What is a Trojan horse or Trojan?

A trojan horse or trojan is a type of malware that uses social engineering techniques to infect a computer and does malicious activities like stealing sensitive information, formatting disks, corrupting data, degrading system performance, etc.

The name Trojan is derived from the ancient Greek wooden horse that the Greeks used to invade Troy stealthily. Trojan programs generally trick a user by using some form of social engineering and get downloaded and executed into the system. They often misrepresent themselves to appear useful, routine, or interesting to the user and persuade the user to install it.

Unlike worms or viruses, they cannot inject themselves into other files or self-replicate.

What does a trojan do?

If installed with elevated privileges, trojans get unlimited access to the computer and do many destructive activities. These include :

• Data corruption
• Formatting of disks
• Crashing the computer
• Spreading malware to other computers in the network with the help of an infected computer
• Stealing sensitive information, like login information, bank account, credit card information, etc.
• Spying on user activities
• Using infected computers as a botnet and using their computational resources for some illegal activities
• Installing ransomware and extorting money
• Keystroke logging
• Controlling the computer system remotely

Some common types of trojans

Let’s look at a few types of trojans to understand in a better way how they affect us.

Backdoor

This type of trojan gives the attacker remote control over the computer after infecting it. These controls may be data corruption, system crashes, rebooting the computer, displaying attacker-controlled data, etc. Sometimes, attackers even use the infected computers as a botnet and use their resources for criminal purposes. You can find more information on backdoors here: What is a backdoor and how to prevent it?

Exploit

This type of trojan infects a computer and searches for vulnerabilities in the programs or software …