Cybersecurity for Beginners -Learning with Demos

Understand phishing: attackers use fraudulent emails and look-alike sites like amazon.co.uk to steal credentials. Learn to verify senders, avoid risky links, and report incidents.

Explore common password attacks, including brute force, dictionary, and social engineering, and learn how weak passwords enable breaches. Implement strong, unique passwords with 12+ characters and MFA to prevent attacks.

Watch a Kali Linux demo of a dictionary attack against an ssh login, showing how easily weak passwords from rockyou and fasttrack word lists can be cracked with Hydra.

The man-in-the-middle attack places a hacker between two parties, intercepting, viewing, and potentially altering or stealing data as traffic flows; protect data in transit with https.

Examine a man-in-the-middle attack using arp poisoning to divert traffic to a kali linux machine, demonstrated with wireshark sniffing.

Explore how SQL injection attacks exploit vulnerable inputs, with demos, and learn to prevent them using parameterized queries, prepared statements, and input validation.

Learn how SQL injection works using a vulnerable demo, showing how or one equal to one can bypass login, and how prepared statements with PDO and parameterized queries prevent it.

Explore denial-of-service attacks, including DoS and DDoS, where botnets flood a site to deny service, causing financial and reputational losses, with prevention via firewalls and traffic filtering.

Exploit cryptojacking by hijacking devices to mine cryptocurrency using unauthorized computing resources, often via malicious code on websites or phishing.

Explore the different types of hackers and their impact on cybersecurity in this beginner-friendly module. Learn how demos illustrate hacker tactics and defense strategies.

Discover how white hat hackers use ethical hacking to identify and report security vulnerabilities within legal boundaries, conduct pen testing and audits with permission for the greater good.

Gray hat hackers gain unauthorized access with no malicious intent to test security and identify vulnerabilities, unlike white hat or black hat hackers.

Discover hacktivists, hackers who use their skills to pursue political or social change, often through website defacement, DDoS, or data breaches, sometimes anonymously, with Wikileaks and Anonymous as examples.

Script kiddies misuse pre-built hacking tools with little knowledge to attack low hanging targets, causing disruptions like denial of service or website defacement.

Explore the history of cryptography from ancient Egyptian hieroglyphs through Caesar and polyalphabetic ciphers to the Enigma machine, and understand how public key cryptography enables modern secure communications.

Explore the Caesar cipher, a shift substitution encryption used by Julius Caesar. Learn how a fixed shift encrypts and decrypts messages, using plus three and minus three examples.

Explore symmetric encryption, where the same key encrypts and decrypts data, highlighting fast performance and key distribution challenges, use cases like securing communication, protecting data, and secure access to networks.

Explore how symmetric encryption uses the same key to encrypt and decrypt data with openssl, demonstrated by listing ciphers, encrypting hello.txt with aes-256-cbc, and decrypting it using the same password.

Explain asymmetric encryption, using a public and private key pair to enable secure, non-shared secret communication. It supports confidentiality, integrity, authentication, non-repudiation, with hybrid use alongside symmetric methods.

Explore how asymmetric encryption achieves authenticity, integrity, and confidentiality by encrypting with a private key and decrypting with a public key, ensuring trusted sources and untampered messages.

Practice asymmetric encryption with OpenSSL by generating public-private key pairs for two parties, exchanging keys, encrypting a message with the recipient’s public key, and decrypting with the corresponding private key.

Explore hybrid encryption, a blend of symmetric and asymmetric methods, to derive a shared symmetric key for Joy and Helene without key transfer, enabling SSL/TLS secured communication.

Explore a deep dive into various algorithms with practical demos, introducing foundational concepts in cybersecurity for beginners.

Learn how a cipher algorithm, a mathematical function, encrypts and decrypts data with a secret key, turning plaintext into ciphertext and back.

Des stands for data encryption standard, a symmetric key algorithm developed by IBM and adopted as a federal standard in 1977, using a 56-bit key and 64-bit blocks.

Explore the advanced encryption standard as a symmetric block cipher replacing the data encryption standard, with 128, 192, or 256-bit keys and multiple rounds of substitution and permutation.

Explore the NIST approved asymmetric algorithms, including RSA, DSA, ECDSA, and Diffie-Hellman, and study their roles in digital signatures and key exchange.

Demonstrate how the RSA algorithm works under the hood with a simple prime example. Generate public and private keys, encrypt, and decrypt to recover plaintext; note 2048-bit keys are recommended.

demonstrates the digital signature algorithm dsa, illustrating signing with a private key and verification with a public key, based on modular exponentiation and discrete logarithms, ensuring integrity, authentication, and non-repudiation.

Explore diffie-hellman calculations by selecting modulus p and base g, exchanging g^a mod p and g^b mod p, and deriving the shared secret s for encryption.

RSA, DSA, ECDSA, and Diffie-Hellman compare their uses, key sizes, and roles in encryption, signatures, and secure key exchange.

Explore PKI, the public key infrastructure, and how asymmetric cryptography, digital certificates, certificate authorities, and registration authorities ensure server identity and secure online transactions.

