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https://github.com/trimstray/the-book-of-secret-knowledge

A collection of inspiring lists, manuals, cheatsheets, blogs, hacks, one-liners, cli/web tools and more.
https://github.com/trimstray/the-book-of-secret-knowledge

List: the-book-of-secret-knowledge

awesome awesome-list bsd cheatsheets devops guidelines hacking hacks howtos linux lists manuals one-liners pentesters resources search-engines security security-researchers sysops

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A collection of inspiring lists, manuals, cheatsheets, blogs, hacks, one-liners, cli/web tools and more.

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README

        



Master

"Knowledge is powerful, be careful how you use it!"

A collection of inspiring lists, manuals, cheatsheets, blogs, hacks, one-liners, cli/web tools, and more.




Pull Requests


MIT License






Created by
trimstray and
contributors


****

## :notebook_with_decorative_cover:  What is it?

This repository is a collection of various materials and tools that I use every day in my work. It contains a lot of useful information gathered in one piece. It is an invaluable source of knowledge for me that I often look back on.

## :restroom:  For whom?

For everyone, really. Here everyone can find their favourite tastes. But to be perfectly honest, it is aimed towards System and Network administrators, DevOps, Pentesters, and Security Researchers.

## :information_source:  Contributing

If you find something which doesn't make sense, or something doesn't seem right, please make a pull request and please add valid and well-reasoned explanations about your changes or comments.

A few simple rules for this project:

- inviting and clear
- not tiring
- useful

These below rules may be better:

- easy to contribute to (Markdown + HTML ...)
- easy to find (simple TOC, maybe it's worth extending them?)

Url marked **\*** is temporary unavailable. Please don't delete it without confirming that it has permanently expired.

Before adding a pull request, please see the **[contributing guidelines](.github/CONTRIBUTING.md)**. You should also remember about this:

```diff
+ This repository is not meant to contain everything but only good quality stuff.
```

All **suggestions/PR** are welcome!

### Code Contributors

This project exists thanks to all the people who contribute.

### Financial Contributors








## :newspaper:  RSS Feed & Updates

GitHub exposes an [RSS/Atom](https://github.com/trimstray/the-book-of-secret-knowledge/commits.atom) feed of the commits, which may also be useful if you want to be kept informed about all changes.

## :ballot_box_with_check:  ToDo

- [ ] Add new stuff...
- [ ] Add useful shell functions
- [ ] Add one-liners for collection tools (eg. CLI Tools)
- [ ] Sort order in lists

New items are also added on a regular basis.

## :anger:  Table of Contents

Only main chapters:

- **[CLI Tools](#cli-tools-toc)**
- **[GUI Tools](#gui-tools-toc)**
- **[Web Tools](#web-tools-toc)**
- **[Systems/Services](#systemsservices-toc)**
- **[Networks](#networks-toc)**
- **[Containers/Orchestration](#containersorchestration-toc)**
- **[Manuals/Howtos/Tutorials](#manualshowtostutorials-toc)**
- **[Inspiring Lists](#inspiring-lists-toc)**
- **[Blogs/Podcasts/Videos](#blogspodcastsvideos-toc)**
- **[Hacking/Penetration Testing](#hackingpenetration-testing-toc)**
- **[Your daily knowledge and news](#your-daily-knowledge-and-news-toc)**
- **[Other Cheat Sheets](#other-cheat-sheets-toc)**
- **[Shell One-liners](#shell-one-liners-toc)**
- **[Shell Tricks](#shell-tricks-toc)**
- **[Shell Functions](#shell-functions-toc)**

## :trident:  The Book of Secret Knowledge (Chapters)

#### CLI Tools  [[TOC]](#anger-table-of-contents)

##### :black_small_square: Shells


   GNU Bash - is an sh-compatible shell that incorporates useful features from the Korn shell and C shell.

   Zsh - is a shell designed for interactive use, although it is also a powerful scripting language.

   tclsh - is a very powerful cross-platform shell, suitable for a huge range of uses.

   bash-it - is a framework for using, developing and maintaining shell scripts and custom commands.

   Oh My ZSH! - is the best framework for managing your Zsh configuration.

   Oh My Fish - the Fishshell framework.

   Starship - the cross-shell prompt written in Rust.

   powerlevel10k - is a fast reimplementation of Powerlevel9k ZSH theme.

##### :black_small_square: Shell plugins


   z - tracks the folder you use the most and allow you to jump, without having to type the whole path.

   fzf - is a general-purpose command-line fuzzy finder.

   zsh-autosuggestions - Fish-like autosuggestions for Zsh.

   zsh-syntax-highlighting - Fish shell like syntax highlighting for Zsh.

   Awesome ZSH Plugins - A list of frameworks, plugins, themes and tutorials for ZSH.

##### :black_small_square: Managers


   Midnight Commander - is a visual file manager, licensed under GNU General Public License.

   ranger - is a VIM-inspired filemanager for the console.

   nnn - is a tiny, lightning fast, feature-packed file manager.

   screen - is a full-screen window manager that multiplexes a physical terminal.

   tmux - is a terminal multiplexer, lets you switch easily between several programs in one terminal.

   tmux-cssh - is a tool to set comfortable and easy to use functionality tmux-sessions.

##### :black_small_square: Text editors


   vi - is one of the most common text editors on Unix.

   vim - is a highly configurable text editor.

   emacs - is an extensible, customizable, free/libre text editor, and more.

   micro - is a modern and intuitive terminal-based text editor.

   neovim - is a free open source, powerful, extensible and usable code editor.

   spacemacs - a community-driven Emacs distribution.

   spacevim - a community-driven vim distribution.

##### :black_small_square: Files and directories


   fd - is a simple, fast and user-friendly alternative to find.

   ncdu - is an easy to use, fast disk usage analyzer.

##### :black_small_square: Network


   PuTTY - is an SSH and telnet client, developed originally by Simon Tatham.

   Mosh - is a SSH wrapper designed to keep a SSH session alive over a volatile connection.

   Eternal Terminal - enables mouse-scrolling and tmux commands inside the SSH session.

   nmap - is a free and open source (license) utility for network discovery and security auditing.

   zmap - is a fast single packet network scanner designed for Internet-wide network surveys.

   Rust Scan - to find all open ports faster than Nmap.

   masscan - is the fastest Internet port scanner, spews SYN packets asynchronously.

   pbscan - is a faster and more efficient stateless SYN scanner and banner grabber.

   hping - is a command-line oriented TCP/IP packet assembler/analyzer.

   mtr - is a tool that combines the functionality of the 'traceroute' and 'ping' programs in a single tool.

   mylg - utility which combines the functions of the different network probes in one diagnostic tool.

   netcat - utility which reads and writes data across network connections, using the TCP/IP protocol.

   socat - utility which transfers data between two objects.

   tcpdump - is a powerful command-line packet analyzer.

   tshark - is a tool that allows us to dump and analyze network traffic (wireshark cli).

   Termshark - is a simple terminal user-interface for tshark.

   ngrep - is like GNU grep applied to the network layer.

   netsniff-ng - is a Swiss army knife for your daily Linux network plumbing if you will.

   sockdump - dump unix domain socket traffic.

   stenographer - is a packet capture solution which aims to quickly spool all packets to disk.

   tcpterm - visualize packets in TUI.

   bmon - is a monitoring and debugging tool to capture networking related statistics and prepare them visually.

   iptraf-ng - is a console-based network monitoring program for Linux that displays information about IP traffic.

   vnstat - is a network traffic monitor for Linux and BSD.

   iPerf3 - is a tool for active measurements of the maximum achievable bandwidth on IP networks.

   ethr - is a Network Performance Measurement Tool for TCP, UDP & HTTP.

   Etherate - is a Linux CLI based Ethernet and MPLS traffic testing tool.

   echoip - is a IP address lookup service.

   Nemesis - packet manipulation CLI tool; craft and inject packets of several protocols.

   packetfu - a mid-level packet manipulation library for Ruby.

   Scapy - packet manipulation library; forge, send, decode, capture packets of a wide number of protocols.

   impacket - is a collection of Python classes for working with network protocols.

   ssh-audit - is a tool for SSH server auditing.

   aria2 - is a lightweight multi-protocol & multi-source command-line download utility.

   iptables-tracer - observe the path of packets through the iptables chains.

   inception - a highly configurable tool to check for whatever you like against any number of hosts.

   mRemoteNG - a fork of mRemote, multi-tabbed PuTTy on steroids!

##### :black_small_square: Network (DNS)


   dnsdiag - is a DNS diagnostics and performance measurement tools.

   fierce - is a DNS reconnaissance tool for locating non-contiguous IP space.

   subfinder - is a subdomain discovery tool that discovers valid subdomains for websites.

   sublist3r - is a fast subdomains enumeration tool for penetration testers.

   amass - is tool that obtains subdomain names by scraping data sources, crawling web archives, and more.

   namebench - provides personalized DNS server recommendations based on your browsing history.

   massdns - is a high-performance DNS stub resolver for bulk lookups and reconnaissance.

   knock - is a tool to enumerate subdomains on a target domain through a wordlist.

   dnsperf - DNS performance testing tools.

   dnscrypt-proxy 2 - a flexible DNS proxy, with support for encrypted DNS protocols.

   dnsdbq - API client providing access to passive DNS database systems.

   grimd - fast dns proxy, built to black-hole internet advertisements and malware servers.

   dnstwist - detect typosquatters, phishing attacks, fraud, and brand impersonation.

##### :black_small_square: Network (HTTP)


   curl - is a command line tool and library for transferring data with URLs.

   kurly - is an alternative to the widely popular curl program, written in Golang.

   HTTPie - is an user-friendly HTTP client.

   wuzz - is an interactive cli tool for HTTP inspection.

   h2spec - is a conformance testing tool for HTTP/2 implementation.

   h2t - is a simple tool to help sysadmins to hardening their websites.

   htrace.sh - is a simple Swiss Army knife for http/https troubleshooting and profiling.

   httpstat - is a tool that visualizes curl statistics in a way of beauty and clarity.

   httplab - is an interactive web server.

   Lynx - is a text browser for the World Wide Web.

   Browsh - is a fully interactive, real-time, and modern text-based browser.

   HeadlessBrowsers - a list of (almost) all headless web browsers in existence.

   ab - is a single-threaded command line tool for measuring the performance of HTTP web servers.

   siege - is an http load testing and benchmarking utility.

   wrk - is a modern HTTP benchmarking tool capable of generating significant load.

   wrk2 - is a constant throughput, correct latency recording variant of wrk.

   vegeta - is a constant throughput, correct latency recording variant of wrk.

   bombardier - is a fast cross-platform HTTP benchmarking tool written in Go.

   gobench - http/https load testing and benchmarking tool.

   hey - HTTP load generator, ApacheBench (ab) replacement, formerly known as rakyll/boom.

   boom - is a script you can use to quickly smoke-test your web app deployment.

   SlowHTTPTest - is a tool that simulates some Application Layer Denial of Service attacks by prolonging HTTP.

   gobuster - is a free and open source directory/file & DNS busting tool written in Go.

   ssllabs-scan - command-line reference-implementation client for SSL Labs APIs.

   http-observatory - Mozilla HTTP Observatory cli version.

   Hurl - is a command line tool to run and test HTTP requests with plain text.

##### :black_small_square: SSL


   openssl - is a robust, commercial-grade, and full-featured toolkit for the TLS and SSL protocols.

   gnutls-cli - client program to set up a TLS connection to some other computer.

   sslyze
- fast and powerful SSL/TLS server scanning library.

   sslscan - tests SSL/TLS enabled services to discover supported cipher suites.

   testssl.sh - testing TLS/SSL encryption anywhere on any port.

   cipherscan - a very simple way to find out which SSL ciphersuites are supported by a target.

   spiped - is a utility for creating symmetrically encrypted and authenticated pipes between socket addresses.

   Certbot - is EFF's tool to obtain certs from Let's Encrypt and (optionally) auto-enable HTTPS on your server.

   mkcert - simple zero-config tool to make locally trusted development certificates with any names you'd like.

   certstrap - tools to bootstrap CAs, certificate requests, and signed certificates.

   Sublert - is a security and reconnaissance tool to automatically monitor new subdomains.

   mkchain - open source tool to help you build a valid SSL certificate chain.

   ssl-cert-check - SSL Certification Expiration Checker.

##### :black_small_square: Security


   SELinux - provides a flexible Mandatory Access Control (MAC) system built into the Linux kernel.

   AppArmor - proactively protects the operating system and applications from external or internal threats.

   grapheneX - Automated System Hardening Framework.

   DevSec Hardening Framework - Security + DevOps: Automatic Server Hardening.

##### :black_small_square: Auditing Tools


   ossec - actively monitoring all aspects of system activity with file integrity monitoring.

   auditd - provides a way to track security-relevant information on your system.

   Tiger - is a security tool that can be use both as a security audit and intrusion detection system.

   Lynis - battle-tested security tool for systems running Linux, macOS, or Unix-based operating system.

   LinEnum - scripted Local Linux Enumeration & Privilege Escalation Checks.

   Rkhunter - scanner tool for Linux systems that scans backdoors, rootkits and local exploits on your systems.

   PE-sieve - is a light-weight tool that helps to detect malware running on the system.

   PEASS - privilege escalation tools for Windows and Linux/Unix and MacOS.

##### :black_small_square: System Diagnostics/Debuggers


   strace - diagnostic, debugging and instructional userspace utility for Linux.

   DTrace - is a performance analysis and troubleshooting tool.

   ltrace - is a library call tracer, used to trace calls made by programs to library functions.

   ptrace-burrito - is a friendly wrapper around ptrace.

   perf-tools - performance analysis tools based on Linux perf_events (aka perf) and ftrace.

   bpftrace - high-level tracing language for Linux eBPF.

   sysdig - system exploration and troubleshooting tool with first class support for containers.

   Valgrind - is an instrumentation framework for building dynamic analysis tools.

   gperftools - high-performance multi-threaded malloc() implementation, plus some performance analysis tools.

   glances - cross-platform system monitoring tool written in Python.

   htop - interactive text-mode process viewer for Unix systems. It aims to be a better 'top'.

   bashtop - Linux resource monitor written in pure Bash.

   nmon - a single executable for performance monitoring and data analysis.

   atop - ASCII performance monitor. Includes statistics for CPU, memory, disk, swap, network, and processes.

   lsof - displays in its output information about files that are opened by processes.

   FlameGraph - stack trace visualizer.

   lsofgraph - convert Unix lsof output to a graph showing FIFO and UNIX interprocess communication.

   rr - is a lightweight tool for recording, replaying and debugging execution of applications.

   Performance Co-Pilot - a system performance analysis toolkit.

   hexyl - a command-line hex viewer.

   Austin - Python frame stack sampler for CPython.

##### :black_small_square: Log Analyzers


   angle-grinder - slice and dice log files on the command line.

   lnav - log file navigator with search and automatic refresh.

   GoAccess - real-time web log analyzer and interactive viewer that runs in a terminal.

   ngxtop - real-time metrics for nginx server.

