Kali Linux - An Ethical Hacker's Cookbook
Himanshu Sharma, 2019

NMAP CHEAT SHEET #1🔺

#1 Nmap Basic Scanning
nmap -sV [host] // Version Detection, default scan
nmap -sS [host] // SYN Stealth Scan
nmap -sU [host] // UDP Scan
nmap -sT [host] // TCP Connect() Scan
nmap -sN [host] // TCP Null Scan
nmap -sF [host] // TCP FIN Scan

#2 Nmap Host Discovery
nmap -sL [host/network] // List Scan - Discover targets by querying DNS or the targets in a network
nmap -sn [host/network] // Ping Scan - Determine if hosts are alive
nmap -Pn [host/network] // Skip host discovery

#3 Nmap Port Scanning
nmap -sC [host] // Script Scan - Execute default nmap noscripts
nmap -p [ports] [host] // Scan specific ports
nmap -F [host] // Fast Scan - Scan for the most commonly used ports

#4 Nmap Advertising Scanning
nmap -oA [filename] [host] // Output scan in all formats
nmap -O [host] // Probe Operating System fingerprints
nmap [host] --traceroute // Trace host hops

#5 Nmap Version Detection
nmap -sV [host] // Show versions of services and OS
nmap -A [host] // Advanced Scan - OS and service version and noscript scanning
nmap --noscript [name] [host] // Execute a custom noscript

#6 Nmap Timing Options
nmap -T[0-5] [host] // Timing for scans

#7 Nmap Firewall/IDS Evasion
nmap --spoof-mac [address] // Changes source MAC address
nmap -D RND:10 [host] // Decoy Scan - Appear to scan from multiple hosts
nmap -f // Fragmented Packets - Fragment Packets
nmap -Pn [host] // Skip host discovery
nmap --data-length [length] // Append random data to packet

⚠️List of terms used in the field of hacking.⚠️

⏭Adware − Adware is software designed to force pre-chosen ads to display on your system.

➖ Attack − An attack is an action that is done on a system to get its access and extract sensitive data.

➖ Back door − A back door, or trap door, is a hidden entry to a computing device or software that bypasses security measures, such as logins and password protections.

➖ Bot − A bot is a program that automates an action so that it can be done repeatedly at a much higher rate for a more sustained period than a human operator could do it. For example, sending HTTP, FTP or Telnet at a higher rate or calling noscript to create objects at a higher rate.

➖ Botnet − A botnet, also known as zombie army, is a group of computers controlled without their owners’ knowledge. Botnets are used to send spam or make denial of service attacks.

➖ Brute force attack − A brute force attack is an automated and the simplest kind of method to gain access to a system or website. It tries different combination of usernames and passwords, over and over again, until it gets in.

➖ Buffer Overflow − Buffer Overflow is a flaw that occurs when more data is written to a block of memory, or buffer, than the buffer is allocated to hold.

➖ Clone phishing − Clone phishing is the modification of an existing, legitimate email with a false link to trick the recipient into providing personal information.

➖ Cracker − A cracker is one who modifies the software to access the features which are considered undesirable by the person cracking the software, especially copy protection features.

➖ Denial of service attack (DoS) − A denial of service (DoS) attack is a malicious attempt to make a server or a network resource unavailable to users, usually by temporarily interrupting or suspending the services of a host connected to the Internet.

➖ DDoS − Distributed denial of service attack.

➖ Exploit Kit − An exploit kit is software system designed to run on web servers, with the purpose of identifying software vulnerabilities in client machines communicating with it and exploiting discovered vulnerabilities to upload and execute malicious code on the client.

➖ Exploit − Exploit is a piece of software, a chunk of data, or a sequence of commands that takes advantage of a bug or vulnerability to compromise the security of a computer or network system.

➖ Firewall − A firewall is a filter designed to keep unwanted intruders outside a computer system or network while allowing safe communication between systems and users on the inside of the firewall.

➖ Keystroke logging − Keystroke logging is the process of tracking the keys which are pressed on a computer (and which touchscreen points are used). It is simply the map of a computer/human interface. It is used by gray and black hat hackers to record login IDs and passwords. Keyloggers are usually secreted onto a device using a Trojan delivered by a phishing email.

➖ Logic bomb − A virus secreted into a system that triggers a malicious action when certain conditions are met. The most common version is the time bomb.

➖ Malware − Malware is an umbrella term used to refer to a variety of forms of hostile or intrusive software, including computer viruses, worms, Trojan horses, ransomware, spyware, adware, scareware, and other malicious programs.

➖ Master Program − A master program is the program a black hat hacker uses to remotely transmit commands to infected zombie drones, normally to carry out Denial of Service attacks or spam attacks.

➖ Phishing − Phishing is an e-mail fraud method in which the perpetrator sends out legitimate-looking emails, in an attempt to gather personal and financial information from recipients.

