CS4286 Cheat Sheet

2 Symmetric Cryptography

Classical cryptography

3 Number theory

Extended Euclid’s algorithm

def extendedEuclidean(a, b):
    if b == 0:
        return a, 1, 0
        d, x, y = extendedEuclidean(b, a % b)
        return d, y, x - (a // b) * y

4 Public key cryptography

5 Integrity

6 Authentication

7 Key management

8 Computer security


MalwareDescriptionHost ProgramReplicationExample
Backdoora secret entry point into a program, usually inserted during code development or testingyesnoxz backdoor
Logic bombcode that is set to explode when certain conditions are metyesnorailway service in Poland, 2024
Trojan horsehidden code that perform hidden functionyesno
Virusinfect other programs by modifying themyesother files
Bacteriareplicate itself to take up resourcesnolaunch more instances
Wormspreading to other machines over networknoover networkILOVEYOU (2000)
Ransomwareencrypt user data and demand payment for decryptionnonoWannacry

9 Network Security