##### :black_small_square: Databases


   usql - universal command-line interface for SQL databases.

   pgcli - postgres CLI with autocompletion and syntax highlighting.

   mycli - terminal client for MySQL with autocompletion and syntax highlighting.

   litecli - SQLite CLI with autocompletion and syntax highlighting.

   mssql-cli - SQL Server CLI with autocompletion and syntax highlighting.

   OSQuery - is a SQL powered operating system instrumentation, monitoring, and analytics framework.

   pgsync - sync data from one Postgres database to another.

   iredis - a terminal client for redis with autocompletion and syntax highlighting.

   SchemaCrawler - generates an E-R diagram of your database.

##### :black_small_square: TOR


   Nipe - script to make Tor Network your default gateway.

   multitor - a tool that lets you create multiple TOR instances with a load-balancing.

##### :black_small_square: Messengers/IRC Clients


   Irssi - is a free open source terminal based IRC client.

   WeeChat - is an extremely extensible and lightweight IRC client.

##### :black_small_square: Productivity


   taskwarrior - task management system, todo list

##### :black_small_square: Other


   sysadmin-util - tools for Linux/Unix sysadmins.

   incron - is an inode-based filesystem notification technology.

   lsyncd - synchronizes local directories with remote targets (Live Syncing Daemon).

   GRV - is a terminal based interface for viewing Git repositories.

   Tig - text-mode interface for Git.

   tldr - simplified and community-driven man pages.

   archiver - easily create and extract .zip, .tar, .tar.gz, .tar.bz2, .tar.xz, .tar.lz4, .tar.sz, and .rar.

   commander.js - minimal CLI creator in JavaScript.

   gron - make JSON greppable!

   bed - binary editor written in Go.

#### GUI Tools  [[TOC]](#anger-table-of-contents)

##### :black_small_square: Terminal emulators


   Guake - is a dropdown terminal made for the GNOME desktop environment.

   Terminator - is based on GNOME Terminal, useful features for sysadmins and other users.

   Kitty - is a GPU based terminal emulator that supports smooth scrolling and images.

   Alacritty - is a fast, cross-platform, OpenGL terminal emulator.

##### :black_small_square: Network


   Wireshark - is the world’s foremost and widely-used network protocol analyzer.

   Ettercap - is a comprehensive network monitor tool.

   EtherApe - is a graphical network monitoring solution.

   Packet Sender - is a networking utility for packet generation and built-in UDP/TCP/SSL client and servers.

   Ostinato - is a packet crafter and traffic generator.

   JMeter™ - open source software to load test functional behavior and measure performance.

   locust - scalable user load testing tool written in Python.

##### :black_small_square: Browsers


   TOR Browser - protect your privacy and defend yourself against network surveillance and traffic analysis.

##### :black_small_square: Password Managers


   KeePassXC - store your passwords safely and auto-type them into your everyday websites and apps.

   Bitwarden - open source password manager with built-in sync.

   Vaultwarden - unofficial Bitwarden compatible server written in Rust.

##### :black_small_square: Messengers/IRC Clients


   HexChat - is an IRC client based on XChat.

   Pidgin - is an easy to use and free chat client used by millions.

##### :black_small_square: Messengers (end-to-end encryption)


   Signal - is an encrypted communications app.

   Wire - secure messaging, file sharing, voice calls and video conferences.

   TorChat - decentralized anonymous instant messenger on top of Tor Hidden Services.

   Matrix - an open network for secure, decentralized, real-time communication.

##### :black_small_square: Text editors


   Sublime Text - is a lightweight, cross-platform code editor known for its speed, ease of use.

   Visual Studio Code - an open-source and free source code editor developed by Microsoft.

   Atom - a hackable text editor for the 21st Century.

#### Web Tools  [[TOC]](#anger-table-of-contents)

##### :black_small_square: Browsers


   SSL/TLS Capabilities of Your Browser - test your browser's SSL implementation.

   Can I use - provides up-to-date browser support tables for support of front-end web technologies.

   Panopticlick 3.0 - is your browser safe against tracking?

   Privacy Analyzer - see what data is exposed from your browser.

   Web Browser Security - it's all about Web Browser fingerprinting.

   How's My SSL? - help a web server developer learn what real world TLS clients were capable of.

   sslClientInfo - client test (incl TLSv1.3 information).

##### :black_small_square: SSL/Security


   SSLLabs Server Test - performs a deep analysis of the configuration of any SSL web server.

   SSLLabs Server Test (DEV) - performs a deep analysis of the configuration of any SSL web server.

   ImmuniWeb® SSLScan - test SSL/TLS (PCI DSS, HIPAA and NIST).

   SSL Check - scan your website for non-secure content.

   SSL Scanner - analyze website security.

   CryptCheck - test your TLS server configuration (e.g. ciphers).

   urlscan.io - service to scan and analyse websites.

   Report URI - monitoring security policies like CSP and HPKP.

   CSP Evaluator - allows developers and security experts to check if a Content Security Policy.

   Useless CSP - public list about CSP in some big players (might make them care a bit more).

   Why No HTTPS? - top 100 websites by Alexa rank not automatically redirecting insecure requests.

   TLS Cipher Suite Search- cipher suite search engine.

   cipherli.st - strong ciphers for Apache, Nginx, Lighttpd, and more.*

   dhtool - public Diffie-Hellman parameter service/tool.

   badssl.com - memorable site for testing clients against bad SSL configs.

   tlsfun.de - registered for various tests regarding the TLS/SSL protocol.

   CAA Record Helper - generate a CAA policy.

   Common CA Database - repository of information about CAs, and their root and intermediate certificates.

   CERTSTREAM - real-time certificate transparency log update stream.

   crt.sh - discovers certificates by continually monitoring all of the publicly known CT.

   Hardenize - deploy the security standards.

   Cipher suite compatibility - test TLS cipher suite compatibility.

   urlvoid - this service helps you detect potentially malicious websites.

   security.txt - a proposed standard (generator) which allows websites to define security policies.

   ssl-config-generator - help you follow the Mozilla Server Side TLS configuration guidelines.

   TLScan - pure python, SSL/TLS protocol and cipher scanner/enumerator.

##### :black_small_square: HTTP Headers & Web Linters


   Security Headers - analyse the HTTP response headers (with rating system to the results).

   Observatory by Mozilla - set of tools to analyze your website.

   webhint - is a linting tool that will help you with your site's accessibility, speed, security, and more.

##### :black_small_square: DNS


   ViewDNS - one source for free DNS related tools and information.

   DNSLookup - is an advanced DNS lookup tool.

   DNSlytics - online DNS investigation tool.

   DNS Spy - monitor, validate and verify your DNS configurations.

   Zonemaster - helps you to control how your DNS works.

   Leaf DNS - comprehensive DNS tester.

   Find subdomains online - find subdomains for security assessment penetration test.

   DNSdumpster - dns recon & research, find & lookup dns records.

   DNS Table online - search for DNS records by domain, IP, CIDR, ISP.

   intoDNS - DNS and mail server health checker.

   DNS Bajaj - check the delegation of your domain.

   BuddyDNS Delegation LAB - check, trace and visualize delegation of your domain.

   dnssec-debugger - DS or DNSKEY records validator.

   PTRarchive.com - this site is responsible for the safekeeping of historical reverse DNS records.

   xip.io - wildcard DNS for everyone.

   nip.io - dead simple wildcard DNS for any IP Address.

   dnslookup (ceipam) - one of the best DNS propagation checker (and not only).

   What's My DNS - DNS propagation checking tool.

   DNSGrep - quickly searching large DNS datasets.

##### :black_small_square: Mail


   smtp-tls-checker - check an email domain for SMTP TLS support.

   MX Toolbox - all of your MX record, DNS, blacklist and SMTP diagnostics in one integrated tool.

   Secure Email - complete email test tools for email technicians.

   blacklistalert - checks to see if your domain is on a Real Time Spam Blacklist.

   MultiRBL - complete IP check for sending Mailservers.

   DKIM SPF & Spam Assassin Validator - checks mail authentication and scores messages with Spam Assassin.

##### :black_small_square: Encoders/Decoders and Regex testing


   URL Encode/Decode - tool from above to either encode or decode a string of text.

   Uncoder - the online translator for search queries on log data.

   Regex101 - online regex tester and debugger: PHP, PCRE, Python, Golang and JavaScript.

   RegExr - online tool to learn, build, & test Regular Expressions (RegEx / RegExp).

   RegEx Testing - online regex testing tool.

   RegEx Pal - online regex testing tool + other tools.

   The Cyber Swiss Army Knife - a web app for encryption, encoding, compression and data analysis.

##### :black_small_square: Net-tools


   Netcraft - detailed report about the site, helping you to make informed choices about their integrity.*

   RIPE NCC Atlas - a global, open, distributed Internet measurement platform.

   Robtex - uses various sources to gather public information about IP numbers, domain names, host names, etc.

   Security Trails - APIs for Security Companies, Researchers and Teams.

   Online Curl - curl test, analyze HTTP Response Headers.

   Online Tools for Developers - HTTP API tools, testers, encoders, converters, formatters, and other tools.

   Ping.eu - online Ping, Traceroute, DNS lookup, WHOIS and others.

   Network-Tools - network tools for webmasters, IT technicians & geeks.

   BGPview - search for any ASN, IP, Prefix or Resource name.

   Is BGP safe yet? - check BGP (RPKI) security of ISPs and other major Internet players.

   Riseup - provides online communication tools for people and groups working on liberatory social change.

   VirusTotal - analyze suspicious files and URLs to detect types of malware.

##### :black_small_square: Privacy


   privacyguides.org - provides knowledge and tools to protect your privacy against global mass surveillance.

   DNS Privacy Test Servers - DNS privacy recursive servers list (with a 'no logging' policy).

##### :black_small_square: Code parsers/playgrounds


   ShellCheck - finds bugs in your shell scripts.

   explainshell - get interactive help texts for shell commands.

   jsbin - live pastebin for HTML, CSS & JavaScript, and more.

   CodeSandbox - online code editor for web application development.

   PHP Sandbox - test your PHP code with this code tester.

   Repl.it - an instant IDE to learn, build, collaborate, and host all in one place.

   vclFiddle - is an online tool for experimenting with the Varnish Cache VCL.

   Haskell Dockerfile Linter - a smarter Dockerfile linter that helps you build best practice Docker images.

##### :black_small_square: Performance


   GTmetrix - analyze your site’s speed and make it faster.

   Sucuri loadtimetester - test here the
performance of any of your sites from across the globe.

   Pingdom Tools - analyze your site’s speed around the world.

   PingMe.io - run website latency tests across multiple geographic regions.

   PageSpeed Insights - analyze your site’s speed and make it faster.

   web.dev - helps developers like you learn and apply the web's modern capabilities to your own sites and apps.

   Lighthouse - automated auditing, performance metrics, and best practices for the web.

##### :black_small_square: Mass scanners (search engines)


   Censys - platform that helps information security practitioners discover, monitor, and analyze devices.

   Shodan - the world's first search engine for Internet-connected devices.

   Shodan 2000 - this tool looks for randomly generated data from Shodan.

   GreyNoise - mass scanner such as Shodan and Censys.

   ZoomEye - search engine for cyberspace that lets the user find specific network components.

   netograph - tools to monitor and understand deep structure of the web.

   FOFA - is a cyberspace search engine.

   onyphe - is a search engine for open-source and cyber threat intelligence data collected.

   IntelligenceX - is a search engine and data archive.

   binaryedge - it scan the entire internet space and create real-time threat intelligence streams and reports.

   Spyse - Internet assets registry: networks, threats, web objects, etc.

   wigle - is a submission-based catalog of wireless networks. All the networks. Found by Everyone.

   PublicWWW - find any alphanumeric snippet, signature or keyword in the web pages HTML, JS and CSS code.

   IntelTechniques - this repository contains hundreds of online search utilities.

   hunter - lets you find email addresses in seconds and connect with the people that matter for your business.

   GhostProject? - search by full email address or username.

   databreaches - was my email affected by data breach?

   We Leak Info - world's fastest and largest data breach search engine.

   Pulsedive - scans of malicious URLs, IPs, and domains, including port scans and web requests.

   Buckets by Grayhatwarfar - database with public search for Open Amazon S3 Buckets and their contents.

   Vigilante.pw - the breached database directory.

   builtwith - find out what websites are built with.

   NerdyData - search the web's source code for technologies, across millions of sites.

   zorexeye - search for sites, images, apps, softwares & more.

   Mamont's open FTP Index - if a target has an open FTP site with accessible content it will be listed here.

   OSINT Framework - focused on gathering information from free tools or resources.

   maltiverse - is a service oriented to cybersecurity analysts.

   Leaked Source - is a collaboration of data found online in the form of a lookup.

   We Leak Info - to help everyday individuals secure their online life, avoiding getting hacked.

   pipl - is the place to find the person behind the email address, social username or phone number.

   abuse.ch - is operated by a random swiss guy fighting malware for non-profit.

   malc0de - malware search engine.

   Cybercrime Tracker - monitors and tracks various malware families that are used to perpetrate cyber crimes.

   shhgit - find GitHub secrets in real time.

   searchcode - helping you find real world examples of functions, API's and libraries.

   Insecam - the world biggest directory of online surveillance security cameras.

   index-of - contains great stuff like: security, hacking, reverse engineering, cryptography, programming etc.

   Rapid7 Labs Open Data - is a great resources of datasets from Project Sonar.

   Common Response Headers - the largest database of HTTP response headers.

   InQuest Labs - InQuest Labs is an open, interactive, and API driven data portal for security researchers.

##### :black_small_square: Generators


   thispersondoesnotexist - generate fake faces in one click - endless possibilities.

   AI Generated Photos - 100.000 AI generated faces.

   fakenamegenerator - your randomly generated identity.

   Intigriti Redirector - open redirect/SSRF payload generator.

##### :black_small_square: Passwords


   have i been pwned? - check if you have an account that has been compromised in a data breach.

   dehashed - is a hacked database search engine.

   Leaked Source - is a collaboration of data found online in the form of a lookup.

##### :black_small_square: CVE/Exploits databases


   CVE Mitre - list of publicly known cybersecurity vulnerabilities.

   CVE Details - CVE security vulnerability advanced database.

   Exploit DB - CVE compliant archive of public exploits and corresponding vulnerable software.

   0day.today - exploits market provides you the possibility to buy/sell zero-day exploits.

   sploitus - the exploit and tools database.

   cxsecurity - free vulnerability database.

   Vulncode-DB - is a database for vulnerabilities and their corresponding source code if available.

   cveapi - free API for CVE data.

##### :black_small_square: Mobile apps scanners


   ImmuniWeb® Mobile App Scanner - test security and privacy of mobile apps (iOS & Android).

   Quixxi - free Mobile App Vulnerability Scanner for Android & iOS.

   Ostorlab - analyzes mobile application to identify vulnerabilities and potential weaknesses.

##### :black_small_square: Private Search Engines


   Startpage - the world's most private search engine.

   searX - a privacy-respecting, hackable metasearch engine.

   darksearch - the 1st real Dark Web search engine.

