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Phreaking is an early phone hacking method from the 1960s and 70s where hackers used special sounds to trick telephone systems. They played a 2600 Hz tone to control the phone switches and make free long-distance calls. Tools called "blue boxes" were made to create these tones, and famous phreakers like John Draper (“Captain Crunch”) used a cereal box whistle that made the same tone.

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WannaCry was a ransomware attack that occurred in May 2017, infecting over 2,00,000 computers across 150 countries. It encrypted users’ data and demanded payment in Bitcoin cryptocurrency to restore access, hence the name “WannaCry” because victims were left helpless.

• It exploited a vulnerability in Microsoft Windows (SMB protocol).
• The attack affected major organizations like UK’s National Health Service (NHS), FedEx, and Renault.

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Aircrack-ng is a widely used toolset for Wi-Fi hacking and security testing. It includes tools for capturing network traffic, testing wireless card capabilities, and cracking WEP (Wired Equivalent Privacy), WPA (Wi-Fi Protected Access), and WPA2 encryption keys.

It supports various attacks such as deauthentication and replay attacks to capture handshake data needed for cracking passwords. This tool is popular among security professionals and hackers for analyzing and testing Wi-Fi network security.

Wireshark is a powerful packet analyzer useful for inspecting network traffic and can assist in wireless troubleshooting or analysis, but it is not primarily a Wi-Fi cracking tool.

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OPENING POP-UPS is not a way to protect your system, in fact, it is one of the most common ways malware spreads. Pop-ups may contain malicious links, fake ads, or phishing content that can install harmful software on your device.

To stay protected from malware, never click on suspicious pop-ups, use firewalls and antivirus software, and regularly back up important data.

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The On-Screen Keyboard is a Virtual Keyboard provided by an operating system that displays QWERTY keys on the screen that allows users to input text by clicking keys using a mouse or touch input instead of a physical keyboard.

Although keyloggers can exploit it by recording screen activities, it is still safer than hardware keyboards, which can be compromised by physical keyloggers.

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A Plug-In is a complete software component developed by a third party that is installed on a host application, such as a web browser, to extend its capabilities. 
Plug-Ins allow browsers to perform additional functions like playing videos, displaying PDFs, or running multimedia content. Examples include Adobe Flash Player, Java Plug-in, PDF Viewer etc.

Plug-Ins differ from Add-Ons or Extensions, which are usually smaller tools that modify or enhance the browser’s behavior, while plug-ins provide additional functionality through external software integration.
 

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A Computer Virus is a type of malicious software that attaches itself to files or programs and can spread from one system to another. Just like a biological virus, it has a life cycle made up of different stages.

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A Firewall is a network security system that monitors and controls incoming and outgoing network traffic based on predetermined security rules. Its primary purpose is to protect a trusted internal (LAN) network from untrusted external networks like the Internet.

Firewalls can be hardware, software, or a combination of both, and act as a barrier or gatekeeper between networks by allowing or blocking data packets depending on security policies.

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Phishing is when someone tricks you to give your personal information like passwords, bank details, or ID numbers by sending fake emails, messages, or websites that look real. Hackers use this stolen information to steal your identity, make purchases, or commit fraud.

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Antivirus software is also called Antimalware, because it protects the system not only from viruses but also from other malicious software like worms, trojans, spyware, and ransomware.

MALWARE / MALICIOUS SOFTWARE TYPES:

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In network security, communication between two devices can be intercepted by malicious users. Eavesdropping is the unauthorized real-time interception or monitoring of private communication between two entities over a network. It can involve listening to voice calls, reading emails or data transmissions without consent, exploiting unsecured or weakly secured communication channels.

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A Denial of Service (DoS) attack is a type of cyberattack that aims to make a computer system or network unavailable to its legitimate users. It does this by overloading the system with excessive requests, causing it to slow down or crash completely.

• Phishing tries to steal sensitive data like passwords.
• Spamming floods users with unwanted messages.
• Virus infects and damages files or programs.

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In public key cryptography, a Digital Signature is created by the sender using their private key (Sender Private Key). To verify that the signature is authentic and that the message has not been altered, the receiver uses the Sender’s Public Key. This ensures the signature was indeed generated by the sender and provides authentication and integrity.

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A Firewall is a network security device or software that acts as a barrier between a trusted internal network and an untrusted external network, like the internet.
Its main purpose is to monitor data packets entering or leaving the network and decide whether to allow or block them based on predefined security rules.

Firewalls help protect systems from hackers, viruses, and unauthorized access. They can be implemented using hardware, software, or both, depending on the system’s security needs. 
Firewalls ensure that only packets from trusted source addresses are allowed to enter the organization’s network.

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Cryptography, the science of securing communication by using encryption and decryption techniques.

The information that gets transformed during encryption is called Plain Text. Plain text refers to the original, human-readable data such as messages, files, or any sensitive information.

Encryption is the process of converting readable information, called plain text, into an unreadable or scrambled format known as Cipher Text, using algorithms and cryptographic keys. The Cipher Text, ensures that unauthorized users cannot understand it without the proper key.

Decryption is the reverse of encryption. It transforms encrypted data (cipher text) back into its original readable form (plain text) using a decryption key.

