Unit 4 network and

Unit 4 network and

1. Network threats

   • Malware
     • viruses infect computers. They replicate their code in other programs. They infect other computers. They harm the computer by deleting, corrupting or modifying files
     • worms: replicates itself in order to spread to other computers. They might cause no damage to the attacked computers. They slow down networks and computers
     • Trojan horses: They have a program, game or cracked file which is something the user wants. They have negative program code which causes damage, takes control, or provides access to the computer
     • ransomware: Holds a computer hostage by locking or encrypting access to it
   • Exploiting vulnerabilities: unpatched software-if software updates and security updates are not installed then the software will be vulnerable Out-of-date anti-malware-isn’t regularly updated then it won’t be able to detect the latest viruses
     • Shoulder surfing
       • social engineering
         • phishing
   • Denial of service (DoS)
     • In a denial of service attack, a hacker will use or infect a computer so that:
       • it sends as many requests to the server as it can (known as a flood)
       • the server can’t respond fast enough so slows down or goes offline
       • In a distributed denial of service attack (DDoS), many computers are used to send the requests
   • Man-in-the-middle attack
     • A man-in-the-middle attack (MITM) allows the attacker to intercept communications between the user and server. The attacker can then:
       • eavesdrop to find passwords and personal information
       • add different information to a web page or other communication such as email
   • brute force attacks
     • In a brute force attack, a hacker will try every combination of password until the correct password is found