   Qwant - the search engine that respects your privacy.

   DuckDuckGo - the search engine that doesn't track you.

   Swisscows - privacy safe web search

   Disconnect - the search engine that anonymizes your searches.

   MetaGer - the search engine that uses anonymous proxy and hidden Tor branches.

##### :black_small_square: Secure Webmail Providers


   CounterMail - online email service, designed to provide maximum security and privacy.

   Mail2Tor - is a Tor Hidden Service that allows anyone to send and receive emails anonymously.

   Tutanota - is the world's most secure email service and amazingly easy to use.

   Protonmail - is the world's largest secure email service, developed by CERN and MIT scientists.

   Startmail - private & encrypted email made easy.

##### :black_small_square: Crypto


   Keybase - it's open source and powered by public-key cryptography.

##### :black_small_square: PGP Keyservers


   SKS OpenPGP Key server - services for the SKS keyservers used by OpenPGP.

#### Systems/Services  [[TOC]](#anger-table-of-contents)

##### :black_small_square: Operating Systems


   Slackware - the most "Unix-like" Linux distribution.

   OpenBSD - multi-platform 4.4BSD-based UNIX-like operating system.

   HardenedBSD - HardenedBSD aims to implement innovative exploit mitigation and security solutions.

   Kali Linux - Linux distribution used for Penetration Testing, Ethical Hacking and network security assessments.

   Parrot Security OS - cyber security GNU/Linux environment.

   Backbox Linux - penetration test and security assessment oriented Ubuntu-based Linux distribution.

   BlackArch - is an Arch Linux-based penetration testing distribution for penetration testers.

   Pentoo - is a security-focused livecd based on Gentoo.

   Security Onion - Linux distro for intrusion detection, enterprise security monitoring, and log management.

   Tails - is a live system that aims to preserve your privacy and anonymity.

   vedetta - OpenBSD router boilerplate.

   Qubes OS - is a security-oriented OS that uses Xen-based virtualization.

##### :black_small_square: HTTP(s) Services


   Varnish Cache - HTTP accelerator designed for content-heavy dynamic web sites.

   Nginx - open source web and reverse proxy server that is similar to Apache, but very light weight.

   OpenResty - is a dynamic web platform based on NGINX and LuaJIT.

   Tengine - a distribution of Nginx with some advanced features.

   Caddy Server - is an open source, HTTP/2-enabled web server with HTTPS by default.

   HAProxy - the reliable, high performance TCP/HTTP load balancer.

##### :black_small_square: DNS Services


   Unbound - validating, recursive, and caching DNS resolver (with TLS).

   Knot Resolver - caching full resolver implementation, including both a resolver library and a daemon.

   PowerDNS - is an open source authoritative DNS server, written in C++ and licensed under the GPL.

##### :black_small_square: Other Services


   3proxy - tiny free proxy server.

##### :black_small_square: Security/hardening


   Emerald Onion - is a 501(c)(3) nonprofit organization and transit internet service provider (ISP).

   pi-hole - the Pi-hole® is a DNS sinkhole that protects your devices from unwanted content.

   maltrail - malicious traffic detection system.

   security_monkey - monitors AWS, GCP, OpenStack, and GitHub orgs for assets and their changes over time.

   firecracker - secure and fast microVMs for serverless computing.

   streisand - sets up a new server running your choice of WireGuard, OpenSSH, OpenVPN, and more.

#### Networks  [[TOC]](#anger-table-of-contents)

##### :black_small_square: Tools


   CapAnalysis - web visual tool to analyze large amounts of captured network traffic (PCAP analyzer).

   netbox - IP address management (IPAM) and data center infrastructure management (DCIM) tool.

##### :black_small_square: Labs


   NRE Labs - learn automation by doing it. Right now, right here, in your browser.

##### :black_small_square: Other


   LBNL's Network Research Group - home page of the Network Research Group (NRG).

#### Containers/Orchestration  [[TOC]](#anger-table-of-contents)

##### :black_small_square: CLI Tools


   gvisor - container runtime sandbox.

   ctop - top-like interface for container metrics.

##### :black_small_square: Web Tools


   Moby - a collaborative project for the container ecosystem to assemble container-based system.

   Traefik - open source reverse proxy/load balancer provides easier integration with Docker and Let's encrypt.

   kong - The Cloud-Native API Gateway.

   rancher - complete container management platform.

   portainer - making Docker management easy.

   nginx-proxy - automated nginx proxy for Docker containers using docker-gen.

   bunkerized-nginx - nginx docker image "secure by default".

##### :black_small_square: Security


   docker-bench-security - checks for dozens of common best-practices around deploying Docker.

   trivy - vulnerability scanner for containers, suitable for CI.

   Harbor - cloud native registry project that stores, signs, and scans content.

   Houdini - hundreds of offensive and useful docker images for network intrusion.

##### :black_small_square: Manuals/Tutorials/Best Practices


   docker-cheat-sheet - a quick reference cheat sheet on Docker.

   awesome-docker - a curated list of Docker resources and projects.

   docker_practice - learn and understand Docker technologies, with real DevOps practice!

   labs
- is a collection of tutorials for learning how to use Docker with various tools.

   dockerfiles - various Dockerfiles I use on the desktop and on servers.

   kubernetes-the-hard-way - bootstrap Kubernetes the hard way on Google Cloud Platform. No scripts.

   kubernetes-the-easy-way - bootstrap Kubernetes the easy way on Google Cloud Platform. No scripts.

   cheatsheet-kubernetes-A4 - Kubernetes CheatSheets in A4.

   k8s-security - kubernetes security notes and best practices.

   kubernetes-production-best-practices - checklists with best-practices for production-ready Kubernetes.

   kubernetes-production-best-practices - kubernetes security - best practice guide.

   kubernetes-failure-stories - is a compilation of public failure/horror stories related to Kubernetes.

#### Manuals/Howtos/Tutorials  [[TOC]](#anger-table-of-contents)

##### :black_small_square: Shell/Command line


   pure-bash-bible - is a collection of pure bash alternatives to external processes.

   pure-sh-bible - is a collection of pure POSIX sh alternatives to external processes.

   bash-guide - is a guide to learn bash.

   bash-handbook - for those who wanna learn Bash.

   The Bash Hackers Wiki - hold documentation of any kind about GNU Bash.

   Shell & Utilities - describes the commands offered to application programs by POSIX-conformant systems.

   the-art-of-command-line - master the command line, in one page.

   Shell Style Guide - a shell style guide for Google-originated open-source projects.

##### :black_small_square: Text Editors


   Vim Cheat Sheet - great multi language vim guide.

##### :black_small_square: Python


   Awesome Python - a curated list of awesome Python frameworks, libraries, software and resources.

   python-cheatsheet - comprehensive Python cheatsheet.

   pythoncheatsheet.org - basic reference for beginner and advanced developers.

##### :black_small_square: Sed & Awk & Other


   F’Awk Yeah! - advanced sed and awk usage (Parsing for Pentesters 3).

##### :black_small_square: \*nix & Network


   nixCraft - linux and unix tutorials for new and seasoned sysadmin.

   TecMint - the ideal Linux blog for Sysadmins & Geeks.

   Omnisecu - free Networking, System Administration and Security tutorials.

   linux-cheat - Linux tutorials and cheatsheets. Minimal examples. Mostly user-land CLI utilities.

   linuxupskillchallenge - learn the skills required to sysadmin.

   Unix Toolbox - Unix/Linux/BSD commands and tasks which are useful for IT work or for advanced users.

   Linux Kernel Teaching - is a collection of lectures and labs Linux kernel topics.

   htop explained - explanation of everything you can see in htop/top on Linux.

   Linux Guide and Hints - tutorials on system administration in Fedora and CentOS.

   strace-little-book - a little book which introduces strace.

   linux-tracing-workshop - examples and hands-on labs for Linux tracing tools workshops.

   http2-explained - a detailed document explaining and documenting HTTP/2.

   http3-explained - a document describing the HTTP/3 and QUIC protocols.

   HTTP/2 in Action - an excellent introduction to the new HTTP/2 standard.

   Let's code a TCP/IP stack - great stuff to learn network and system programming at a deeper level.

   Nginx Admin's Handbook - how to improve NGINX performance, security and other important things.

   nginxconfig.io - NGINX config generator on steroids.

   openssh guideline - is to help operational teams with the configuration of OpenSSH server and client.

   SSH Handshake Explained - is a relatively brief description of the SSH handshake.

   ISC's Knowledgebase - you'll find some general information about BIND 9, ISC DHCP, and Kea DHCP.

   PacketLife.net - a place to record notes while studying for Cisco's CCNP certification.

##### :black_small_square: Microsoft


   AD-Attack-Defense - attack and defend active directory using modern post exploitation activity.

##### :black_small_square: Large-scale systems


   The System Design Primer - learn how to design large-scale systems.

   Awesome Scalability - best practices in building High Scalability, High Availability, High Stability, and more.

   Web Architecture 101 - the basic architecture concepts.

##### :black_small_square: System hardening


   CIS Benchmarks - secure configuration settings for over 100 technologies, available as a free PDF.

   Security Harden CentOS 7 - this walks you through the steps required to security harden CentOS.

   CentOS 7 Server Hardening Guide - great guide for hardening CentOS; familiar with OpenSCAP.

   awesome-security-hardening - is a collection of security hardening guides, tools and other resources.

   The Practical Linux Hardening Guide - provides a high-level overview of hardening GNU/Linux systems.

   Linux Hardening Guide - how to harden Linux as much as possible for security and privacy.

##### :black_small_square: Security & Privacy


   Hacking Articles - LRaj Chandel's Security & Hacking Blog.

   AWS security tools - make your AWS cloud environment more secure.

   Rawsec's CyberSecurity Inventory - an inventory of tools and resources about CyberSecurity.

   The Illustrated TLS Connection - every byte of a TLS connection explained and reproduced.

   SSL Research - SSL and TLS Deployment Best Practices by SSL Labs.

   SELinux Game - learn SELinux by doing. Solve Puzzles, show skillz.

   Certificates and PKI - everything you should know about certificates and PKI but are too afraid to ask.

   The Art of Subdomain Enumeration - a reference for subdomain enumeration techniques.

   Quitting Google - the comprehensive guide to quitting Google.

##### :black_small_square: Web Apps


   OWASP - worldwide not-for-profit charitable organization focused on improving the security of software.

   OWASP ASVS 3.0.1 - OWASP Application Security Verification Standard Project.

   OWASP ASVS 3.0.1 Web App - simple web app that helps developers understand the ASVS requirements.

   OWASP ASVS 4.0 - is a list of application security requirements or tests.

   OWASP Testing Guide v4 - includes a "best practice" penetration testing framework.

   OWASP Dev Guide - this is the development version of the OWASP Developer Guide.

   OWASP WSTG - is a comprehensive open source guide to testing the security of web apps.

   OWASP API Security Project - focuses specifically on the top ten vulnerabilities in API security.

   Mozilla Web Security - help operational teams with creating secure web applications.

   security-bulletins - security bulletins that relate to Netflix Open Source.

   API-Security-Checklist - security countermeasures when designing, testing, and releasing your API.

   Enable CORS - enable cross-origin resource sharing.

   Application Security Wiki - is an initiative to provide all application security related resources at one place.

   Weird Proxies - reverse proxy related attacks; it is a result of analysis of various proxies.

   Webshells - great series about malicious payloads.

   Practical Web Cache Poisoning - show you how to compromise websites by using esoteric web features.

   Hidden directories and files - as a source of sensitive information about web application.

   Explosive blog - great blog about cybersec and pentests.

   Security Cookies - this paper will take a close look at cookie security.

   APISecurityBestPractices - help you keep secrets (API keys, db credentials, certificates) out of source code.

##### :black_small_square: All-in-one


   LZone Cheat Sheets - all cheat sheets.

   Dan’s Cheat Sheets’s - massive cheat sheets documentation.

   Rico's cheatsheets - this is a modest collection of cheatsheets.

   DevDocs API - combines multiple API documentations in a fast, organized, and searchable interface.

   cheat.sh - the only cheat sheet you need.

   gnulinux.guru - collection of cheat sheets about bash, vim and networking.

   Web Skills - visual overview of useful skills to learn as a web developer.

##### :black_small_square: Ebooks


   free-programming-books - list of free learning resources in many languages.

##### :black_small_square: Other


   CTF Series : Vulnerable Machines - the steps below could be followed to find vulnerabilities and exploits.

   50M_CTF_Writeup - $50 million CTF from Hackerone - writeup.

   ctf-tasks - an archive of low-level CTF challenges developed over the years.

   How to start RE/malware analysis? - collection of some hints and useful links for the beginners.

   The C10K problem - it's time for web servers to handle ten thousand clients simultaneously, don't you think?

   How 1500 bytes became the MTU of the internet - great story about the Maximum Transmission Unit.

   poor man's profiler - like dtrace's don't really provide methods to see what programs are blocking on.

   HTTPS on Stack Overflow - this is the story of a long journey regarding the implementation of SSL.

   Julia's Drawings - some drawings about programming and unix world, zines about systems & debugging tools.

   Hash collisions - this great repository is focused on hash collisions exploitation.

   sha256-animation - animation of the SHA-256 hash function in your terminal.

   sha256algorithm - sha256 algorithm explained online step by step visually.

   BGP Meets Cat - after 3072 hours of manipulating BGP, Job Snijders has succeeded in drawing a Nyancat.

   bgp-battleships - playing battleships over BGP.

   What happens when... - you type google.com into your browser and press enter?

   how-web-works - based on the 'What happens when...' repository.

   HTTPS in the real world - great tutorial explain how HTTPS works in the real world.

   Gitlab and NFS bug - how we spent two weeks hunting an NFS bug in the Linux kernel.

   Gitlab melts down - postmortem on the database outage of January 31 2017 with the lessons we learned.

   How To Become A Hacker - if you want to be a hacker, keep reading.

   Operation Costs in CPU - should help to estimate costs of certain operations in CPU clocks.

   Let's Build a Simple Database - writing a sqlite clone from scratch in C.

   simple-computer - great resource to understand how computers work under the hood.

   The story of "Have I been pwned?" - working with 154 million records on Azure Table Storage.

   TOP500 Supercomputers - shows the 500 most powerful commercially available computer systems.

   How to build a 8 GPU password cracker - hours of frustration like desktop components do.

   CERN Data Centre - 3D visualizations of the CERN computing environments (and more).

   How fucked is my database - evaluate how fucked your database is with this handy website.

   Linux Troubleshooting 101 , 2016 Edition - everything is a DNS Problem...

   Five Whys - you know what the problem is, but you cannot solve it?

   Maersk, me & notPetya - how did ransomware successfully hijack hundreds of domain controllers?

   howhttps.works - how HTTPS works ...in a comic!

   howdns.works - a fun and colorful explanation of how DNS works.

   POSTGRESQLCO.NF - your postgresql.conf documentation and recommendations.

#### Inspiring Lists  [[TOC]](#anger-table-of-contents)

##### :black_small_square: SysOps/DevOps


   Awesome Sysadmin - amazingly awesome open source sysadmin resources.

