What is a Trojan Virus and How can You Defend Against One?

What is a Trojan? A few generations back, you would have heard the history of the wooden horses in the War of Trojans. Now Trojan has come to mean the malicious software that has waged war in the cyberworld. They are so damaging that their existence overshadows the legendary wooden horses that they derive their name from. Our cybersecurity warriors from Perth unravel the facts and how you can protect yourself from Trojans.

What is a Trojan Horse?

A Trojan horse, Trojan virus or just Trojan is malicious software that pretends to be legitimate to trick victims and take control over their device. It is programmed to harm, hinder, steal, or cause damage to your network or device. Though they are sometimes called Trojan virus, it is a misnomer since they cannot replicate like viruses. Trojans act as a delivery vehicle for other malicious software – hence the name. They need the user to execute the program to perform the action for which it is designed.

How does the Trojan work?

• The Trojan virus acts as a legitimate file or attachment through emails or some form of social engineering.
• The user is tricked into downloading or opening the file.
• Opening of the file leads to the installation and execution of the Trojan.

The damages vary since the Trojans act as delivering vessel for other malicious software.

Types of Trojans

Some of the common types of Trojan viruses include:

Backdoor Trojans – are designed to allow the attacker to remotely access and get control of the victim’s computer. They are primarily used for sending, receiving, executing and deleting files at the attacker’s will. Backdoor Trojans are also used to unite a group of infected computers to create a botnet or zombie network to conduct malicious activities.

Rootkit Trojans – are designed to prevent malware detection so that they can stay hidden and cause maximum damage.

Banker Trojans – As the name indicates, these Trojans steal sensitive information used for banking systems and other online transactions.

DDoS Trojans – are designed to execute Distributed Denial of Service (DDoS) attacks. The criminals flood a web address with requests leading to a denial of services.

Remote Access Trojans – are programmed to give the attacker complete control over the victim’s computer through a remote network connection. It is used to spy or steal information.

Downloader Trojans – are programmed to download and install more malware onto the infiltrated device.

Mailfinder Trojans – are designed with the intent to access email addresses from the victim’s computer.

SMS Trojans – They send text messages to premium rate phone numbers from infiltrated mobile devices, causing expenses for the victim.

Signs that your device may be affected by a Trojan

• Unusual system behaviour like programs starting automatically, device setting changing without your knowledge.
• A sudden hike in the number of pop-ups, spams and other interruptions.
• Poor device performance like slowness and crashing from time to time.

If you come across any unfamiliar program, you can try searching online to know if they are recognised Trojans. Recognizing unusual system behaviour and scanning for potential infection are the first steps to protecting yourself from Trojans.

How to protect your device from Trojans

Run computer security check regularly

Scan your computer regularly, which will help you detect malware early on and protect your system from damage. Some programs allow you to set the scanning to run in regular intervals automatically.

Strong and Unique Passwords

Use unique, strong and complicated passwords for each of your accounts. Remember to store them safely.

Always keep your OS updated

Keep your operating system (OS) and other software updated to the latest version. Most cyberattacks take advantage of vulnerabilities in outdated and unsupported software.

Beware of email attachments and links

Avoid downloading suspicious email attachments. Always scan the attachments before opening them. Never click on links unless you are sure it’s from a trusted source.

Install firewalls

Install and enable firewalls to protect your sensitive information.

Avoid unsecure websites

Check for https and the padlock symbol in the URL before proceeding to do anything on a site. Avoid visiting sites that are flagged as suspicious by your security software.

Staying vigilant, being aware of the latest threats, and a sound security system can help protect yourself from Trojans. Speak to our cybersecurity specialists today and let us help your business stay safe and secure. Contact us or email us at cybersecurity@computingaustralia.group.

Jargon Buster

Distributed Denial of Service attack – DDoS – Hackers crash a website or computer by overwhelming the website or server with too many requests or traffic.
Firewalls – is a network security system that observes and manages incoming and outgoing network traffic based on a predetermined set of rules.
Malware – is any malicious software intentionally designed to cause damage to a computer, server or network—Eg. Ransomware, Spyware etc.