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Eavesdropping is the act of secretly listening to or capturing private communication between two parties over a network. 
It is a type of network attack where an unauthorized person monitors data that is being transmitted between hosts. This can include listening to phone calls, reading emails, or intercepting messages exchanged over the internet.

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A Boot Virus is a type of computer virus that infects the boot sector of a storage device or the key operating system files that help a computer start. When the infected computer is turned on, the virus is automatically loaded into memory before the operating system starts.

A Worm is a self-replicating malicious program that spreads without needing to attach itself to any file or program. Unlike ordinary viruses, worms can travel automatically through networks and the internet.

Zombies are computers that have been secretly infected with malicious software and are controlled remotely by a hacker, often without the owner’s knowledge. These compromised machines are used to perform tasks such as sending spam emails, spreading viruses, or participating in large-scale network attacks.

A Denial-of-Service (DoS) attack is an attempt by an attacker to make a computer or network service unavailable to its users. In this attack, the hacker sends a massive number of requests or data packets to a target server or website.

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The Creeper virus, created in 1970s by Bob Thomas at BBN Technologies, is considered the first computer virus. It was an experimental self-replicating program that moved across ARPANET and displayed the message: "I'M THE CREEPER, CATCH ME IF YOU CAN!".

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Hacktivism is the combination of "hacking" and "activism." It refers to the act of breaking into computer systems or networks with the intention of promoting political or social causes (not for financial gain).
Hacktivists use hacking techniques to raise awareness, protest against injustices, or support specific movements by targeting organizations, governments, or corporations they oppose.
Common hacktivist activities include:

• Website defacements.
• Distributed Denial of Service (DDoS) attacks.
• Leaking confidential information to expose organizations or governments.

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In E-banking and digital payments, security is a major concern. One of the common fraud techniques used by criminals is called Skimming. The skimming refers to the illegal practice of stealing credit card or debit card details using a small device called a skimmer, often hidden at ATMs or Point-of-Sale (POS) terminals.

Fraudsters use skimmers to secretly copy the information from a card’s magnetic strip. They may also use a hidden camera or fake keypad to capture the PIN. The stolen data is used to create counterfeit cards or make unauthorized transactions.

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In public key cryptography, a Digital Signature is created by the sender using their private key. To verify that the signature is authentic and that the message has not been altered, the receiver uses the sender’s public key. This ensures the signature was indeed generated by the sender and provides authentication and integrity.

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Cyber Security is the practice of protecting computers, networks, programs, and data from unauthorized access, attacks, or damage. The main goals of cyber security are Confidentiality, Integrity, Availability (CIA).

CYBER SECURITY MEASURES:

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A Firewall is a network security device or software that monitors and controls incoming and outgoing traffic based on predefined security rules. Common types of firewalls include:

1. Packet Filtering Firewall: Inspects packets at the network layer and allows or blocks them based on IP addresses, ports, or protocols.
2. Stateful Inspection Firewall: Monitors active connections and makes decisions based on the state and context of traffic.
3. Application Proxy Firewall: Acts as an intermediary between users and services, inspecting application-level data.

ITU-T X.509 is a standard for Public Key Infrastructure (PKI) certificates and certificate formats used for authentication and trust, not for traffic filtering.

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Password Cracking is the process of attempting to discover or recover a password to gain unauthorized or authorized access to a system, account, or network. It is performed either to recover forgotten passwords or, more maliciously, to break into systems by guessing the correct password.

Attackers use various automated tools and techniques to systematically guess or decrypt passwords by exploiting weak or commonly used ones.

1. Guessing, the attacker manually guesses passwords based on known information about the victim such as names, birthdays, or common passwords.
2. Brute Force Attack, this method tries every possible combination of characters until the correct password is found. It is simple but can be time-consuming, effective mostly against short or weak passwords.
3. Syllable Attack, a syllable (pronounceable) attack makes likely passwords by joining small, easy-to-say parts (syllables), the kind of words people choose because they are memorable. For example, it might try combinations like "pa" + "ss" + "word" is "password" or "su" + "ra" + "ku" is "suraku".
4. Dictionary Attack, it uses a precompiled list (dictionary) of common words, phrases, or known passwords to guess the correct password. This is faster than brute force if the password is common or predictable.
5. Hybrid Attack, it combines dictionary and brute force methods by using dictionary words with added numbers or symbols. This expands the guessing capability while focusing on likely password patterns.
6. Credential Stuffing, it utilizes leaked username-password pairs from previous breaches to try and gain unauthorized access to accounts where users reuse passwords across sites.
7. Rainbow Table Attack, it uses precomputed tables of hashed passwords to reverse the hashing process and find the original password quickly, especially if weak or unsalted hashes are used.

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In network security, communication between two devices can be intercepted by malicious users. Eavesdropping is the unauthorized real-time interception or monitoring of private communication between two entities over a network. It can involve listening to voice calls, reading emails or data transmissions without consent, exploiting unsecured or weakly secured communication channels.
Phishing : Fraudulent attempt to obtain or steal sensitive information like passwords.
Virus : Malicious Software (Malware) designed to damage or disrupt systems.

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A Rootkit is a type of Malicious Software (Malware) designed to gain unauthorized administrator-level control over an operating system. Once installed, it alters the normal functioning of the OS, allowing the attacker to take full control of the system and act as its administrator.

Rootkits are especially dangerous because they actively hide themselves, making detection and removal very difficult.