You may have heard the term Trojan horse malware from a TV show or movie. The connotations are almost always negative unless the good guy used the Trojan. But what exactly is a Trojan, and what does it have to do with cybersecurity? Let’s find out.
Where does Trojan Horse Malware Get its Name?
You’ve probably come across the Greek mythology story about the Trojan war. Here, the Greeks were unable to penetrate the defenses of the city of Troy. So finally, they came up with a plan. First, they hid inside a giant wooden horse, called a Trojan horse, near the city’s walls. The people of Troy took the horse inside as a gift, unaware that malice was hiding within. Then, at night, the soldiers came out of the horse and opened the gates for their fellow soldiers to invade the city.
Similarly, Trojan horse malware employs deception to invade a target’s computer or device. As a result, it may look like a legitimate program when it’s actually malware. An example of a Trojan is an accounting program that’s hiding ransomware. Such a Trojan may be sent to a business by a threat actor to hijack their systems.
Are Trojans Viruses or Malware? What’s the Difference?
A Trojan is not a virus; it’s malware. The difference between malware and a virus is that a virus is just one type of malware. Viruses destroy data and get in the way of a computer’s normal function. But Trojans are a different type of beast.
What does a Trojan Do?
The similarity between all Trojans is that they use trickery as an infection vector. However, different Trojans can have different functions. Let’s look at some common Trojan classes:
- Backdoor Trojans are pretty dangerous. They open backdoors in a computer for threat actors to access and control them.
- Downloader Trojans can access the Internet and download different malware on a computer.
- Denial of Service (DoS) attack Trojans turns computers and devices into unwilling participants in a DoS attack. Such attacks take down websites and are a menace on the Internet.
- Fake Antivirus Trojans are fraudulent antivirus programs that use scare tactics to force payments from users.
- Infostealer Trojans carry spyware components. They steal your data. Game-thief Trojans and Trojan bankers are info stealers that go after specific information. The latter attacks gaming accounts while the latter targets financial accounts.
- Ransom Trojans carry ransomware components. They lock your computer until you pay a decryption fee.
- Rootkit Trojans can give their authors rootkit access to a computer.
- SMS Trojans hijack devices to send and receive text messages. For example, an SMS Trojan may send your contacts phishing messages.
- Trojan IM targets instant messaging applications to copy login credentials.
How Do I Stop Trojan Malware Attacks?
If you suspect your system has been infected with Trojan horse malware, run a Trojan checker immediately. The software should find and destroy any such unwanted program. Also, be cautious around strange emails, texts, and websites to prevent Trojan attacks. Phishing attacks can help spread Trojans and other malware. Additionally, download the best antivirus software and update your systems with software fixes.
Trojans rely on deception, so don’t be fooled so easily. Apply a healthy level of caution when on the Internet or using your computers or devices.