   Awesome Shell - awesome command-line frameworks, toolkits, guides and gizmos.

   Command-line-text-processing - finding text to search and replace, sorting to beautifying, and more.

   Awesome Pcaptools - collection of tools developed by other researchers to process network traces.

   awesome-ebpf - a curated list of awesome projects related to eBPF.

   Linux Network Performance - where some of the network sysctl variables fit into the Linux/Kernel network flow.

   Awesome Postgres - list of awesome PostgreSQL software, libraries, tools and resources.

   quick-SQL-cheatsheet - a quick reminder of all SQL queries and examples on how to use them.

   Awesome-Selfhosted - list of Free Software network services and web applications which can be hosted locally.

   List of applications - huge list of apps sorted by category, as a reference for those looking for packages.

   CS-Interview-Knowledge-Map - build the best interview map.

   DevOps-Guide - DevOps Guide from basic to advanced with Interview Questions and Notes.

   FreeBSD Journal - it is a great list of periodical magazines about FreeBSD and other important things.

   devops-interview-questions - contains interview questions on various DevOps and SRE related topics.

##### :black_small_square: Developers


   Web Developer Roadmap - roadmaps, articles and resources to help you choose your path, learn and improve.

   Front-End-Checklist - the perfect Front-End Checklist for modern websites and meticulous developers.

   Front-End-Performance-Checklist - Front-End Performance Checklist that runs faster than the others.

   Python's Magic Methods - what are magic methods? They're everything in object-oriented Python.

   wtfpython - a collection of surprising Python snippets and lesser-known features.

   js-dev-reads - a list of books and articles for the discerning web developer to read.

   Commit messages guide - a guide to understand the importance of commit messages.

##### :black_small_square: Security/Pentesting


   Awesome Web Security - a curated list of Web Security materials and resources.

   awesome-cyber-skills - a curated list of hacking environments where you can train your cyber skills.

   awesome-devsecops - an authoritative list of awesome devsecops tools.

   awesome-osint - is a curated list of amazingly awesome OSINT.

   HolyTips - tips and tutorials on Bug Bounty Hunting and Web App Security.

   awesome-threat-intelligence - a curated list of Awesome Threat Intelligence resources.

   Red-Teaming-Toolkit - a collection of open source and commercial tools that aid in red team operations.

   awesome-burp-extensions - a curated list of amazingly awesome Burp Extensions.

   Free Security eBooks - list of a Free Security and Hacking eBooks.

   Hacking-Security-Ebooks - top 100 Hacking & Security E-Books.

   privacy-respecting - curated list of privacy respecting services and software.

   reverse-engineering - list of awesome reverse engineering resources.

   linux-re-101 - a collection of resources for linux reverse engineering.

   reverseengineering-reading-list - a list of Reverse Engineering articles, books, and papers.

   Awesome-WAF - a curated list of awesome web-app firewall (WAF) stuff.

   awesome-shodan-queries - interesting, funny, and depressing search queries to plug into shodan.io.

   RobotsDisallowed - a curated list of the most common and most interesting robots.txt disallowed directories.

   HackingNeuralNetworks - is a small course on exploiting and defending neural networks.

   wildcard-certificates - why you probably shouldn't use a wildcard certificate.

   Don't use VPN services - which is what every third-party "VPN provider" does.

   awesome-yara - a curated list of awesome YARA rules, tools, and people.

   macOS-Security-and-Privacy-Guide - guide to securing and improving privacy on macOS.

   macos_security - macOS Security Compliance Project.

   awesome-sec-talks - is a collected list of awesome security talks.

   Movies for Hackers - list of movies every hacker & cyberpunk must watch.

   Cryptography_1 - materials used whilst taking Prof. Dan Boneh Stanford Crypto course.

   Crypton - library to learn and practice Offensive and Defensive Cryptography.

##### :black_small_square: Other


   Cheatography - over 3,000 free cheat sheets, revision aids and quick references.

   awesome-static-analysis - static analysis tools for all programming languages.

   computer-science - path to a free self-taught education in Computer Science.

   post-mortems - is a collection of postmortems (config errors, hardware failures, and more).

   build-your-own-x - build your own (insert technology here).

   Project-Based-Tutorials-in-C - is a curated list of project-based tutorials in C.

   The-Documentation-Compendium - various README templates & tips on writing high-quality documentation.

   awesome-python-applications - free software that works great, and also happens to be open-source Python.

   awesome-public-datasets - a topic-centric list of HQ open datasets.

   machine-learning-algorithms - a curated list of all machine learning algorithms and concepts.

#### Blogs/Podcasts/Videos  [[TOC]](#anger-table-of-contents)

##### :black_small_square: SysOps/DevOps


   Varnish for PHP developers - very interesting presentation of Varnish by Mattias Geniar.

   A Netflix Guide to Microservices - talks about the chaotic and vibrant world of microservices at Netflix.

##### :black_small_square: Developers


   Comparing C to machine lang - compare a simple C app with the compiled machine code of that program.

##### :black_small_square: Geeky Persons


   Brendan Gregg's Blog - is an industry expert in computing performance and cloud computing.

   Gynvael "GynDream" Coldwind - is a IT security engineer at Google.

   Michał "lcamtuf" Zalewski - white hat hacker, computer security expert.

   Mattias Geniar - developer, sysadmin, blogger, podcaster and public speaker.

   Nick Craver - software developer and systems administrator for Stack Exchange.

   Scott Helme - security researcher, speaker and founder of securityheaders.com and report-uri.com.

   Brian Krebs - The Washington Post and now an Independent investigative journalist.

   Bruce Schneier - is an internationally renowned security technologist, called a "security guru".

   Chrissy Morgan - advocate of practical learning, Chrissy also takes part in bug bounty programs.

   Andy Gill - is a hacker at heart who works as a senior penetration tester.

   Daniel Miessler - cybersecurity expert and writer.

   Samy Kamkar - is an American privacy and security researcher, computer hacker.

   Javvad Malik - is a security advocate at AlienVault, a blogger event speaker and industry commentator.

   Graham Cluley - public speaker and independent computer security analyst.

   Kacper Szurek - detection engineer at ESET.

   Troy Hunt - web security expert known for public education and outreach on security topics.

   raymii.org - sysadmin specializing in building high availability cloud environments.

   Robert Penz - IT security expert.

##### :black_small_square: Geeky Blogs


   Linux Audit - the Linux security blog about auditing, hardening and compliance by Michael Boelen.

  
Linux Security Expert
- trainings, howtos, checklists, security tools, and more.

   The Grymoire - collection of useful incantations for wizards, be you computer wizards, magicians, or whatever.

   Secjuice - is the only non-profit, independent and volunteer led publication in the information security space.

   Decipher - security news that informs and inspires.

##### :black_small_square: Geeky Vendor Blogs


   Tenable Podcast - conversations and interviews related to Cyber Exposure, and more.

   Sophos - threat news room, giving you news, opinion, advice and research on computer security issues.

   Tripwire State of Security - blog featuring the latest news, trends and insights on current security issues.

   Malwarebytes Labs Blog - security blog aims to provide insider news about cybersecurity.

   TrustedSec - latest news, and trends about cybersecurity.

   PortSwigger Web Security Blog - about web app security vulns and top tips from our team of web security.

   AT&T Cybersecurity blog - news on emerging threats and practical advice to simplify threat detection.

   Thycotic - where CISOs and IT Admins come to learn about industry trends, IT security, and more.

##### :black_small_square: Geeky Cybersecurity Podcasts


   Risky Business - is a weekly information security podcast featuring news and in-depth interviews.

   Cyber, by Motherboard - stories, and focus on the ideas about cybersecurity.

   Tenable Podcast - conversations and interviews related to Cyber Exposure, and more.

  
Cybercrime Investigations
- podcast by Geoff White about cybercrimes.

   The many hats club - featuring stories from a wide range of Infosec people (Whitehat, Greyhat and Blackhat).

   Darknet Diaries - true stories from the dark side of the Internet.

   OSINTCurious Webcasts - is the investigative curiosity that helps people be successful in OSINT.

   Security Weekly - the latest information security and hacking news.

##### :black_small_square: Geeky Cybersecurity Video Blogs


   rev3rse security - offensive, binary exploitation, web app security, hardening, red team, blue team.

   LiveOverflow - a lot more advanced topics than what is typically offered in paid online courses - but for free.

   J4vv4D - the important information regarding our internet security.

  
CyberTalks
- talks, interviews, and article about cybersecurity.

##### :black_small_square: Best Personal Twitter Accounts


   @blackroomsec - a white-hat hacker/pentester. Intergalactic Minesweeper Champion 1990.

   @MarcoCiappelli - Co-Founder @ITSPmagazine, at the intersection of IT security and society.

   @binitamshah - Linux Evangelist. Malwares. Kernel Dev. Security Enthusiast.

   @joe_carson - an InfoSec Professional and Tech Geek.

   @mikko - CRO at F-Secure, Reverse Engineer, TED Speaker, Supervillain.

   @esrtweet - often referred to as ESR, is an American software developer, and open-source software advocate.

   @gynvael - security researcher/programmer, @DragonSectorCTF founder/player, technical streamer.

   @x0rz - Security Researcher & Cyber Observer.

   @hasherezade - programmer, malware analyst. Author of PEbear, PEsieve, libPeConv.

   @TinkerSec - tinkerer, cypherpunk, hacker.

   @alisaesage - independent hacker and researcher.

   @SwiftOnSecurity - systems security, industrial safety, sysadmin, author of decentsecurity.com.

   @dakami - is one of just seven people with the authority to restore the DNS root keys.

   @samykamkar - is a famous "grey hat" hacker, security researcher, creator of the MySpace "Samy" worm.

   @securityweekly - founder & CTO of Security Weekly podcast network.

   @jack_daniel - @SecurityBSides co-founder.

   @thegrugq - Security Researcher.

   @matthew_d_green - a cryptographer and professor at Johns Hopkins University.

##### :black_small_square: Best Commercial Twitter Accounts


   @haveibeenpwned - check if you have an account that has been compromised in a data breach.

   @bugcrowd - trusted by more of the Fortune 500 than any other crowdsourced security platform.

   @Malwarebytes - most trusted security company. Unmatched threat visibility.

   @sansforensics - the world's leading Digital Forensics and Incident Response provider.

   @attcyber - AT&T Cybersecurity’s Edge-to-Edge technologies provide threat intelligence, and more.

   @TheManyHatsClub - an information security focused podcast and group of individuals from all walks of life.

   @hedgehogsec - Hedgehog Cyber. Gibraltar and Manchester's top boutique information security firm.

   @NCSC - the National Cyber Security Centre. Helping to make the UK the safest place to live and work online.

   @Synacktiv - IT security experts.

##### :black_small_square: A piece of history


   How to Do Things at ARL - how to configure modems, scan images, record CD-ROMs, and other.*

##### :black_small_square: Other


   Diffie-Hellman Key Exchange (short version) - how Diffie-Hellman Key Exchange worked.

#### Hacking/Penetration Testing  [[TOC]](#anger-table-of-contents)

##### :black_small_square: Pentesters arsenal tools


   Sandcat Browser - a penetration-oriented browser with plenty of advanced functionality already built in.

   Metasploit - tool and framework for pentesting system, web and many more.

   Burp Suite - tool for testing web app security, intercepting proxy to replay, inject, scan and fuzz.

   OWASP Zed Attack Proxy - intercepting proxy to replay, inject, scan and fuzz HTTP requests.

   w3af - is a Web Application Attack and Audit Framework.

   mitmproxy - an interactive TLS-capable intercepting HTTP proxy for penetration testers.

   Nikto2 - web server scanner which performs comprehensive tests against web servers for multiple items.

   sqlmap - tool that automates the process of detecting and exploiting SQL injection flaws.

   Recon-ng - is a full-featured Web Reconnaissance framework written in Python.

   AutoRecon - is a network reconnaissance tool which performs automated enumeration of services.

   Faraday - an Integrated Multiuser Pentest Environment.

   Photon - incredibly fast crawler designed for OSINT.

   XSStrike - most advanced XSS detection suite.

   Sn1per - automated pentest framework for offensive security experts.

   vuls - is an agent-less vulnerability scanner for Linux, FreeBSD, and other.

   tsunami - is a general purpose network security scanner with an extensible plugin system.

   aquatone - a tool for domain flyovers.

   BillCipher - information gathering tool for a website or IP address.

   WhatWaf - detect and bypass web application firewalls and protection systems.

   Corsy - CORS misconfiguration scanner.

   Raccoon - is a high performance offensive security tool for reconnaissance and vulnerability scanning.

   dirhunt - find web directories without bruteforce.

   John The Ripper - is a fast password cracker, currently available for many flavors of Unix, Windows, and other.

   hashcat - world's fastest and most advanced password recovery utility.

   p0f - is a tool to identify the players behind any incidental TCP/IP communications.

   ssh_scan - a prototype SSH configuration and policy scanner.

   LeakLooker - find open databases - powered by Binaryedge.io

   exploitdb - searchable archive from The Exploit Database.

   getsploit - is a command line utility for searching and downloading exploits.

   ctf-tools - some setup scripts for security research tools.

   pwntools - CTF framework and exploit development library.

   security-tools - collection of small security tools created mostly in Python. CTFs, pentests and so on.

   pentestpackage - is a package of Pentest scripts.

   python-pentest-tools - python tools for penetration testers.

   fuzzdb - dictionary of attack patterns and primitives for black-box application fault injection.

   AFL - is a free software fuzzer maintained by Google.

   AFL++ - is AFL with community patches.

   syzkaller - is an unsupervised, coverage-guided kernel fuzzer.

   pwndbg - exploit development and reverse engineering with GDB made easy.

   GDB PEDA - Python Exploit Development Assistance for GDB.

   IDA - multi-processor disassembler and debugger useful for reverse engineering malware.

   radare2 - framework for reverse-engineering and analyzing binaries.

   routersploit - exploitation framework for embedded devices.

   Ghidra - is a software reverse engineering (SRE) framework.

   Cutter - is an SRE platform integrating Ghidra's decompiler.

   Vulnreport - open-source pentesting management and automation platform by Salesforce Product Security.

   Mentalist - is a graphical tool for custom wordlist generation.

   archerysec - vulnerability assessment and management helps to perform scans and manage vulnerabilities.

   Osmedeus - fully automated offensive security tool for reconnaissance and vulnerability scanning.

   beef - the browser exploitation framework project.

   AutoSploit - automated mass exploiter.

   SUDO_KILLER - is a tool to identify and exploit sudo rules' misconfigurations and vulnerabilities.

   yara - the pattern matching swiss knife.

   mimikatz - a little tool to play with Windows security.

   sherlock - hunt down social media accounts by username across social networks.

   OWASP Threat Dragon - is a tool used to create threat model diagrams and to record possible threats.

##### :black_small_square: Pentests bookmarks collection


   PTES - the penetration testing execution standard.

   Pentests MindMap - amazing mind map with vulnerable apps and systems.

