Computer And Networks Security Flashcards
Firewall
Barrier between internal network and Internet or untrusted networks.
Prevents unauthorised access and protect from types of cyberthreats.
Virus
Infects some executable software which causes that software to spread the virus.
Contain payload which performs other malicious actions.
Worm
Self replicate and actively transmit itself over a network to infect other computers.
They do not need to attach themselves to an existing program.
They cause harm to networks by consuming bandwidth.
Spyware
Collects small amounts of data about users without their knowledge.
Can slow computers by reporting internet surfing habits, changing settings, installing additional software and redirecting web browsers.
Adware
Automatically displays or download ads to computer.
Usually integrated with spyware and displays ads related from spying.
Phishing
Attempting to acquire sensitive information such as usernames, passwords, bank account info’s by masquerading as a trustworthy entity.
Social engineering
Act of manipulating people into performing actions or divulging confidential information rather than by breaking in or using technical vulnerabilities.
Leads to data breaches, unauthorized access, and financial loss.
How to protect computer from attacks
Keep software up to date, use antivirus software.
Use strong passwords, unique one and never reuse them.
Install and maintain firewalls helps block unauthorized access to network.
Use encryption to make data unreadable to unauthorized parties.
Implement access controls to ensure only authorized users access your network.
Regularly back up data to recover it in case of cyberattacks or disaster.
Use 2 step verification
3 functions of antivirus software
Scan and Detection
Removal and Quarantine
Real time Protection
Describe how malware can affect a system’s reliability and performance.
System crash
Sluggish performance
Reduced storage capacity
Network congestion
System instability
Data loss
BIOMETRIC SYSTEMS
verify or recognize identity of a person based on their unique physical or behavioral characteristics, such as fingerprints, facial recognition, iris/retina scans, voice recognition, or DNA analysis.
Used for security purposes.
Describe THREE characteristics of biometric security systems
Uniqueness: rely on unique biological or behavioral characteristics specific to each individual.
Accuracy: measured in terms of False Acceptance Rate (FAR) and False Rejection Rate (FRR).
Security: more secure than passwords or PINs, because biometric traits cannot be easily replicated or stolen.
Advantages of biometric systems
High security, harder to gain access.
Convenient and fast way for users to authenticate their identity without remembering passwords or carry identification cards.
More accurate and easy to use.
Disadvantages of biometric systems
Cost: expensive to implement and maintain hardware, software, and infrastructure required for biometric systems.
Cybersecurity
Monitor and protect against online attacks.
Ex: hacking, snooping, phishing, online spying.
Hacking
Someone who seeks to breach defenses and exploit weaknesses in computer system or network.
Ransomware
Denies you access to your files or computer until you pay a ransom.
Spam
Untrusted bulk email,electronic equivalent of junk email that comes to your inbox.
Spam uses bandwidth and fills up databases.
Discuss three different methods of authenticating a user at the point of login
Knowledge-Based Authentication:
* Requires user-specific information like password, PIN, security question answer.
* Vulnerable to phishing and brute force attacks.
Possession-Based Authentication:
* Relies on user’s possession of physical or digital item such as OTP, security token sent to their mobile device.
* Enhances security by requiring external device.
* Can be compromised if device is lost or stolen.
Biometric Authentication:
* Utilizes unique biological traits like fingerprint, facial recognition, iris scanning.
* Difficult to replicate, may face challenges like false positives or environmental factors.
3 threats against computer network from external attackers
Malware attacks
Distributed denial of services attacks.
Social engineering attacks
Trojan Horse
Pretends to be legitimate software.
Actually, carry out hidden harmful functions.
Access Control List
Used in operating systems, network, other security systems
Ensure only authorized users or systems can access sensitive resources, such as files or network
What is malware ?
Malware refers to any software intentionally designed to cause damage to a computer, server, network, or device.
This includes viruses, worms, ransomware, spyware, adware, and other harmful programs created by cybercriminals to steal data, disrupt operations, or gain unauthorized access.
Denial of Service (DOS)
A type of cyberattack designed to disable, shut down, or disrupt network, website, or service.
Floods a server with traffic, making a website or resource unavailable.
Causes service disruption and potential financial loss.
Pop up blocker
Prevents wen browsers for displaying pop-up windows or ads that automatically appear on user’s screen.
Block code that triggers popup windows or filter URLs or web scripts.
Pop-up can be annoying, disruptive, and dangerous .
Modern web browsers have in built pop-up blocker.
Anti Spyware
Man-in-the-Middle (MITM)
Intercepting communication between two parties to steal or alter data.
Compromises data integrity and confidentiality.
EX: Eavesdropping on an unencrypted email exchange.
Sniffing
Intercepting and analyzing network traffic to capture sensitive information.
Leads to data theft and privacy violations.
Example:
Using Wireshark to capture login credentials on a Wi-Fi network.
Scanning
Probing a network to discover active hosts, open ports, and services.
Helps attackers identify vulnerabilities for future exploitation.
Example:
Using Nmap to find open ports on a server.
