What is a Trojan Virus?

Trojan viruses got their name from the Trojan horse sent into enemy territory with soldiers hidden inside. These soldiers then launched a sneak attack in the middle of the night and helped the Trojans defeat their enemy. A Trojan virus works much like this horse invaded the enemy village. These viruses sneak into someone’s computer and behave maliciously, often without the user noticing.

Is it a Virus? Is it Malware?

From the brief history overview above, you’ll see that the term “Trojan” simply means that there is something hidden within something else. A “Trojan Virus” is simply a virus that is hidden inside of a program that seems to be safe. This is just a sneaky type of malware that will usually hide or remain dormant for quite some time within a program that you trust or don’t believe contains a virus. Unfortunately, there is no telling what exactly a Trojan Virus will do once it is on your system.

Since the term is quite generic, it could be something as benign as just changing your screensaver, or it could be stealing bank login details as you type them into your browser. An important distinction here is that a “Trojan” is simply a method of delivery of something that masks its true contents. However, the term is often used interchangeably with “Trojan Virus”.

So, while a “Trojan” could be a virus, it could also be simply installing “adware” in the background (this makes you see advertisements periodically, even if you are not using the Internet, or it can make all ads you see on the Internet benefit the creator of “adware”, but it does not steal your information). “Adware” is not necessarily criminal, but it is on the “gray market” and does you no good to have it installed on your machine. There are not many times that a “Trojan” can be a good thing for the person receiving it (you). However, the creator of the Trojan will certainly benefit at your expense!

How Do Trojan Viruses Infect Your Computer?

One of the most common sources of this type of virus is through running untrusted executables on your system. These usually fall into one of two categories: something illegal, such as a “crack” for a program (a “crack” is a tool that allows you to illegally use a paid program without purchasing it), or freeware or “shareware”. This is not necessarily doing anything “wrong” or “illegal”, but obtaining free software that is an alternative to common paid software. An easy way to help avoid getting a Trojan Virus on your computer is to not download illegal programs to help you bypass purchasing a program and avoid downloading free software, especially if it comes from a source that you are not familiar with.

There is a third, but less common, way of acquiring a Trojan. This is through a “drive-by download”. This means that when you visit a website, your web browser is exploited, and software is silently installed in the background. Unlike “install wizards” that come with legitimate programs, these will typically run in a way that makes it impossible to tell it is happening. These “drive-by downloads” also fall under two categories. First, it can be on websites that seem shady or might be just a bit “off” to you. For example, websites with “free” adult content are known for doing this. Other examples are pop-up advertisements that may redirect to malicious content and forums used to discuss illegal material like pirated content.

How To Avoid Trojan Viruses

First, never install pirated software or “cracks” for software. Even if they do work, they are illegal in most countries and deprive hard-working programmers of their right to make money from their software.

Next, avoid visiting websites that have “free” adult content. In a lot of cases, you (or your personal information) are the product if you’re receiving anything for free.

Last, always make sure that all your browsers and anti-virus software are updated as often as possible.

How do Trojan Viruses work?

Knowing what threats you’re protecting yourself is vital when it comes to cybersecurity threats. While there are similarities between Trojans, there are many different characteristics and behaviors from one to the next. These similarities help create “heuristics” that anti-virus and anti-malware software use to detect and remove threats. If these programs detect an unusual download or file, they will alert you and allow you to remove the program.

Example of a Trojan Virus

Imagine that someone really wants to get a newly released PC game, but cannot afford to buy it. This person then decides to go to a popular torrent website and download a “crack” that has positive reviews. They then download a trial of the game and then run the crack and it works. The user then plays the game and forgets that they have used a crack to make the game work.

What the user doesn’t know is that the crack includes a virus that logs keystrokes to steal bank details. After a few months, the user logs into his or her online bank account to find that their account has been drained, and all of their money was sent to a foreign country.

Remember, Trojans are a real and harmful threat lurking all over the internet. However, you can prevent them from infecting your computer by following the steps we discussed earlier. Good luck, and stay safe out in cyberspace.