   WebApps Security Tests MindMap - incredible mind map for WebApps security tests.

   Brute XSS - master the art of Cross Site Scripting.

   XSS cheat sheet - contains many vectors that can help you bypass WAFs and filters.

   Offensive Security Bookmarks - security bookmarks collection, all things that author need to pass OSCP.

   Awesome Pentest Cheat Sheets - collection of the cheat sheets useful for pentesting.

   Awesome Hacking by HackWithGithub - awesome lists for hackers, pentesters and security researchers.

   Awesome Hacking by carpedm20 - a curated list of awesome hacking tutorials, tools and resources.

   Awesome Hacking Resources - collection of hacking/penetration testing resources to make you better.

   Awesome Pentest - collection of awesome penetration testing resources, tools and other shiny things.

   Awesome-Hacking-Tools - is a curated list of awesome Hacking Tools.

   Hacking Cheat Sheet - author hacking and pentesting notes.

   blackhat-arsenal-tools - official Black Hat arsenal security tools repository.

   Penetration Testing and WebApp Cheat Sheets - the complete list of Infosec related cheat sheets.

   Cyber Security Resources - includes thousands of cybersecurity-related references and resources.

   Pentest Bookmarks - there are a LOT of pentesting blogs.

   Cheatsheet-God - Penetration Testing Reference Bank - OSCP/PTP & PTX Cheatsheet.

   ThreatHunter-Playbook - to aid the development of techniques and hypothesis for hunting campaigns.

   Beginner-Network-Pentesting - notes for beginner network pentesting course.

   OSCPRepo - is a list of resources that author have been gathering in preparation for the OSCP.

   PayloadsAllTheThings - a list of useful payloads and bypass for Web Application Security and Pentest/CTF.

   payloads - git all the Payloads! A collection of web attack payloads.

   command-injection-payload-list - command injection payload list.

   Awesome Shodan Search Queries - great search queries to plug into Shodan.

   AwesomeXSS - is a collection of Awesome XSS resources.

   php-webshells - common php webshells.

   Pentesting Tools Cheat Sheet - a quick reference high level overview for typical penetration testing.

   OWASP Cheat Sheet Series - is a collection of high value information on specific application security topics.

   OWASP dependency-check - is an open source solution the OWASP Top 10 2013 entry.

   OWASP ProActive Controls - OWASP Top 10 Proactive Controls 2018.

   PENTESTING-BIBLE - hacking & penetration testing & red team & cyber security resources.

   pentest-wiki - is a free online security knowledge library for pentesters/researchers.

   DEF CON Media Server - great stuff from DEFCON.

   Awesome Malware Analysis - a curated list of awesome malware analysis tools and resources.

   SQL Injection Cheat Sheet - detailed technical stuff about the many different variants of the SQL Injection.

   Entersoft Knowledge Base - great and detailed reference about vulnerabilities.

   HTML5 Security Cheatsheet - a collection of HTML5 related XSS attack vectors.

   XSS String Encoder - for generating XSS code to check your input validation filters against XSS.

   GTFOBins - list of Unix binaries that can be exploited by an attacker to bypass local security restrictions.

   Guifre Ruiz Notes - collection of security, system, network and pentest cheatsheets.

   SSRF Tips - a collection of SSRF Tips.

   shell-storm repo CTF - great archive of CTFs.

   ctf - CTF (Capture The Flag) writeups, code snippets, notes, scripts.

   My-CTF-Web-Challenges - collection of CTF Web challenges.

   MSTG - The Mobile Security Testing Guide (MSTG) is a comprehensive manual for mobile app security testing.

   Internal-Pentest-Playbook - notes on the most common things for an Internal Network Penetration Test.

   KeyHacks - shows quick ways in which API keys leaked by a bug bounty program can be checked.

   securitum/research - various Proof of Concepts of security research performed by Securitum.

   public-pentesting-reports - is a list of public pentest reports released by several consulting security groups.

   awesome-bug-bounty - is a comprehensive curated list of available Bug Bounty.

   bug-bounty-reference - is a list of bug bounty write-ups.

   Awesome-Bugbounty-Writeups - is a curated list of bugbounty writeups.

   Bug bounty writeups - list of bug bounty writeups (2012-2020).

   hackso.me - a great journey into security.

##### :black_small_square: Backdoors/exploits


   PHP-backdoors - a collection of PHP backdoors. For educational or testing purposes only.

##### :black_small_square: Wordlists and Weak passwords


   Weakpass - for any kind of bruteforce find wordlists or unleash the power of them all at once!

   Hashes.org - is a free online hash resolving service incorporating many unparalleled techniques.

   SecLists - collection of multiple types of lists used during security assessments, collected in one place.

   Probable-Wordlists - sorted by probability originally created for password generation and testing.

   skullsecurity passwords - password dictionaries and leaked passwords repository.

   Polish PREMIUM Dictionary - official dictionary created by the team on the forum bezpieka.org.* 1

   statistically-likely-usernames - wordlists for creating statistically likely username lists.

##### :black_small_square: Bounty platforms


   YesWeHack - bug bounty platform with infosec jobs.

   Openbugbounty - allows any security researcher reporting a vulnerability on any website.

   hackerone - global hacker community to surface the most relevant security issues.

   bugcrowd - crowdsourced cybersecurity for the enterprise.

   Crowdshield - crowdsourced security & bug bounty management.

   Synack - crowdsourced security & bug bounty programs, crowd security intelligence platform, and more.

   Hacktrophy - bug bounty platform.

##### :black_small_square: Web Training Apps (local installation)


   OWASP-VWAD - comprehensive and well maintained registry of all known vulnerable web applications.

   DVWA - PHP/MySQL web application that is damn vulnerable.

   metasploitable2 - vulnerable web application amongst security researchers.

   metasploitable3 - is a VM that is built from the ground up with a large amount of security vulnerabilities.

   DSVW - is a deliberately vulnerable web application written in under 100 lines of code.

   OWASP Mutillidae II - free, open source, deliberately vulnerable web-application.

   OWASP Juice Shop Project - the most bug-free vulnerable application in existence.

   OWASP Node js Goat Project - OWASP Top 10 security risks apply to web apps developed using Node.js.

   juicy-ctf - run Capture the Flags and Security Trainings with OWASP Juice Shop.

   SecurityShepherd - web and mobile application security training platform.

   Security Ninjas - open source application security training program.

   hackazon - a modern vulnerable web app.

   dvna - damn vulnerable NodeJS application.

   django-DefectDojo - is an open-source application vulnerability correlation and security orchestration tool.

   Google Gruyere - web application exploits and defenses.

   Bodhi - is a playground focused on learning the exploitation of client-side web vulnerabilities.

   Websploit - single vm lab with the purpose of combining several vulnerable appliations in one environment.

   vulhub - pre-built Vulnerable Environments based on docker-compose.

   CloudGoat 2 - the new & improved "Vulnerable by Design"
AWS deployment tool.

   secDevLabs - is a laboratory for learning secure web development in a practical manner.

   CORS-vulnerable-Lab - sample vulnerable code and its exploit code.

   RootTheBox - a Game of Hackers (CTF Scoreboard & Game Manager).

   KONTRA - application security training (OWASP Top Web & Api).

##### :black_small_square: Labs (ethical hacking platforms/trainings/CTFs)


   Offensive Security - true performance-based penetration testing training for over a decade.

   Hack The Box - online platform allowing you to test your penetration testing skills.

   Hacking-Lab - online ethical hacking, computer network and security challenge platform.

   pwnable.kr - non-commercial wargame site which provides various pwn challenges.

   Pwnable.tw - is a wargame site for hackers to test and expand their binary exploiting skills.

   picoCTF - is a free computer security game targeted at middle and high school students.

   CTFlearn - is an online platform built to help ethical hackers learn and practice their cybersecurity knowledge.

   ctftime - CTF archive and a place, where you can get some another CTF-related info.

   Silesia Security Lab - high quality security testing services.

   Practical Pentest Labs - pentest lab, take your Hacking skills to the next level.

   Root Me - the fast, easy, and affordable way to train your hacking skills.

   rozwal.to - a great platform to train your pentesting skills.

   TryHackMe - learning Cyber Security made easy.

   hackxor - is a realistic web application hacking game, designed to help players of all abilities develop their skills.

   Hack Yourself First - it's full of nasty app sec holes.

   OverTheWire - can help you to learn and practice security concepts in the form of fun-filled games.

   Wizard Labs - is an online Penetration Testing Lab.

   PentesterLab - provides vulnerable systems that can be used to test and understand vulnerabilities.

   RingZer0 - tons of challenges designed to test and improve your hacking skills.

   try2hack - several security-oriented challenges for your entertainment.

   Ubeeri - preconfigured lab environments.

   Pentestit - emulate IT infrastructures of real companies for legal pen testing and improving pentest skills.

   Microcorruption - reversal challenges done in the web interface.

   Crackmes - download crackmes to help improve your reverse engineering skills.

   DomGoat - DOM XSS security learning and practicing platform.

   Stereotyped Challenges - upgrade your web hacking techniques today!

   Vulnhub - allows anyone to gain practical 'hands-on' experience in digital security.

   W3Challs - is a penetration testing training platform, which offers various computer challenges.

   RingZer0 CTF - offers you tons of challenges designed to test and improve your hacking skills.

   Hack.me - a platform where you can build, host and share vulnerable web apps for educational purposes.

   HackThis! - discover how hacks, dumps and defacements are performed and secure your website.

   Enigma Group WebApp Training - these challenges cover the exploits listed in the OWASP Top 10 Project.

   Reverse Engineering Challenges - challenges, exercises, problems and tasks - by level, by type, and more.

   0x00sec - the home of the Hacker - Malware, Reverse Engineering, and Computer Science.

   We Chall - there are exist a lots of different challenge types.

   Hacker Gateway - is the go-to place for hackers who want to test their skills.

   Hacker101 - is a free class for web security.

   contained.af - a stupid game for learning about containers, capabilities, and syscalls.

   flAWS challenge! - a series of levels you'll learn about common mistakes and gotchas when using AWS.

   CyberSec WTF - provides web hacking challenges derived from bounty write-ups.

   CTF Challenge - CTF Web App challenges.

   gCTF - most of the challenges used in the Google CTF 2017.

   Hack This Site - is a free, safe and legal training ground for hackers.

   Attack & Defense - is a browser-based cloud labs.

   Cryptohack - a fun platform for learning modern cryptography.

   Cryptopals - the cryptopals crypto challenges.

##### :black_small_square: CTF platforms


   fbctf - platform to host Capture the Flag competitions.

   ctfscoreboard - scoreboard for Capture The Flag competitions.

##### :black_small_square: Other resources


   Bugcrowd University - open source education content for the researcher community.

   OSCPRepo - a list of resources and scripts that I have been gathering in preparation for the OSCP.

   OWASP Top 10: Real-World Examples - test your web apps with real-world examples (two-part series).

   phrack.org - an awesome collection of articles from several respected hackers and other thinkers.

   Practical-Ethical-Hacking-Resources - compilation of resources from TCM's Udemy Course.

#### Your daily knowledge and news  [[TOC]](#anger-table-of-contents)

##### :black_small_square: RSS Readers


   Feedly - organize, read and share what matters to you.

   Inoreader - similar to feedly with a support for filtering what you fetch from rss.

##### :black_small_square: IRC Channels


   #hackerspaces - hackerspace IRC channels.

##### :black_small_square: Security


   The Hacker News - leading news source dedicated to promoting awareness for security experts and hackers.

   Latest Hacking News - provides the latest hacking news, exploits and vulnerabilities for ethical hackers.

   Security Newsletter - security news as a weekly digest (email notifications).

   Google Online Security Blog - the latest news and insights from Google on security and safety on the Internet.

   Qualys Blog - expert network security guidance and news.

   DARKReading - connecting the Information Security Community.

   Darknet - latest hacking tools, hacker news, cybersecurity best practices, ethical hacking & pen-testing.

   publiclyDisclosed - public disclosure watcher who keeps you up to date about the recently disclosed bugs.

   Reddit - Hacking - a subreddit dedicated to hacking and hackers.

   Packet Storm - information security services, news, files, tools, exploits, advisories and whitepapers.

   Sekurak - about security, penetration tests, vulnerabilities and many others (PL/EN).

   nf.sec - basic aspects and mechanisms of Linux operating system security (PL).

##### :black_small_square: Other/All-in-one


   Changelog - is a community of hackers; news & podcasts for developers and hackers.

#### Other Cheat Sheets  [[TOC]](#anger-table-of-contents)

###### Build your own DNS Servers


   Unbound DNS Tutorial - a validating, recursive, and caching DNS server.

   Knot Resolver on Fedora - how to get faster and more secure DNS resolution with Knot Resolver on Fedora.

   DNS-over-HTTPS - tutorial to setup your own DNS-over-HTTPS (DoH) server.

   dns-over-https - a cartoon intro to DNS over HTTPS.

   DNS-over-TLS - following to your DoH server, setup your DNS-over-TLS (DoT) server.

   DNS Servers - how (and why) i run my own DNS Servers.

###### Build your own Certificate Authority


   OpenSSL Certificate Authority - build your own certificate authority (CA) using the OpenSSL tools.

   step-ca Certificate Authority - build your own certificate authority (CA) using open source step-ca.

###### Build your own System/Virtual Machine


   os-tutorial - how to create an OS from scratch.

   Write your Own Virtual Machine - how to write your own virtual machine (VM).

   x86 Bare Metal Examples - dozens of minimal operating systems to learn x86 system programming.

   simple-computer - the scott CPU from "But How Do It Know?" by J. Clark Scott.

   littleosbook - the little book about OS development.

