A Trojan horse, or Trojan, is a type of malware that disguises itself as legitimate software or files to infiltrate a system. Trojan horses are one of the most common types of malware – making it crucial to learn what it is and how you can keep your devices safe from becoming infected with Trojans.
Continue reading to learn more about what a Trojan horse is, its distinct differences from a common computer virus, the primary ways in which devices can become infected with Trojans and the measures to take to protect your devices from these threats.
How a Trojan Horse Works
A Trojan horse works by hiding inside files that look innocent, ultimately deceiving the user who downloads or clicks on the file. For example, Trojans can infect your device by you opening malicious email attachments, downloading malicious files, visiting malicious websites or clicking on malicious links. Once a Trojan horse infects your device or system, it can gain access to sensitive data which can be used to steal your identity.
Trojan horses often get mistaken for viruses, but they are not viruses – they are a type of malware. Viruses are also a type of malware, but they work differently than Trojan horses.
How a Trojan Horse Attack Can Happen
There are several common methods by which a Trojan horse attack can happen. Understanding these common ways can aid in safeguarding against Trojan horse attacks.
Downloading malicious email attachments
Downloading malicious email attachments is one of the primary ways a Trojan horse can infect a device. This often begins with a well-crafted phishing email. Attackers impersonate organizations or individuals trusted by the email recipient, making the content and appearance of the phishing email almost indistinguishable from a legitimate email. Phishing emails often contain malicious attachments that appear safe but are designed to infect your devices.
Once the recipient opens these attachments, the Trojan enters the computer without detection and gets installed. After installation, the Trojan can perform various harmful activities. Users need to be vigilant about the emails they receive and be cautious about downloading and opening attachments, especially from unknown or unsolicited sources.
Downloading fake software
One particularly dangerous method of Trojan horse infection involves downloading fake software. Cybercriminals often create fake programs that mimic legitimate software. These programs are so skillfully crafted that it’s hard to tell they are fake, leading users to download and install them.
Avoid downloading software from untrustworthy sources, or software offered by unknown creators, as these are more likely to infect your devices.
Clicking on malicious links
Another common way Trojan horses can infect devices is by users clicking on malicious links. Cybercriminals create links that are designed to be easily clicked by users. These links can be placed in locations frequently visited such as email platforms, social media platforms, online advertisements and even phishing sites that mimic trustworthy websites. Clicking on a malicious link can immediately begin downloading a Trojan horse or other type of malware.
What Kind of Damage Can a Trojan Horse Cause?
A lot of damage can happen if your device gets infected with the Trojan horse malware – your personal information can be leaked, you can fall victim to an account takeover attack, your device can experience performance issues and your financial information can be stolen.
When infected with a Trojan horse, cybercriminals can access the infected computer remotely. This makes it easier to steal confidential data and personal information – placing your personal information at risk of being leaked.
You can experience an account takeover attack
An account takeover attack is when an unauthorized user hacks into one or more of your online accounts and locks you out of it by changing your password. Since Trojan horses gather as much data as possible from your devices, they may be able to gain access to your online accounts if you don’t securely store your login credentials.
When a device is infected with a Trojan horse, it may overheat or become slower. Infected devices may even reboot or crash randomly. This is because Trojan horses excessively consume system resources causing its performance to decrease.
Credit card and internet banking information theft are common consequences of malware infections, especially with types like Trojan horses.
The main purpose of malware is often financial gain, so the financial information stored on infected devices is likely to be targeted.
How To Prevent Trojan Horses and Other Malware
To prevent infection by a Trojan horse and other types of malware, it’s important to follow basic cybersecurity best practices such as the following.
Don’t open unsolicited email attachments
One measure to prevent infection by a Trojan horse is to avoid opening unsolicited email attachments. Infections by Trojans via email usually occur through emails containing unexpected attachments.
Before opening an email attachment, check if the sender is trustworthy. Emails from unknown senders or unfamiliar addresses require particular caution. Even if the email comes from friends, colleagues or other trusted senders, be wary if the attachment is unexpected or doesn’t fit the context of the email.
You can also check the safety of an email attachment by scanning it using antivirus software.
Don’t click unsolicited links or links you’re not sure are safe
To avoid infection by a Trojan horse, it’s very important not to click links on suspicious-looking websites or links that are sent to you unsolicitedly because they could potentially infect your device with malware. Rather than clicking on a link immediately after someone sends it to you, check if it’s safe by safely copying the link and pasting it into Google’s Transparency Report.
Only download apps and software from official sources
An important measure to avoid infection by a Trojan horse is to refrain from downloading software from sources other than official stores. Software downloaded from places other than official app stores or the developer’s website may carry the risk of containing Trojans or other malware.
Stick to downloading from official sources like Apple’s App Store or the Google Play Store.
Invest in antivirus software
Antivirus software is a program you can install on your computer that can detect and remove malware before it’s able to infect your device. Some antivirus software programs also come with the capability to scan email attachments for malware. If malware is detected in an email, the antivirus software removes it from your inbox to prevent you from clicking it.
Keep your device’s Operating System (OS) up to date
As a measure to prevent infection by a Trojan horse and other malware, keep your device’s operating system (OS) and applications up-to-date. These updates contain important security patches that fix known security vulnerabilities. Software updates also provide your devices and applications with new security features and fix bugs to make your devices and applications run smoother.
Enable MFA
Multi-Factor Authentication (MFA) is a security measure that requires additional verification methods when users access their online accounts. As an example, instead of just entering a username and password MFA will require the use of a one-time code sent via email, a TOTP code from an authenticator app or the use of a hardware security key. By setting up MFA, even if your login credentials are somehow leaked, the need for additional authentication establishes an extra line of defense against unauthorized access.
Take Measures to Prevent Trojan Horse Attacks
Taking measures to prevent Trojan horse infections is crucial for maintaining cyber hygiene. Trojans can stealthily infiltrate computer systems, causing damage or stealing personal information, and are particularly dangerous due to their ability to remain undetected by device owners.
To avoid falling victim to Trojans, it’s essential to consistently implement measures against them. Keeper® offers a password manager that helps create and store passwords, allowing users to securely share passwords and files. This protects critical data from unauthorized access and helps both individuals and organizations safeguard against cyber threats like Trojan horses.
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