Cybersecurity Revision

Cybersecurity Revision

1. Cyberattacks

   • Phishing
     • definition: sending a afake email or message pretending to be from a bank or organisation, which tricks people into trying to log on to the fake website, stealing their login details
   • Malware
     • Ransomware
       • definition: malware that encrypts users files and demands a ransom to decrypt them
     • Botnets
       • definition: a network of computers which contain malware allowing them to be controlled by a hacker
     • Keyloggers
       • definition: malware that records every keypress and sends it to a hacker for analysis
     • Definition: malicious software, designed to cause harm
   • Attempts to compromise a system or obtain unauthorised digital data (hacking)

2. Cyber defences

   • Security Software (antivirus)
     • definition: often called antivirus software even though it deals with more than just viruses, scans computers for known malware and removes it. Must be kept up to date with the latest malware definitions
   • white hat hacking
     • definition: – hacking that is done with the authorisation of the company being hacked. The hacker produces a report of all the vulnerabilities they found, so that the company can fix them
   • grey hat hacking
     • definition: – hacking done without the authorisation of the company, but with good intentions, often the company will be informed of how the hacker was able to gain access
   • backups
     • definition: keeping a copy of important data on a different system, so that it can be restored if the original is damaged
   • Techniques and systems to reduce the impact of cyberattacks

3. Encyption

   • Plaintext- the unencrypted data
   • Cipher- a method of encrypting text
   • Ciphertext- the encrypted data
   • Key- some information needed to encrypt/decrypt the data
   • Crack- to read encrypted data without being given the key beforehand
   • Brute force- crack a cipher by trying every possible key until successful
   • Statistical attack- crack a cipher by using statistics and estimates of the most likely values
   • Caesar cipher: a simple cipher, where each letter is shifted a number of places up the alphabet
   • Substitution Cipher- a simple cipher where each letter is replaced by a different letter