WHAT IS TROJAN HORSE VIRUS?- 15 TYPES OF TROJAN YOU SHOULD AWARE

 

What is Trojan Horse Virus?

It is not what you think, that disguised Trojan Horse, from Greek mythology, that resulted in the fall of the great city of Troy. In the digital world, a Trojan Horse Virus or Trojan is a kind of malware that is frequently masked as a real program, software, or application. On the surface, these malicious codes, applications, or software may look legitimate but can take control of your sensitive data, system, or network.

Users are usually tricked by some attractive offer pop-ups in their windows or attractive campaign ads and by clicking them, they are redirected to some malicious websites or download free applications or games. In the background, these websites or applications will damage, disrupt, or transfer your data to cybercriminals and compromise your system or network.

Trojan Horse or Trojan Horse viruses do not only affect laptops or desktops, they can also inflict smart devices including smartphones, tablets, gears, etc. In the case of the Trojans of mobile devices, they look like almost authentic applications but in reality, they are nothing but the fake version of the original apps armed with different types of malware. 

Though it is almost impossible to place these types of apps in the authentic app markets, they are available on the websites and in the unofficial app markets. There are specific types of Trojan malware designed to attack only android devices. This type of malware can pass the information to cybercriminals without the users’ consent. Users’ mobile security can be compromised, which will lead them to take control of their home routers or office routers. After taking control of the data traffic, cybercriminals can redirect the traffic and commit crimes anonymously.

Let’s take a look at the most dangerous Trojan Horse Viruses and how they operate:

1. Backdoor-Trojan: Backdoor is that type of Trojan virus that allows a cyber attacker to create a backdoor that would eventually let the attacker access the infected system remotely from anywhere. With a Trojan backdoor malicious program, an attacker gains unauthorized access to a system by leveraging the security and system flaws. This kind of Trojan usually remains hidden in the background and it is very hard to detect.
2. Rootkit-Trojan: Trojan rootkit is a type of Trojan that does the installation and execution of codes that are programmed to help the attacker to gain silent authorization to a system or framework without informing or taking any permission of the user. There are various types of Rootkit virus such as Bootkits, Firmware Rootkits, and Kernel-Level Rootkits.
   
3. Downloader-Trojan: Trojan downloader is a type of Trojan virus that downloads and executes unwanted, malicious programs or applications including Trojans and adware. The primary objective of these executions is to acquire additional pieces of malware from the internet in the attacked computer. 
   
4. Banker-Trojan: Banker is that type of malware program that is crafted to exploit the financial data of the user. Generally, Trojan-bankers exploit the banking systems, payment methods like credit cards. After extracting data, it transfers these confidential data to the attacker who has deployed the Trojan. 
   
5. Ransomware-Trojan: Trojan ransomware is embedded in malicious email attachments or software. After installing or opening the file or application, it blocks the user from accessing his system or specific data like documents, pictures, or all folders in the system, etc. The user can access the corrupted resources only by fulfilling the demand of the attacker, usually, by paying the attacker via online payments or paying in bitcoins, etc. 
   The most dangerous Trojan ransomware is CryptoLocker, Petya, Locky, WannaCry, and Cerber etc. 
   
6. Spy-Trojan: Trojan spy refers to the applications or programs that are used by cybercriminals to spy on a person virtually by monitoring his mobile device activities. Using keylogger cybercriminals can record the keystrokes of the user and can steal valuable sensitive data like passwords, pins, financial account information, etc. 

Trojan Horse Virus Types

7. Denial-Of-Service (DOS) Attack-Trojan: The Denial of service attack is a type of attack that an attacker performs to shut down the operation capability of a device or network by sending a request to the targeted system or network till the point it becomes unable to process regular traffic.
   
8. Exploit-Trojan: Trojan-exploit is a type of virus-containing malicious code or scripts which are programmed to attack vulnerable applications or software. Usually, it happens when there is a security hole in the software while it was developing. 
   
9. Mailfinder-Trojan: Just from the name it is clear that Trojan-Mailfinder is that type of Trojan virus which are developed to extract email addresses from the attacked machine or network and then transfer the emails to the attacker via email, web, FTP, or any other preferred method by the attacker.
   
10. Fake AV(antivirus)-Trojan: Fake antivirus Trojan is that type of Trojan virus that behaves like antivirus and demands money in return for protecting the system it has affected. Mostly these Fake AV misrepresents the security status of the infected computer and shows that the system is compromised and to get out of the situation the user has to pay, and then the system will be free of security risks. 
    Eventually, after the victim pays out, the Fake AV brings up a new issue and asks for more money putting the victim in a never-ending blackmailing cycle.

Malware Distribution Chart

11. Remote Access Trojan (RAT): A Remote Access Trojan is deployed to access the victim’s computer by connecting to the device from a remote place and perform various types of malicious activities. 
    
12. Infostealer-Trojan: Infostealer is a type of Trojan virus that gain illegal access to the victim’s confidential data like, different types of login credentials, financial information. After collecting these data cybercriminals transfer these to the black market in exchange for money. 
    
13. Dropper-Trojan: These Trojan droppers are developed by the attackers in such a way that once the malicious Trojan virus is on your computer it will try escaping the detection from traditional antivirus. 
    
14. GameThief-Trojan: From the name, it is clear that these types of Trojan viruses are developed to steal the user data from the gamers’ accounts.  
    
15. SMS-Trojan: Trojan SMS is developed to infect the user’s device and then it allows the attacker to send SMS to other phone numbers.

Here are some other noteworthy Trojan horse viruses-

• Clicker-Trojan
• Notifier-Trojan
• Proxy-Trojan

How to Prevent Trojan Horse Virus Attack?

Trojan Horse Virus Prevention

Prevention is always better than cure. You can take the following precautions to be safe from Trojan horse virus attacks-

• Always abstain from downloading or installing software from an untrusted source
• Do not open an attachment or run an application sent to you via an email from an unknown person
• Always make sure to keep your software and operating system up-to-date 
• Use anti-virus software in the device to protect your device
• Always make sure to turn on the real-time protection in your operating system
• Not visiting vulnerable websites.
• Avoid engaging in suspicious web links or image icons.
• Never open attachments with extensions like, .exe, .vbs, and .bat.
• Use an anti-virus that has a built-in firewall. 
• Feel free to use premium anti-spyware applications to prevent Trojan attacks.
• Always try to avoid installing or downloading third-party applications. 
• While inserting a pen drive or hard drive in your system never autorun the device. Always scan the device first and take the necessary steps before opening the device.
• Beware of socially engineered websites or applications that will trick you to download or run unsolicited applications and programs and eventually taking control over your device or system or even the network. 
• Do not use any backdated application or operating system. Cybercriminals are known to use weak spots in them to exploit users. 

Conclusion

To be safe from any Trojan horse virus attacks human vigilance is the primary firewall to your system. Just properly follow the above steps. Hopefully, you will be safe from the most renowned Trojan attacks. 

Keep in mind that, cybercriminals are always finding new ways to hack the users. Therefore, it is highly recommended that you keep yourself updated with the latest trends. 

Techforing provides a white-glove cybersecurity service that includes Trojan horse virus removal. It is applicable for both you and the digital assets or your organization. Just E-mail us or contact us. Also you can know more from our other blogs.