➖ Phreaker − Phreakers are considered the original computer hackers and they are those who break into the telephone network illegally, typically to make free long distance phone calls or to tap phone lines.

What is a web application? What are Web Threats?

A web application (aka website) is an application based on the client-server model. The server provides the database access and the business logic. It is hosted on a web server. The client application runs on the client web browser. Web applications are usually written in languages such as Java, C#, and VB.Net, PHP, ColdFusion Markup Language, etc. the database engines used in web applications include MySQL, MS SQL Server, PostgreSQL, SQLite, etc.
Most web applications are hosted on public servers accessible via the Internet. This makes them vulnerable to attacks due to easy accessibility. The following are common web application threats.

SQL Injection – the goal of this threat could be to bypass login algorithms, sabotage the data, etc.

Denial of Service Attacks – the goal of this threat could be to deny legitimate users access to the resource

Cross Site Scripting XSS – the goal of this threat could be to inject code that can be executed on the client side browser.

Cookie/Session Poisoning – the goal of this threat is to modify cookies/session data by an attacker to gain unauthorized access.

Form Tampering – the goal of this threat is to modify form data such as prices in e-commerce applications so that the attacker can get items at reduced prices.

Code Injection – the goal of this threat is to inject code such as PHP, Python, etc. that can be executed on the server. The code can install backdoors, reveal sensitive information, etc.

Defacement – the goal of this threat is to modify the page been displayed on a website and redirecting all page requests to a single page that contains the attacker’s message.

Here’s how OTPs work in more detail:

Step 1: The user wants to log in to a website and is asked to enter a username, cell phone number, or email.

Step 2: The server generates an OTP with an expiration time.

Step 3: The server sends the OTP to the user’s device via SMS or email.

Step 4: The user enters the OTP received in the login box.

Step 5-6: The server compares the generated OTP with the one the user entered. If they match, login is granted.

Why did the password manager break up with the password?

Because it wasn't secure enough! 🙈😂

Happy World Password Day!

Today is a great reminder to prioritise strong and secure passwords to protect your personal and financial information online.

Password managers like LastPass,
1Password,
Dashlane,
KeePass,
and Bitwarden

can help you generate and store secure passwords for all your accounts.

Programming languages and their uses in Ethical hacking :

Programming languages are essential tools for ethical hackers. They are used for tasks such as vulnerability testing, penetration testing, and developing exploits. Here are some programming languages that are commonly used in ethical hacking and their specific uses:

Python: Python is a high-level programming language that is easy to learn and widely used in the field of cybersecurity. It is used for tasks such as penetration testing, reverse engineering, and noscripting. Python has a large community of developers who create and maintain libraries that can be used for security purposes, such as Scapy for packet manipulation, PyCrypto for encryption and decryption, and BeautifulSoup for web scraping.

Ruby: Ruby is another high-level programming language that is popular in the cybersecurity community. It is used for developing exploits and automating tasks. Metasploit, one of the most widely used penetration testing tools, is written in Ruby.

C/C++: C and C++ are low-level programming languages that are used for writing exploits and developing rootkits. They are also used for reverse engineering and vulnerability testing. Many of the tools used in ethical hacking, such as Nmap, Wireshark, and Tcpdump, are written in C/C++.

JavaScript: JavaScript is a popular noscripting language that is used for web application security testing. It is used for tasks such as cross-site noscripting (XSS) and cross-site request forgery (CSRF) testing. Many web-based security tools, such as Burp Suite, are written in JavaScript.

Bash: Bash is a shell noscripting language that is used for automating tasks and creating custom noscripts. It is commonly used for tasks such as password cracking and network scanning.

SQL: SQL is a database programming language that is used for exploiting and testing SQL injection vulnerabilities in web applications.

In addition to these languages, there are many other programming languages that can be used in ethical hacking, such as Perl, PHP, and Java. The choice of programming language will depend on the specific task at hand and the preference of the individual ethical hacker.

How to Surf Internet Anonymously :

Use a virtual private network (VPN): A VPN allows you to create a secure and encrypted connection to the internet, which can help to keep your browsing activity private. When you use a VPN, your internet traffic is routed through a remote server, which masks your IP address and encrypts your data. This makes it much harder for anyone to track your online activity.

Use Tor Browser: The Tor Browser is a free, open-source web browser that uses the Tor network to route your internet traffic through a series of encrypted relays. This makes it very difficult for anyone to trace your online activity back to your computer.

Use a private browsing mode: Most web browsers offer a private browsing mode, which can help to keep your browsing activity private. When you use a private browsing mode, your browser doesn't store cookies, temporary files, or browsing history. However, it's important to note that private browsing mode doesn't make you completely anonymous, as your internet service provider (ISP) can still see your activity.

Use a privacy-focused search engine: Traditional search engines like Google and Bing store your search history and other personal data. Using a privacy-focused search engine like DuckDuckGo or StartPage can help to keep your searches private.

Thanks for Reading ❤️

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