What is a Trojan?

14th February 2025

Trojans make up 58% of all computer malware* – users are constantly under siege.

A Trojan is a type of malware that disguises itself as a legitimate or harmless piece of software, tricking users into installing it, before activating and causing harm to IT systems.

Why are they called Trojans? The name stems from the myth of the Trojan Horse. Supposedly a group of Greek soldiers hid inside a wooden horse, leaving it at the gates of Troy. When the Trojans saw it, they believed it to be a gift and let it through the city gates. At night, the Greeks surprised the Trojans, attacking them from inside the city, capturing it in one swift move.

Trojan malware works in the same way: by appearing as something mundane, like a free game or email attachment, it bypasses security measures and attacks from within. When executed, Trojans can steal data and install additional malware. The types of Trojan include:

·         Backdoor Trojans: allows hackers to remotely control your device.

·         Banking Trojans: designed to steal financial details.

·         Ransomware Trojans: encrypt files and demand a ransom.

·         Spyware Trojans: monitor activity and collect data.

To avoid being impacted by Trojans, you need to be cautious with what you download – you don’t know where malware could be hiding. It is also best practice to have updated systems, an effective antivirus system and a firewall enabled. Ensuring you have the best possible protection in place, you reduce the chance of Trojans infiltrating your system.

If you are infected by Trojan malware there are steps you can take to mitigate the damage and remove the threat:

·         Disconnect from the internet: this prevents the Trojan from communicating with command-and-control servers and spreading further.

·         Enter safe mode: restart your device in safe mode to prevent the Trojan from running while it is removed.

If you need any advice on dealing with Trojans, get in touch HERE, we’d be happy to help.

*https://www.getastra.com/blog/security-audit/malware-statistics/#Malware_Statistics_2023