Explain hashing as a cryptographic technique that transforms data into a fixed-length digest, a one-way hash used for digital signatures, password storage, and tamper detection in data integrity checks.

Explore hashing with a simple demo using OpenSSL sha-256 to generate a digest for hello.txt. Modify the file and compare the digest to reveal tampering.

Understand that a message digest is the fixed-length output of a cryptographic hash function, such as sha-256. Signers sign the digest, not the full message, to ensure data integrity.

Understand how digital signatures within PKI verify authenticity and integrity of documents by signing the message digest with a private key and validating it with a public key.

Understand how a certificate authority verifies identity, issues digital certificates via CSR, signs with a private key, and uses root and intermediate CAs with revocation lists.

Explore a real certificate authority with DigiCert, tracing its evolution from VeriSign to a global PKI leader, highlighting SSL, multi-domain certificates, trust seals, and PKI management.

A digital certificate is a trusted digital document that verifies a site's identity, contains owner details and a public key, and is issued by a certificate authority after RA validation.

Explore how digital certificates enable HTTPS and encrypted connections, and examine the certificate chain from Facebook.com, including root and intermediate CAs, and SHA-256 with RSA.

Learn how digital certificates prevent man-in-the-middle attacks by validating certificates issued by a trusted certificate authority, using public and private keys, and browser trust checks, illustrated with HSBC.

Compare pem and pkcs12 formats, explaining base64 text vs binary encoding, what they store (certificates, private keys, crls, intermediates), password protection, and Unix vs Windows usage.

Explore how a chain of trust forms through root and intermediate CAs issuing and validating digital certificates to ensure authenticity, integrity, and secure communication.

Generate a web server csr by creating a new private key and certificate request with OpenSSL, using sha-256 RSA, protecting the key with a password, and preparing for CA signing.

Sign a certificate signing request as a CA using openssl, generating a web server certificate and illustrating the chain of trust with the CA private key.

Explore fundamental networking terms, including hosts, IP addresses, networks, subnets, switches, and routers, and learn how traffic moves within and between networks.

Master the OSI model, a seven-layer framework that standardizes network functions from physical transmission to application services, including Mac addresses, switches, routers, IP addresses, ports, encryption, and compression.

Learn how a switch connects devices on a LAN and forwards data at layer two using MAC address tables and ports.

Explore how a router connects devices across networks using a routing table and hops, acting as a gateway with security features like firewalls, VPNs, and QoS.

Discover how binary numbers convert to decimal using powers of two, calculated from right to left and summed to reveal values like 42.

Understand how IP addresses uniquely identify devices on networks, covering IPv4 and IPv6, and the network versus host parts, plus public and private IPs and static versus dynamic assignment.

Learn how subnetting divides a large IP network into smaller subnets to improve efficiency and security by borrowing bits from the host portion to create distinct address spaces.

Explain how a 32-bit subnet mask divides an IP address into network and host portions, with ones indicating network and zeros host, using 255.255.255.0 (/24) for subnetting and private networks.

Learn how ARP, the address resolution protocol, maps IP addresses to MAC addresses using requests and responses, caching, and defense against spoofing.

Explore the simulation of ARP in a LAN, showing how a host learns a destination MAC via broadcast ARP requests and an ARP cache update to enable ping.

A network packet is the unit of data with a header and payload, containing source and destination IP addresses, protocol type, and sequence numbers for reassembly.

Learn how traceroute works with a visual trace route demo from the UK to cnn.com, tracing hops, routers, and packet travel times at the speed of light.

Learn how software-based vpn services encrypt connections, hide your ip, and protect online privacy across Windows, Mac, Linux, and Android devices through a NordVPN demo that shows location masking.

Explore how firewalls act as a barrier between trusted internal networks and untrusted internet, enforcing policies to control traffic and protect enterprise devices from malware and data breaches.

A proxy server acts as an intermediary between the client and internet, masking IPs, caching content to boost performance, and enabling content filtering, malware scanning, and forensics.

Explore the demilitarized zone (DMZ) as a buffer between the internet and internal networks, using perimeter and internal firewalls and proxy servers to secure public facing services.

Connect securely to remote hosts using ssh, the secure shell protocol. It supports password or public/private key authentication, encrypts data in transit, and uses port 22 for remote access.

Analyze how SSL Pulse tracks SSL vs TLS use across popular websites, revealing trends like TLS 1.3 adoption, certificate chain completeness, and key lengths, to understand internet security posture.

Mutual TLS, or MTLS, enforces two-way authentication by requiring both client and server to present certificates signed by a trusted CA during the TLS handshake, improving security.

Explore the tcp/ip backbone of modern networks, showing how the internet and transport layers enable reliable data transmission, with addressing, routing, and packet switching across IPv4 and IPv6.

Discover how ssl, the secure socket layer, enables encrypted communication between browser and server via https. Learn about data integrity, authentication, and digital certificates issued by a trusted ca.

Discover how SSL Pulse on SSL Labs compares SSL and TLS across 135,000 websites. See trends in certificate chains, protocol support, and 2048- or 3072-bit keys, with TLS 1.3 adoption rising.