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Trojans: Understanding Their Behaviour and Characteristics

Trojans come attached to what seems like a legitimate piece of software, before infecting your computer. Watch Skylar Simmons explain more.
In this section, we’re going to talk about Trojans. And this first video, we’re going to be talking about Trojans, their capabilities or behaviours, and their operations. So what is a Trojan? This is pretty much like everything else we see. It’s a piece of malware that attempts to disguise itself as a legitimate application. One of the things that started to set Trojans aside, and where things start to get a little bit more convoluted, is when we look at viruses and worms. Viruses embed themselves into legitimate applications. They put those hooks in and when you run that application or you run that file, that’s how you get infected.
Worms can do a similar thing and then they can start self-replicating across the network by using things that are in place. Trojans really act as a dropper a lot of times. They’re basically a wrapper to get another piece of malware or onto a system. When we think about it, Trojans in and of themselves probably don’t do any malicious activity outside of dropping another piece of code onto your system. And these are commonly seen embedded in Microsoft Office documents. We talked about macros and stuff like that a little bit before and we’re going to look at that here in a minute. But you would get a Microsoft office document, or a PDF, or something like that.
And inside of that it would have a piece of malicious code that would execute. And that would be what a Trojan is. And then maybe it’s very obvious or maybe it’s not, but Trojan’s named after the Trojan horse from the Iliad. The Greeks assaulted Troy for many years during the war. They were never able to defeat Troy and eventually one night they came up with this idea that they would hide a bunch of forces inside of a wooden horse. They’d leave it at the gates of the city and when it was brought in as a gift, the soldiers come out in the night and opened the gates.
So that’s kind of the idea here, that you take something that looks benign, you hide something malicious in it. And once it’s in place you use it then to actually establish a bigger and more dangerous threat. In the next video, we’re going to talk about a Trojan from the early 2000s called Beast. And it was a pretty significant Trojan because of its capabilities. It was the first time I’d really seen something do what this did.

In the video, you will learn about Trojans, which take their name from the ancient Greek legend of the Odyssey.

During the 10-year long Trojan War, the Greeks offered the gift of a massive wooden horse to the Trojan army and pretended to sail away. As the horse was a symbol of the city of Troy, the Trojans believed it to be a peace offering, but hidden inside was a selection of men from the Greek army. The Trojans let the horse inside, where the troops emerged and sieged the city.

Like its namesake from the myth, Trojans come attached to what seems like a legitimate piece of software, before infecting your computer.

Over to you: How do trojans differ from worms? Share your thoughts below.

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Cyber Security Foundations: Common Malware Attacks and Defense Strategies

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