A Trojan horse is a program that looks legitimate but actually does something malicious. This often involves gaining secret, remote access to a user’s system.
Trojans not only contain malware, they can also work properly together with malware, which means you may be using a program that works as expected, but is working in the background doing unwanted things (more on this below). ).
Unlike viruses, Trojans do not replicate or infect other files, nor do they make copies of themselves like worms do.
It is important to know the difference between a virus, a worm and a Trojan. Because a virus infects legitimate files, if antivirus software detects a virus, that file must be cleaned. Conversely, if the antivirus software detects a worm or Trojan, no legitimate file is involved, so the action should be to delete the file.
It is also important to note that Trojans are commonly called Trojan viruses or Trojan Horse viruses , but as just said, a Trojan is not the same as a virus.
types of trojans
There are several different types of Trojans that can do things like create backdoors in the computer so the hacker can access the system remotely, send non-free texts if it’s a phone that has the Trojan, use the computer as a slave in an attack DDoS, and more.
Some common names for these types of Trojans include Remote Access Trojans (RATs), backdoor Trojans (backdoors), IRC Trojans (IRC bots), and keylogging Trojans.
Many Trojans span multiple types. For example, a Trojan can install a keylogger and a backdoor. IRC Trojans are often combined with backdoors and RATs to create collections of infected computers known as botnets.
However, one thing you probably won’t find in a Trojan is searching your hard drive for personal details. Contextually, that would be a trick for a Trojan. Instead, this is where keylogging functionality most often comes into play: capturing the user’s keystrokes as they type and sending the logs to attackers. Some of these keyloggers can be very sophisticated, targeting only certain websites, for example, and capturing keystrokes related to that particular session.
Trojan Horse Facts
The term Trojan Horse comes from the history of the Trojan War, where the Greeks used a wooden horse disguised as a trophy to enter the city of Troy. In reality, there were men inside waiting to take control of Troy; at night, they let the rest of the Greek forces pass through the city gates.
Trojans are dangerous because they can look like anything that is considered normal and not malicious. Some examples:
- Fake antivirus program: The program displays several windows saying that it found dozens if not hundreds or even thousands of viruses on your computer that you can remove right now if you pay for the program. It could be a small fee that seems manageable or it could be a large sum of money that still seems feasible if doing so removes all these (fake) viruses.
- MP3 Downloader : The tool allows you to download MP3s for free and it really works, but it also works every time, even when you close it, constantly collecting all the keys you type on your bank’s website and sending that information (including your username and password) back to the hacker somewhere remote.
- Screensaver Tool : The program helps you find and install new and fun screensavers on your computer, but it secretly installed the back entry so that when the screensaver has been on for a while (indicating that you are gone), the hacker can enter and have full access to your computer.
How to remove trojans
Most antivirus programs and on-demand virus scanners can also find and remove Trojans. Always-on antivirus tools can detect a Trojan the first time it tries to run, but you can also perform a manual scan to clean your computer of malware.
Some good programs for on-demand scanning include SUPERAntiSpyware and Malwarebytes, while programs like AVG and Avast are ideal when it comes to detecting the Trojan automatically and as quickly as possible.
Be sure to keep your antivirus program up-to-date with the latest definitions and software from the developer, so you can be sure that new Trojans and other malware can be found with the program you’re using.
Check out how to properly scan your computer for malware to learn more about removing Trojans and to find download links to additional tools you can use to scan a computer for malware.