###### DNS Servers list (privacy)

| IP | URL |
| :--- | :--- |
| **`84.200.69.80`** | [dns.watch](https://dns.watch/) |
| **`94.247.43.254`** | [opennic.org](https://www.opennic.org/) |
| **`64.6.64.6`** | [verisign.com](https://www.verisign.com/en_US/security-services/public-dns/index.xhtml) |
| **`89.233.43.71`** | [censurfridns.dk](https://blog.uncensoreddns.org/) |
| **`1.1.1.1`** | [cloudflare.com](https://1.1.1.1/) |
| **`94.130.110.185`** | [dnsprivacy.at](https://dnsprivacy.at/) |

###### TOP Browser extensions

| Extension name | Description |
| :--- | :--- |
| **`IPvFoo`** | Display the server IP address and HTTPS information across all page elements. |
| **`FoxyProxy`** | Simplifies configuring browsers to access proxy-servers. |
| **`HTTPS Everywhere`** | Automatically use HTTPS security on many sites. |
| **`uMatrix`** | Point & click to forbid/allow any class of requests made by your browser. |
| **`uBlock Origin`** | An efficient blocker: easy on memory and CPU footprint. |
| **`Session Buddy`** | Manage browser tabs and bookmarks with ease. |
| **`SuperSorter`** | Sort bookmarks recursively, delete duplicates, merge folders, and more. |
| **`Clear Cache`** | Clear your cache and browsing data. |
| **`d3coder`** | Encoding/Decoding plugin for various types of encoding. |
| **`Web Developer`** | Adds a toolbar button with various web developer tools. |
| **`ThreatPinch Lookup`** | Add threat intelligence hover tool tips. |

###### TOP Burp extensions

| Extension name | Description |
| :--- | :--- |
| **`Active Scan++`** | Extends Burp's active and passive scanning capabilities. |
| **`Autorize`** | Automatically detects authorization enforcement. |
| **`AuthMatrix`** | A simple matrix grid to define the desired levels of access privilege. |
| **`Logger++`** | Logs requests and responses for all Burp tools in a sortable table. |
| **`Bypass WAF`** | Adds headers useful for bypassing some WAF devices. |
| **`JSON Beautifier`** | Beautifies JSON content in the HTTP message viewer. |
| **`JSON Web Tokens`** | Enables Burp to decode and manipulate JSON web tokens. |
| **`CSP Auditor`** | Displays CSP headers for responses, and passively reports CSP weaknesses. |
| **`CSP-Bypass`** | Passively scans for CSP headers that contain known bypasses. |
| **`Hackvertor`** | Converts data using a tag-based configuration to apply various encoding. |
| **`HTML5 Auditor`** | Scans for usage of risky HTML5 features. |
| **`Software Vulnerability Scanner`** | Vulnerability scanner based on vulners.com audit API. |
| **`Turbo Intruder`** | Is a powerful bruteforcing tool. |
| **`Upload Scanner`** | Upload a number of different file types, laced with different forms of payload. |

###### Hack Mozilla Firefox address bar

In Firefox's address bar, you can limit results by typing special characters before or after your term:

- `^` - for matches in your browsing history
- `*` - for matches in your bookmarks.
- `%` - for matches in your currently open tabs.
- `#` - for matches in page titles.
- `@` - for matches in web addresses.

###### Chrome hidden commands

- `chrome://chrome-urls` - list of all commands
- `chrome://flags` - enable experiments and development features
- `chrome://interstitials` - errors and warnings
- `chrome://net-internals` - network internals (events, dns, cache)
- `chrome://network-errors` - network errors
- `chrome://net-export` - start logging future network activity to a file
- `chrome://safe-browsing` - safe browsing options
- `chrome://user-actions` - record all user actions
- `chrome://restart` - restart chrome
- `chrome://dino` - ERR_INTERNET_DISCONNECTED...
- `cache:` - view the cached version of the web page

###### Bypass WAFs by Shortening IP Address (by [0xInfection](https://twitter.com/0xInfection))

IP addresses can be shortened by dropping the zeroes:

```
http://1.0.0.1 → http://1.1
http://127.0.0.1 → http://127.1
http://192.168.0.1 → http://192.168.1

http://0xC0A80001 or http://3232235521 → 192.168.0.1
http://192.168.257 → 192.168.1.1
http://192.168.516 → 192.168.2.4
```

> This bypasses WAF filters for SSRF, open-redirect, etc where any IP as input gets blacklisted.

For more information please see [How to Obscure Any URL](http://www.pc-help.org/obscure.htm) and [Magic IP Address Shortcuts](https://stuff-things.net/2014/09/25/magic-ip-address-shortcuts/).

###### Hashing, encryption and encoding (by [Michal Špaček](https://twitter.com/spazef0rze))

_Hashing_

plaintext :arrow_right: hash

hash :no_entry: plaintext

_Symmetric encryption_

plaintext :arrow_right: :key: :arrow_right: ciphertext

plaintext :arrow_left: :key: :arrow_left: ciphertext

(:key: shared key)

_Asymmetric encryption_

plaintext :arrow_right: :key: :arrow_right: ciphertext

plaintext :arrow_left: :part_alternation_mark: :arrow_left: ciphertext

(:key: public key, :part_alternation_mark: private key)

_Encoding_

text :arrow_right: encoded

text :arrow_left: encoded

#### Shell One-liners  [[TOC]](#anger-table-of-contents)

##### Table of Contents

* [terminal](#tool-terminal)
* [busybox](#tool-busybox)
* [mount](#tool-mount)
* [fuser](#tool-fuser)
* [lsof](#tool-lsof)
* [ps](#tool-ps)
* [top](#tool-top)
* [vmstat](#tool-vmstat)
* [iostat](#tool-iostat)
* [strace](#tool-strace)
* [kill](#tool-kill)
* [find](#tool-find)
* [diff](#tool-diff)
* [vimdiff](#tool-vimdiff)
* [tail](#tool-tail)
* [cpulimit](#tool-cpulimit)
* [pwdx](#tool-pwdx)
* [tr](#tool-tr)
* [chmod](#tool-chmod)
* [who](#tool-who)
* [last](#tool-last)
* [screen](#tool-screen)
* [script](#tool-script)
* [du](#tool-du)
* [inotifywait](#tool-inotifywait)
* [openssl](#tool-openssl)
* [secure-delete](#tool-secure-delete)
* [dd](#tool-dd)
* [gpg](#tool-gpg)
* [system-other](#tool-system-other)
* [curl](#tool-curl)
* [httpie](#tool-httpie)
* [ssh](#tool-ssh)
* [linux-dev](#tool-linux-dev)
* [tcpdump](#tool-tcpdump)
* [tcpick](#tool-tcpick)
* [ngrep](#tool-ngrep)
* [hping3](#tool-hping3)
* [nmap](#tool-nmap)
* [netcat](#tool-netcat)
* [socat](#tool-socat)
* [p0f](#tool-p0f)
* [gnutls-cli](#tool-gnutls-cli)
* [netstat](#tool-netstat)
* [rsync](#tool-rsync)
* [host](#tool-host)
* [dig](#tool-dig)
* [certbot](#tool-certbot)
* [network-other](#tool-network-other)
* [git](#tool-git)
* [awk](#tool-awk)
* [sed](#tool-sed)
* [grep](#tool-grep)
* [perl](#tool-perl)

##### Tool: [terminal](https://en.wikipedia.org/wiki/Linux_console)

###### Reload shell without exit

```bash
exec $SHELL -l
```

###### Close shell keeping all subprocess running

```bash
disown -a && exit
```

###### Exit without saving shell history

```bash
kill -9 $$
unset HISTFILE && exit
```

###### Perform a branching conditional

```bash
true && echo success
false || echo failed
```

###### Pipe stdout and stderr to separate commands

```bash
some_command > >(/bin/cmd_for_stdout) 2> >(/bin/cmd_for_stderr)
```

###### Redirect stdout and stderr each to separate files and print both to the screen

```bash
(some_command 2>&1 1>&3 | tee errorlog ) 3>&1 1>&2 | tee stdoutlog
```

###### List of commands you use most often

```bash
history | \
awk '{CMD[$2]++;count++;}END { for (a in CMD)print CMD[a] " " CMD[a]/count*100 "% " a;}' | \
grep -v "./" | \
column -c3 -s " " -t | \
sort -nr | nl | head -n 20
```

###### Sterilize bash history

```bash
function sterile() {

history | awk '$2 != "history" { $1=""; print $0 }' | egrep -vi "\
curl\b+.*(-E|--cert)\b+.*\b*|\
curl\b+.*--pass\b+.*\b*|\
curl\b+.*(-U|--proxy-user).*:.*\b*|\
curl\b+.*(-u|--user).*:.*\b*
.*(-H|--header).*(token|auth.*)\b+.*|\
wget\b+.*--.*password\b+.*\b*|\
http.?://.+:.+@.*\
" > $HOME/histbuff; history -r $HOME/histbuff;

}

export PROMPT_COMMAND="sterile"
```

> Look also: [A naive utility to censor credentials in command history](https://github.com/lbonanomi/go/blob/master/revisionist.go).

###### Quickly backup a file

```bash
cp filename{,.orig}
```

###### Empty a file (truncate to 0 size)

```bash
>filename
```

###### Delete all files in a folder that don't match a certain file extension

```bash
rm !(*.foo|*.bar|*.baz)
```

###### Pass multi-line string to a file

```bash
# cat >filename ... - overwrite the file
# cat >>filename ... - append to a file
cat > filename << __EOF__
data data data
__EOF__
```

###### Edit a file on a remote host using vim

```bash
vim scp://user@host//etc/fstab
```

###### Create a directory and change into it at the same time

```bash
mkd() { mkdir -p "$@" && cd "$@"; }
```

###### Convert uppercase files to lowercase files

```bash
rename 'y/A-Z/a-z/' *
```

###### Print a row of characters across the terminal

```bash
printf "%`tput cols`s" | tr ' ' '#'
```

###### Show shell history without line numbers

```bash
history | cut -c 8-
fc -l -n 1 | sed 's/^\s*//'
```

###### Run command(s) after exit session

```bash
cat > /etc/profile << __EOF__
_after_logout() {

username=$(whoami)

for _pid in $(ps afx | grep sshd | grep "$username" | awk '{print $1}') ; do

kill -9 $_pid

done

}
trap _after_logout EXIT
__EOF__
```

###### Generate a sequence of numbers

```bash
for ((i=1; i<=10; i+=2)) ; do echo $i ; done
# alternative: seq 1 2 10

for ((i=5; i<=10; ++i)) ; do printf '%02d\n' $i ; done
# alternative: seq -w 5 10

for i in {1..10} ; do echo $i ; done
```

###### Simple Bash filewatching

```bash
unset MAIL; export MAILCHECK=1; export MAILPATH='$FILE_TO_WATCH?$MESSAGE'
```

---

##### Tool: [busybox](https://www.busybox.net/)

###### Static HTTP web server

```bash
busybox httpd -p $PORT -h $HOME [-c httpd.conf]
```

___

##### Tool: [mount](https://en.wikipedia.org/wiki/Mount_(Unix))

###### Mount a temporary ram partition

```bash
mount -t tmpfs tmpfs /mnt -o size=64M
```

* `-t` - filesystem type
* `-o` - mount options

###### Remount a filesystem as read/write

```bash
mount -o remount,rw /
```

___

##### Tool: [fuser](https://en.wikipedia.org/wiki/Fuser_(Unix))

###### Show which processes use the files/directories

```bash
fuser /var/log/daemon.log
fuser -v /home/supervisor
```

###### Kills a process that is locking a file

```bash
fuser -ki filename
```

* `-i` - interactive option

###### Kills a process that is locking a file with specific signal

```bash
fuser -k -HUP filename
```

* `--list-signals` - list available signal names

###### Show what PID is listening on specific port

```bash
fuser -v 53/udp
```

###### Show all processes using the named filesystems or block device

```bash
fuser -mv /var/www
```

___

##### Tool: [lsof](https://en.wikipedia.org/wiki/Lsof)

###### Show process that use internet connection at the moment

```bash
lsof -P -i -n
```

###### Show process that use specific port number

```bash
lsof -i tcp:443
```

###### Lists all listening ports together with the PID of the associated process

```bash
lsof -Pan -i tcp -i udp
```

###### List all open ports and their owning executables

```bash
lsof -i -P | grep -i "listen"
```

###### Show all open ports

```bash
lsof -Pnl -i
```

###### Show open ports (LISTEN)

```bash
lsof -Pni4 | grep LISTEN | column -t
```

###### List all files opened by a particular command

```bash
lsof -c "process"
```

###### View user activity per directory

```bash
lsof -u username -a +D /etc
```

###### Show 10 largest open files

```bash
lsof / | \
awk '{ if($7 > 1048576) print $7/1048576 "MB" " " $9 " " $1 }' | \
sort -n -u | tail | column -t
```

###### Show current working directory of a process

```bash
lsof -p | grep cwd
```

___

##### Tool: [ps](https://en.wikipedia.org/wiki/Ps_(Unix))

###### Show a 4-way scrollable process tree with full details

```bash
ps awwfux | less -S
```

###### Processes per user counter

```bash
ps hax -o user | sort | uniq -c | sort -r
```

###### Show all processes by name with main header

```bash
ps -lfC nginx
```

___

##### Tool: [find](https://en.wikipedia.org/wiki/Find_(Unix))

###### Find files that have been modified on your system in the past 60 minutes

```bash
find / -mmin 60 -type f
```

###### Find all files larger than 20M

```bash
find / -type f -size +20M
```

###### Find duplicate files (based on MD5 hash)

```bash
find -type f -exec md5sum '{}' ';' | sort | uniq --all-repeated=separate -w 33
```

###### Change permission only for files

```bash
cd /var/www/site && find . -type f -exec chmod 766 {} \;
cd /var/www/site && find . -type f -exec chmod 664 {} +
```

###### Change permission only for directories

```bash
cd /var/www/site && find . -type d -exec chmod g+x {} \;
cd /var/www/site && find . -type d -exec chmod g+rwx {} +
```

###### Find files and directories for specific user/group

```bash
# User:
find . -user -print
find /etc -type f -user -name "*.conf"

# Group:
find /opt -group
find /etc -type f -group -iname "*.conf"
```

###### Find files and directories for all without specific user/group

```bash
# User:
find . \! -user -print

# Group:
find . \! -group
```

###### Looking for files/directories that only have certain permission

```bash
# User
find . -user -perm -u+rw # -rw-r--r--
find /home -user $(whoami) -perm 777 # -rwxrwxrwx

# Group:
find /home -type d -group -perm 755 # -rwxr-xr-x
```

###### Delete older files than 60 days

```bash
find . -type f -mtime +60 -delete
```

###### Recursively remove all empty sub-directories from a directory

```bash
find . -depth -type d -empty -exec rmdir {} \;
```

###### How to find all hard links to a file

```bash
find -xdev -samefile filename
```

###### Recursively find the latest modified files

```bash
find . -type f -exec stat --format '%Y :%y %n' "{}" \; | sort -nr | cut -d: -f2- | head
```

###### Recursively find/replace of a string with sed

```bash
find . -not -path '*/\.git*' -type f -print0 | xargs -0 sed -i 's/foo/bar/g'
```

###### Recursively find/replace of a string in directories and file names

```bash
find . -depth -name '*test*' -execdir bash -c 'mv -v "$1" "${1//foo/bar}"' _ {} \;
```

###### Recursively find suid executables

```bash
find / \( -perm -4000 -o -perm -2000 \) -type f -exec ls -la {} \;
```

___

##### Tool: [top](https://en.wikipedia.org/wiki/Top_(software))

###### Use top to monitor only all processes with the specific string

```bash
top -p $(pgrep -d , )
```

* `` - process containing string (eg. nginx, worker)

___

##### Tool: [vmstat](https://en.wikipedia.org/wiki/Vmstat)

###### Show current system utilization (fields in kilobytes)

```bash
vmstat 2 20 -t -w
```

* `2` - number of times with a defined time interval (delay)
* `20` - each execution of the command (count)
* `-t` - show timestamp
* `-w` - wide output
* `-S M` - output of the fields in megabytes instead of kilobytes

