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Trojan

A Trojan is a type of malware that disguises itself as legitimate software to deceive users into interacting with it, ultimately stealing credentials or compromising the system.

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About this video

A Trojan, short for Trojan horse, is a category of malware defined by deception. Unlike viruses or worms that spread on their own, a Trojan relies on tricking the user into believing it is something legitimate — a familiar application, a system utility, or a standard login interface. Once active on a machine, it can intercept user input, steal credentials, and create opportunities for deeper system compromise. The name traces back to the Greek myth in which soldiers concealed themselves inside a large wooden horse and had it delivered as a gift to the city of Troy. The Trojans accepted it without suspicion, and under cover of night the hidden soldiers emerged and attacked. The parallel to malware is direct: the threat is disguised as something benign, accepted by the target, and only reveals its true purpose after gaining access. A common real-world example is a fake login screen that visually replicates a program the user already trusts. When the user enters their credentials, the Trojan captures that data and transmits it to an attacker. Because the interaction looks normal to the victim, the compromise can go undetected for an extended period, making Trojans a particularly effective tool for credential theft and unauthorized system access.

What you'll learn

What's covered

Trojan Horse Malware

Key terms

Trojan Horse
Malware disguised as legitimate software that performs malicious actions when executed.
Malware
Software specifically designed to disrupt, damage, or gain unauthorized access to a system.
Social Engineering
A manipulation technique that exploits human psychology to trick individuals into revealing confidential information.
Data Exfiltration
The unauthorized transfer of data from a system to an external destination.
Credential Harvesting
A technique used by attackers to capture usernames and passwords by impersonating a trusted application or login interface.

Topics

Trojan Horse Malware Social Engineering Credential Theft Cybersecurity Threat Analysis

Transcript

Another very prevalent malware that's out there is a Trojan. The key to what makes a Trojan, also known as a Trojan horse, a Trojan malware is that it is intended to mislead the victim. If it gets installed on your computer, it's going to look like something else on your computer.

A good example of this is maybe you have a program that requires a username and password. This is going to pretend to be that program on your computer, and then as you plug in your information, your username and password, it will grab that information and now it has it. So the idea behind a Trojan horse is that it's disguised as something else.

The reason for its name is a mythological story about a Trojan horse. The Trojan horse was a horse that was created by the Greeks. The Greeks hid inside of the horse, and then the horse was delivered to the city of Troy. The city of Troy accepted it as a gift, and then late at night all of these soldiers jumped out and attacked the city. The horse that they used is called the Trojan horse, and it was deceiving to the city: the city thought it was a gift, but instead it was a bunch of soldiers that were attacking the city.

Similarly, a Trojan horse disguises itself as something else, something that's legitimate, gets inside of a computer, and then tricks the end user into submitting information or doing something with this Trojan horse, compromising the system.

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