffer overflow vulnerability and caused a denial of service attack for over 75,000 systems in ten minutes.
Another especially impressive worm was the Blaster Worm which propogated itself across 423,000 systems in the span of 4 days, and forced computers to repeatedly reboot.
However, one unique thing about worms — their exploitation of network vulnerabilities gives us a different approach to preventing them. A strong firewall that is enabled and locked down can help to prevent the spread of worms. But that does not mean you can be lax in other areas. You will still need an up-to-date antivirus program.
That covers the basic types of malicious software that you might encounter throughout your time using computers. A quick review:
– Computer viruses spread by copying themselves across your files, and can delete or corrupt your files.
– Spyware steals your personal information and data, and sends it back to its creator for criminal purposes. It will often appear as normal software and slows down your computer.
– Ransomware will hold your PC for ransom, blocking you from using it until it is removed properly. It disguises itself as an antivirus program and then locks you out of your PC.
– Trojans create a backdoor to your computer for it to be controlled remotely or used in a botnet. Keeping your antivirus program up-to-date is critical to avoiding trojans.
– Worms spread rapidly by exploiting network vulnerabilities and cause denial of service attacks or worse. They can be partially prevented by strong firewalls.
Making sure you have the best antivirus program possible is one thing you can do to ensure you are not vulnerable to the dangers of computer viruses, trojans, ransomware, spyware, worms, and other malware. Thanks for visiting Malware Medic!