running on the system to control the system further.

Rootkit

This type of trojan infects a computer and disables anti-virus or other security programs so that it can infect the computer further. You can get more information on rootkits here :

• What is a rootkit?
• How to detect rootkits with chkrootkit?
• How to remove rootkits with rkhunter?
• What is ZeroAccess Rootkit?

Trojan-Banker

They steal sensitive user data like bank account passwords, credit card numbers, etc from the infected computer.

Trojan-DDoS

This type of trojan uses the infected computers to perform a DDoS or Distributed Denial of Service attack on a target computer (What is a DDoS attack and how to protect your servers from DDoS attacks ?).

Trojan-FakeAntiVirus

They misrepresent themselves to appear as a security program and often report that the computer is infected, though it is actually false. Their main purpose is to appear useful to the user so that the user installs it and gets infected by the Trojans.

Trojan-GameThief

They steal account information for online gamers.

Trojan-InstantMessenger

They steal login information of Instant Messaging users.

Trojan-Ransomware

The purpose of Trojan-Ransomware is to infect the computer and extort money from the user.

Trojan-SMS

They cost the user a huge amount of money by sending text messages to some premium-rate phone numbers without the user’s knowledge.

Trojan-Spy

They spy on the user using a keylogger, webcam, etc, and collect sensitive data.

Trojan-MailFinder

They harvest email addresses from the infected computer.

Trojan-Joke

They play annoying sounds on the speaker or display taunting messages on the screen, but otherwise comparatively less harmful.

How to prevent trojans?

• Trojans mostly use some social engineering techniques to infect a victim’s computer. So, do not click on any link if you are not very sure of its authenticity.
• Do not open email attachments if you are not sure of the sender.
• Always avoid downloading software from untrusted sources.
• Trojans often exploit security vulnerabilities of commonly used software to infect a computer. So, always keep all commonly used software on your computer updated with recent security patches.
• Update your Operating Systems with recent patches for the same reason.
• Use anti-malware programs from trusted sources and keep them updated regularly.
• Configure the firewall (What is a firewall and how does it work ?) on your system properly.

Security Fundamentals Practice Tests

The Security Fundamentals Practice Tests test one’s fundamental knowledge of cyber security. The practice tests are good for those who are preparing for various certification exams like the CCNA, CCNP, or CompTIA. They are also good for students and IT/security professionals who want to improve their understanding of cybersecurity.