###### Show current system utilization will get refreshed every 5 seconds

```bash
vmstat 5 -w
```

###### Display report a summary of disk operations

```bash
vmstat -D
```

###### Display report of event counters and memory stats

```bash
vmstat -s
```

###### Display report about kernel objects stored in slab layer cache

```bash
vmstat -m
```

##### Tool: [iostat](https://en.wikipedia.org/wiki/Iostat)

###### Show information about the CPU usage, and I/O statistics about all the partitions

```bash
iostat 2 10 -t -m
```

* `2` - number of times with a defined time interval (delay)
* `10` - each execution of the command (count)
* `-t` - show timestamp
* `-m` - fields in megabytes (`-k` - in kilobytes, default)

###### Show information only about the CPU utilization

```bash
iostat 2 10 -t -m -c
```

###### Show information only about the disk utilization

```bash
iostat 2 10 -t -m -d
```

###### Show information only about the LVM utilization

```bash
iostat -N
```

___

##### Tool: [strace](https://en.wikipedia.org/wiki/Strace)

###### Track with child processes

```bash
# 1)
strace -f -p $(pidof glusterfsd)

# 2)
strace -f $(pidof php-fpm | sed 's/\([0-9]*\)/\-p \1/g')
```

###### Track process with 30 seconds limit

```bash
timeout 30 strace $(< /var/run/zabbix/zabbix_agentd.pid)
```

###### Track processes and redirect output to a file

```bash
ps auxw | grep '[a]pache' | awk '{print " -p " $2}' | \
xargs strace -o /tmp/strace-apache-proc.out
```

###### Track with print time spent in each syscall and limit length of print strings

```bash
ps auxw | grep '[i]init_policy' | awk '{print " -p " $2}' | \
xargs strace -f -e trace=network -T -s 10000
```

###### Track the open request of a network port

```bash
strace -f -e trace=bind nc -l 80
```

###### Track the open request of a network port (show TCP/UDP)

```bash
strace -f -e trace=network nc -lu 80
```

___

##### Tool: [kill](https://en.wikipedia.org/wiki/Kill_(command))

###### Kill a process running on port

```bash
kill -9 $(lsof -i : | awk '{l=$2} END {print l}')
```

___

##### Tool: [diff](https://en.wikipedia.org/wiki/Diff)

###### Compare two directory trees

```bash
diff <(cd directory1 && find | sort) <(cd directory2 && find | sort)
```

###### Compare output of two commands

```bash
diff <(cat /etc/passwd) <(cut -f2 /etc/passwd)
```

___

##### Tool: [vimdiff](http://vimdoc.sourceforge.net/htmldoc/diff.html)

###### Highlight the exact differences, based on characters and words

```bash
vimdiff file1 file2
```

###### Compare two JSON files

```bash
vimdiff <(jq -S . A.json) <(jq -S . B.json)
```

###### Compare Hex dump

```bash
d(){ vimdiff <(f $1) <(f $2);};f(){ hexdump -C $1 | cut -d' ' -f3- | tr -s ' ';}; d ~/bin1 ~/bin2
```

###### diffchar

Save [diffchar](https://raw.githubusercontent.com/vim-scripts/diffchar.vim/master/plugin/diffchar.vim) @ `~/.vim/plugins`

Click `F7` to switch between diff modes

Usefull `vimdiff` commands:

* `qa` to exit all windows
* `:vertical resize 70` to resize window
* set window width `Ctrl+W [N columns]+(Shift+)<\>`

___

##### Tool: [tail](https://en.wikipedia.org/wiki/Tail_(Unix))

###### Annotate tail -f with timestamps

```bash
tail -f file | while read ; do echo "$(date +%T.%N) $REPLY" ; done
```

###### Analyse an Apache access log for the most common IP addresses

```bash
tail -10000 access_log | awk '{print $1}' | sort | uniq -c | sort -n | tail
```

###### Analyse web server log and show only 5xx http codes

```bash
tail -n 100 -f /path/to/logfile | grep "HTTP/[1-2].[0-1]\" [5]"
```

___

##### Tool: [tar](https://en.wikipedia.org/wiki/Tar_(computing))

###### System backup with exclude specific directories

```bash
cd /
tar -czvpf /mnt/system$(date +%d%m%Y%s).tgz --directory=/ \
--exclude=proc/* --exclude=sys/* --exclude=dev/* --exclude=mnt/* .
```

###### System backup with exclude specific directories (pigz)

```bash
cd /
tar cvpf /backup/snapshot-$(date +%d%m%Y%s).tgz --directory=/ \
--exclude=proc/* --exclude=sys/* --exclude=dev/* \
--exclude=mnt/* --exclude=tmp/* --use-compress-program=pigz .
```

___

##### Tool: [dump](https://en.wikipedia.org/wiki/Dump_(program))

###### System backup to file

```bash
dump -y -u -f /backup/system$(date +%d%m%Y%s).lzo /
```

###### Restore system from lzo file

```bash
cd /
restore -rf /backup/system$(date +%d%m%Y%s).lzo
```

___

##### Tool: [cpulimit](http://cpulimit.sourceforge.net/)

###### Limit the cpu usage of a process

```bash
cpulimit -p pid -l 50
```

___

##### Tool: [pwdx](https://www.cyberciti.biz/faq/unix-linux-pwdx-command-examples-usage-syntax/)

###### Show current working directory of a process

```bash
pwdx
```

___

##### Tool: [taskset](https://www.cyberciti.biz/faq/taskset-cpu-affinity-command/)

###### Start a command on only one CPU core

```bash
taskset -c 0
```

___

##### Tool: [tr](https://en.wikipedia.org/wiki/Tr_(Unix))

###### Show directories in the PATH, one per line

```bash
tr : '\n' <<<$PATH
```

___

##### Tool: [chmod](https://en.wikipedia.org/wiki/Chmod)

###### Remove executable bit from all files in the current directory

```bash
chmod -R -x+X *
```

###### Restore permission for /bin/chmod

```bash
# 1:
cp /bin/ls chmod.01
cp /bin/chmod chmod.01
./chmod.01 700 file

# 2:
/bin/busybox chmod 0700 /bin/chmod

# 3:
setfacl --set u::rwx,g::---,o::--- /bin/chmod
```

___

##### Tool: [who](https://en.wikipedia.org/wiki/Who_(Unix))

###### Find last reboot time

```bash
who -b
```

###### Detect a user sudo-su'd into the current shell

```bash
[[ $(who -m | awk '{ print $1 }') == $(whoami) ]] || echo "You are su-ed to $(whoami)"
```

___

##### Tool: [last](https://www.howtoforge.com/linux-last-command/)

###### Was the last reboot a panic?

```bash
(last -x -f $(ls -1t /var/log/wtmp* | head -2 | tail -1); last -x -f /var/log/wtmp) | \
grep -A1 reboot | head -2 | grep -q shutdown && echo "Expected reboot" || echo "Panic reboot"
```

___

##### Tool: [screen](https://en.wikipedia.org/wiki/GNU_Screen)

###### Start screen in detached mode

```bash
screen -d -m
```

###### Attach to an existing screen session

```bash
screen -r -d
```

___

##### Tool: [script](https://en.wikipedia.org/wiki/Script_(Unix))

###### Record and replay terminal session

```bash
### Record session
# 1)
script -t 2>~/session.time -a ~/session.log

# 2)
script --timing=session.time session.log

### Replay session
scriptreplay --timing=session.time session.log
```

___

##### Tool: [du](https://en.wikipedia.org/wiki/GNU_Screen)

###### Show 20 biggest directories with 'K M G'

```bash
du | \
sort -r -n | \
awk '{split("K M G",v); s=1; while($1>1024){$1/=1024; s++} print int($1)" "v[s]"\t"$2}' | \
head -n 20
```

___

##### Tool: [inotifywait](https://en.wikipedia.org/wiki/GNU_Screen)

###### Init tool everytime a file in a directory is modified

```bash
while true ; do inotifywait -r -e MODIFY dir/ && ls dir/ ; done;
```

___

##### Tool: [openssl](https://www.openssl.org/)

###### Testing connection to the remote host

```bash
echo | openssl s_client -connect google.com:443 -showcerts
```

###### Testing connection to the remote host (debug mode)

```bash
echo | openssl s_client -connect google.com:443 -showcerts -tlsextdebug -status
```

###### Testing connection to the remote host (with SNI support)

```bash
echo | openssl s_client -showcerts -servername google.com -connect google.com:443
```

###### Testing connection to the remote host with specific ssl version

```bash
openssl s_client -tls1_2 -connect google.com:443
```

###### Testing connection to the remote host with specific ssl cipher

```bash
openssl s_client -cipher 'AES128-SHA' -connect google.com:443
```

###### Verify 0-RTT

```bash
_host="example.com"

cat > req.in << __EOF__
HEAD / HTTP/1.1
Host: $_host
Connection: close
__EOF__

openssl s_client -connect ${_host}:443 -tls1_3 -sess_out session.pem -ign_eof < req.in
openssl s_client -connect ${_host}:443 -tls1_3 -sess_in session.pem -early_data req.in
```

###### Generate private key without passphrase

```bash
# _len: 2048, 4096
( _fd="private.key" ; _len="2048" ; \
openssl genrsa -out ${_fd} ${_len} )
```

###### Generate private key with passphrase

```bash
# _ciph: aes128, aes256
# _len: 2048, 4096
( _ciph="aes128" ; _fd="private.key" ; _len="2048" ; \
openssl genrsa -${_ciph} -out ${_fd} ${_len} )
```

###### Remove passphrase from private key

```bash
( _fd="private.key" ; _fd_unp="private_unp.key" ; \
openssl rsa -in ${_fd} -out ${_fd_unp} )
```

###### Encrypt existing private key with a passphrase

```bash
# _ciph: aes128, aes256
( _ciph="aes128" ; _fd="private.key" ; _fd_pass="private_pass.key" ; \
openssl rsa -${_ciph} -in ${_fd} -out ${_fd_pass}
```

###### Check private key

```bash
( _fd="private.key" ; \
openssl rsa -check -in ${_fd} )
```

###### Get public key from private key

```bash
( _fd="private.key" ; _fd_pub="public.key" ; \
openssl rsa -pubout -in ${_fd} -out ${_fd_pub} )
```

###### Generate private key and CSR

```bash
( _fd="private.key" ; _fd_csr="request.csr" ; _len="2048" ; \
openssl req -out ${_fd_csr} -new -newkey rsa:${_len} -nodes -keyout ${_fd} )
```

###### Generate CSR

```bash
( _fd="private.key" ; _fd_csr="request.csr" ; \
openssl req -out ${_fd_csr} -new -key ${_fd} )
```

###### Generate CSR (metadata from existing certificate)

> Where `private.key` is the existing private key. As you can see you do not generate this CSR from your certificate (public key). Also you do not generate the "same" CSR, just a new one to request a new certificate.

```bash
( _fd="private.key" ; _fd_csr="request.csr" ; _fd_crt="cert.crt" ; \
openssl x509 -x509toreq -in ${_fd_crt} -out ${_fd_csr} -signkey ${_fd} )
```

###### Generate CSR with -config param

```bash
( _fd="private.key" ; _fd_csr="request.csr" ; \
openssl req -new -sha256 -key ${_fd} -out ${_fd_csr} \
-config <(
cat << __EOF__
[req]
default_bits = 2048
default_md = sha256
prompt = no
distinguished_name = dn
req_extensions = req_ext

[ dn ]
C = ""
ST = ""
L = ""
O = ""
OU = ""
CN = ""

[ req_ext ]
subjectAltName = @alt_names

[ alt_names ]
DNS.1 =
DNS.2 =
DNS.3 =
__EOF__
))
```

Other values in `[ dn ]`:

```
countryName = "DE" # C=
stateOrProvinceName = "Hessen" # ST=
localityName = "Keller" # L=
postalCode = "424242" # L/postalcode=
postalAddress = "Keller" # L/postaladdress=
streetAddress = "Crater 1621" # L/street=
organizationName = "apfelboymschule" # O=
organizationalUnitName = "IT Department" # OU=
commonName = "example.com" # CN=
emailAddress = "[email protected]" # CN/emailAddress=
```

Example of `oids` (you'll probably also have to make OpenSSL know about the new fields required for EV by adding the following under `[new_oids]`):

```
[req]
...
oid_section = new_oids

[ new_oids ]
postalCode = 2.5.4.17
streetAddress = 2.5.4.9
```

Full example:

```bash
( _fd="private.key" ; _fd_csr="request.csr" ; \
openssl req -new -sha256 -key ${_fd} -out ${_fd_csr} \
-config <(
cat << __EOF__
[req]
default_bits = 2048
default_md = sha256
prompt = no
distinguished_name = dn
req_extensions = req_ext
oid_section = new_oids

[ new_oids ]
serialNumber = 2.5.4.5
streetAddress = 2.5.4.9
postalCode = 2.5.4.17
businessCategory = 2.5.4.15

[ dn ]
serialNumber=00001111
businessCategory=Private Organization
jurisdictionC=DE
C=DE
ST=Hessen
L=Keller
postalCode=424242
streetAddress=Crater 1621
O=AV Company
OU=IT
CN=example.com

[ req_ext ]
subjectAltName = @alt_names

[ alt_names ]
DNS.1 = example.com
__EOF__
))
```

For more information please look at these great explanations:

- [RFC 5280](https://tools.ietf.org/html/rfc5280)
- [How to create multidomain certificates using config files](https://apfelboymchen.net/gnu/notes/openssl%20multidomain%20with%20config%20files.html)
- [Generate a multi domains certificate using config files](https://gist.github.com/romainnorberg/464758a6620228b977212a3cf20c3e08)
- [Your OpenSSL CSR command is out of date](https://expeditedsecurity.com/blog/openssl-csr-command/)
- [OpenSSL example configuration file](https://www.tbs-certificats.com/openssl-dem-server-cert.cnf)
- [Object Identifiers (OIDs)](https://www.alvestrand.no/objectid/)
- [openssl objects.txt](https://github.com/openssl/openssl/blob/master/crypto/objects/objects.txt)

###### List available EC curves

```bash
openssl ecparam -list_curves
```

###### Print ECDSA private and public keys

```bash
( _fd="private.key" ; \
openssl ec -in ${_fd} -noout -text )

# For x25519 only extracting public key
( _fd="private.key" ; _fd_pub="public.key" ; \
openssl pkey -in ${_fd} -pubout -out ${_fd_pub} )
```

###### Generate ECDSA private key

```bash
# _curve: prime256v1, secp521r1, secp384r1
( _fd="private.key" ; _curve="prime256v1" ; \
openssl ecparam -out ${_fd} -name ${_curve} -genkey )

# _curve: X25519
( _fd="private.key" ; _curve="x25519" ; \
openssl genpkey -algorithm ${_curve} -out ${_fd} )
```

###### Generate private key and CSR (ECC)

```bash
# _curve: prime256v1, secp521r1, secp384r1
( _fd="domain.com.key" ; _fd_csr="domain.com.csr" ; _curve="prime256v1" ; \
openssl ecparam -out ${_fd} -name ${_curve} -genkey ; \
openssl req -new -key ${_fd} -out ${_fd_csr} -sha256 )
```

###### Generate self-signed certificate

```bash
# _len: 2048, 4096
( _fd="domain.key" ; _fd_out="domain.crt" ; _len="2048" ; _days="365" ; \
openssl req -newkey rsa:${_len} -nodes \
-keyout ${_fd} -x509 -days ${_days} -out ${_fd_out} )
```

###### Generate self-signed certificate from existing private key

```bash
# _len: 2048, 4096
( _fd="domain.key" ; _fd_out="domain.crt" ; _days="365" ; \
openssl req -key ${_fd} -nodes \
-x509 -days ${_days} -out ${_fd_out} )
```

###### Generate self-signed certificate from existing private key and csr

```bash
# _len: 2048, 4096
( _fd="domain.key" ; _fd_csr="domain.csr" ; _fd_out="domain.crt" ; _days="365" ; \
openssl x509 -signkey ${_fd} -nodes \
-in ${_fd_csr} -req -days ${_days} -out ${_fd_out} )
```

###### Generate DH public parameters

```bash
( _dh_size="2048" ; \
openssl dhparam -out /etc/nginx/ssl/dhparam_${_dh_size}.pem "$_dh_size" )
```

###### Display DH public parameters

```bash
openssl pkeyparam -in dhparam.pem -text
```

###### Extract private key from pfx

```bash
( _fd_pfx="cert.pfx" ; _fd_key="key.pem" ; \
openssl pkcs12 -in ${_fd_pfx} -nocerts -nodes -out ${_fd_key} )
```

###### Extract private key and certs from pfx

```bash
( _fd_pfx="cert.pfx" ; _fd_pem="key_certs.pem" ; \
openssl pkcs12 -in ${_fd_pfx} -nodes -out ${_fd_pem} )
```

###### Extract certs from p7b

```bash
# PKCS#7 file doesn't include private keys.
( _fd_p7b="cert.p7b" ; _fd_pem="cert.pem" ; \
openssl pkcs7 -inform DER -outform PEM -in ${_fd_p7b} -print_certs > ${_fd_pem})
# or:
openssl pkcs7 -print_certs -in -in ${_fd_p7b} -out ${_fd_pem})
```

###### Convert DER to PEM

```bash
( _fd_der="cert.crt" ; _fd_pem="cert.pem" ; \
openssl x509 -in ${_fd_der} -inform der -outform pem -out ${_fd_pem} )
```

###### Convert PEM to DER

```bash
( _fd_der="cert.crt" ; _fd_pem="cert.pem" ; \
openssl x509 -in ${_fd_pem} -outform der -out ${_fd_der} )
```

###### Verification of the private key

```bash
( _fd="private.key" ; \
openssl rsa -noout -text -in ${_fd} )
```

###### Verification of the public key

```bash
# 1)
( _fd="public.key" ; \
openssl pkey -noout -text -pubin -in ${_fd} )

# 2)
( _fd="private.key" ; \
openssl rsa -inform PEM -noout -in ${_fd} &> /dev/null ; \
if [ $? = 0 ] ; then echo -en "OK\n" ; fi )
```

###### Verification of the certificate

```bash
( _fd="certificate.crt" ; # format: pem, cer, crt \
openssl x509 -noout -text -in ${_fd} )
```

###### Verification of the CSR

```bash
( _fd_csr="request.csr" ; \
openssl req -text -noout -in ${_fd_csr} )
```

###### Check the private key and the certificate are match

```bash
(openssl rsa -noout -modulus -in private.key | openssl md5 ; \
openssl x509 -noout -modulus -in certificate.crt | openssl md5) | uniq
```

###### Check the private key and the CSR are match

```bash
(openssl rsa -noout -modulus -in private.key | openssl md5 ; \
openssl req -noout -modulus -in request.csr | openssl md5) | uniq
```

___

##### Tool: [secure-delete](https://wiki.archlinux.org/index.php/Securely_wipe_disk)

###### Secure delete with shred

```bash
shred -vfuz -n 10 file
shred --verbose --random-source=/dev/urandom -n 1 /dev/sda
```

###### Secure delete with scrub

```bash
scrub -p dod /dev/sda
scrub -p dod -r file
```

###### Secure delete with badblocks

```bash
badblocks -s -w -t random -v /dev/sda
badblocks -c 10240 -s -w -t random -v /dev/sda
```

###### Secure delete with secure-delete

```bash
srm -vz /tmp/file
sfill -vz /local
sdmem -v
swapoff /dev/sda5 && sswap -vz /dev/sda5
```

___

##### Tool: [dd](https://en.wikipedia.org/wiki/Dd_(Unix))

###### Show dd status every so often

```bash
dd status=progress
watch --interval 5 killall -USR1 dd
```

###### Redirect output to a file with dd

```bash
echo "string" | dd of=filename
```

___

##### Tool: [gpg](https://www.gnupg.org/)

###### Export public key

```bash
gpg --export --armor "" > username.pkey
```

* `--export` - export all keys from all keyrings or specific key
* `-a|--armor` - create ASCII armored output

###### Encrypt file

```bash
gpg -e -r "" dump.sql
```

* `-e|--encrypt` - encrypt data
* `-r|--recipient` - encrypt for specific

###### Decrypt file

```bash
gpg -o dump.sql -d dump.sql.gpg
```

* `-o|--output` - use as output file
* `-d|--decrypt` - decrypt data (default)

###### Search recipient

```bash
gpg --keyserver hkp://keyserver.ubuntu.com --search-keys ""
```

* `--keyserver` - set specific key server
* `--search-keys` - search for keys on a key server

###### List all of the packets in an encrypted file

```bash
gpg --batch --list-packets archive.gpg
gpg2 --batch --list-packets archive.gpg
```

___

##### Tool: [system-other](https://github.com/trimstray/the-book-of-secret-knowledge#tool-system-other)

###### Reboot system from init

```bash
exec /sbin/init 6
```

###### Init system from single user mode

```bash
exec /sbin/init
```

###### Show current working directory of a process

```bash
readlink -f /proc//cwd
```

###### Show actual pathname of the executed command

```bash
readlink -f /proc//exe
```

##### Tool: [curl](https://curl.haxx.se)

```bash
curl -Iks https://www.google.com
```

* `-I` - show response headers only
* `-k` - insecure connection when using ssl
* `-s` - silent mode (not display body)

```bash
curl -Iks --location -X GET -A "x-agent" https://www.google.com
```

* `--location` - follow redirects
* `-X` - set method
* `-A` - set user-agent

```bash
curl -Iks --location -X GET -A "x-agent" --proxy http://127.0.0.1:16379 https://www.google.com
```

* `--proxy [socks5://|http://]` - set proxy server

```bash
curl -o file.pdf -C - https://example.com/Aiju2goo0Ja2.pdf
```

* `-o` - write output to file
* `-C` - resume the transfer

###### Find your external IP address (external services)

```bash
curl ipinfo.io
curl ipinfo.io/ip
curl icanhazip.com
curl ifconfig.me/ip ; echo
```

###### Repeat URL request

```bash
# URL sequence substitution with a dummy query string:
curl -ks https://example.com/?[1-20]

# With shell 'for' loop:
for i in {1..20} ; do curl -ks https://example.com/ ; done
```

###### Check DNS and HTTP trace with headers for specific domains

```bash
### Set domains and external dns servers.
_domain_list=(google.com) ; _dns_list=("8.8.8.8" "1.1.1.1")

for _domain in "${_domain_list[@]}" ; do

printf '=%.0s' {1..48}

echo

printf "[\\e[1;32m+\\e[m] resolve: %s\\n" "$_domain"

for _dns in "${_dns_list[@]}" ; do

# Resolve domain.
host "${_domain}" "${_dns}"

echo

done

for _proto in http https ; do

printf "[\\e[1;32m+\\e[m] trace + headers: %s://%s\\n" "$_proto" "$_domain"

# Get trace and http headers.
curl -Iks -A "x-agent" --location "${_proto}://${_domain}"

echo

done

done

unset _domain_list _dns_list
```

___

##### Tool: [httpie](https://httpie.org/)

```bash
http -p Hh https://www.google.com
```

* `-p` - print request and response headers
* `H` - request headers
* `B` - request body
* `h` - response headers
* `b` - response body

```bash
http -p Hh https://www.google.com --follow --verify no
```

* `-F, --follow` - follow redirects
* `--verify no` - skip SSL verification

```bash
http -p Hh https://www.google.com --follow --verify no \
--proxy http:http://127.0.0.1:16379
```

* `--proxy [http:]` - set proxy server

##### Tool: [ssh](https://www.openssh.com/)

###### Escape Sequence

```
# Supported escape sequences:
~. - terminate connection (and any multiplexed sessions)
~B - send a BREAK to the remote system
~C - open a command line
~R - Request rekey (SSH protocol 2 only)
~^Z - suspend ssh
~# - list forwarded connections
~& - background ssh (when waiting for connections to terminate)
~? - this message
~~ - send the escape character by typing it twice
```

###### Compare a remote file with a local file

```bash
ssh user@host cat /path/to/remotefile | diff /path/to/localfile -
```

###### SSH connection through host in the middle

```bash
ssh -t reachable_host ssh unreachable_host
```

###### Run command over SSH on remote host

```bash
cat > cmd.txt << __EOF__
cat /etc/hosts
__EOF__

ssh host -l user $(&1 | tee -a "${_sesdir}/$(date +%Y%m%d).log"

}

# Alias:
alias ssh='_ssh_sesslog'
```

###### Using Keychain for SSH logins

```bash
### Delete all of ssh-agent's keys.
function _scl() {

/usr/bin/keychain --clear

}

### Add key to keychain.
function _scg() {

/usr/bin/keychain /path/to/private-key
source "$HOME/.keychain/$HOSTNAME-sh"

}
```

###### SSH login without processing any login scripts

```bash
ssh -tt user@host bash
```

###### SSH local port forwarding

Example 1:

```bash
# Forwarding our local 2250 port to nmap.org:443 from localhost through localhost
host1> ssh -L 2250:nmap.org:443 localhost

# Connect to the service:
host1> curl -Iks --location -X GET https://localhost:2250
```

Example 2:

```bash
# Forwarding our local 9051 port to db.d.x:5432 from localhost through node.d.y
host1> ssh -nNT -L 9051:db.d.x:5432 node.d.y

# Connect to the service:
host1> psql -U db_user -d db_dev -p 9051 -h localhost
```

* `-n` - redirects stdin from `/dev/null`
* `-N` - do not execute a remote command
* `-T` - disable pseudo-terminal allocation

###### SSH remote port forwarding

```bash
# Forwarding our local 9051 port to db.d.x:5432 from host2 through node.d.y
host1> ssh -nNT -R 9051:db.d.x:5432 node.d.y

# Connect to the service:
host2> psql -U postgres -d postgres -p 8000 -h localhost
```

___

##### Tool: [linux-dev](https://www.tldp.org/LDP/abs/html/devref1.html)

###### Testing remote connection to port

```bash
timeout 1 bash -c "//" >/dev/null 2>&1 ; echo $?
```

* `` - set remote host
* `` - set destination port

###### Read and write to TCP or UDP sockets with common bash tools

```bash
exec 5<>/dev/tcp//; cat <&5 & cat >&5; exec 5>&-
```

___

##### Tool: [tcpdump](http://www.tcpdump.org/)

###### Filter incoming (on interface) traffic (specific )

```bash
tcpdump -ne -i eth0 -Q in host 192.168.252.1 and port 443
```

* `-n` - don't convert addresses (`-nn` will not resolve hostnames or ports)
* `-e` - print the link-level headers
* `-i [iface|any]` - set interface
* `-Q|-D [in|out|inout]` - choose send/receive direction (`-D` - for old tcpdump versions)
* `host [ip|hostname]` - set host, also `[host not]`
* `[and|or]` - set logic
* `port [1-65535]` - set port number, also `[port not]`

###### Filter incoming (on interface) traffic (specific ) and write to a file

```bash
tcpdump -ne -i eth0 -Q in host 192.168.252.1 and port 443 -c 5 -w tcpdump.pcap
```

* `-c [num]` - capture only num number of packets
* `-w [filename]` - write packets to file, `-r [filename]` - reading from file

###### Capture all ICMP packets

```bash
tcpdump -nei eth0 icmp
```

###### Check protocol used (TCP or UDP) for service

```bash
tcpdump -nei eth0 tcp port 22 -vv -X | egrep "TCP|UDP"
```

###### Display ASCII text (to parse the output using grep or other)

```bash
tcpdump -i eth0 -A -s0 port 443
```

###### Grab everything between two keywords

```bash
tcpdump -i eth0 port 80 -X | sed -n -e '/username/,/=ldap/ p'
```

###### Grab user and pass ever plain http

```bash
tcpdump -i eth0 port http -l -A | egrep -i \
'pass=|pwd=|log=|login=|user=|username=|pw=|passw=|passwd=|password=|pass:|user:|username:|password:|login:|pass |user ' \
--color=auto --line-buffered -B20
```

###### Extract HTTP User Agent from HTTP request header

```bash
tcpdump -ei eth0 -nn -A -s1500 -l | grep "User-Agent:"
```

###### Capture only HTTP GET and POST packets

```bash
tcpdump -ei eth0 -s 0 -A -vv \
'tcp[((tcp[12:1] & 0xf0) >> 2):4] = 0x47455420' or 'tcp[((tcp[12:1] & 0xf0) >> 2):4] = 0x504f5354'
```

or simply:

```bash
tcpdump -ei eth0 -s 0 -v -n -l | egrep -i "POST /|GET /|Host:"
```

###### Rotate capture files

```bash
tcpdump -ei eth0 -w /tmp/capture-%H.pcap -G 3600 -C 200
```

* `-G ` - pcap will be created every `` seconds
* `-C ` - close the current pcap and open a new one if is larger than ``

###### Top hosts by packets

```bash
tcpdump -ei enp0s25 -nnn -t -c 200 | cut -f 1,2,3,4 -d '.' | sort | uniq -c | sort -nr | head -n 20
```

###### Excludes any RFC 1918 private address

```bash
tcpdump -nei eth0 'not (src net (10 or 172.16/12 or 192.168/16) and dst net (10 or 172.16/12 or 192.168/16))'
```

___

##### Tool: [tcpick](http://tcpick.sourceforge.net/)

###### Analyse packets in real-time

```bash
while true ; do tcpick -a -C -r dump.pcap ; sleep 2 ; clear ; done
```

___

##### Tool: [ngrep](http://ngrep.sourceforge.net/usage.html)

```bash
ngrep -d eth0 "www.domain.com" port 443
```

* `-d [iface|any]` - set interface
* `[domain]` - set hostname
* `port [1-65535]` - set port number

```bash
ngrep -d eth0 "www.domain.com" src host 10.240.20.2 and port 443
```

* `(host [ip|hostname])` - filter by ip or hostname
* `(port [1-65535])` - filter by port number

```bash
ngrep -d eth0 -qt -O ngrep.pcap "www.domain.com" port 443
```

* `-q` - quiet mode (only payloads)
* `-t` - added timestamps
* `-O [filename]` - save output to file, `-I [filename]` - reading from file

```bash
ngrep -d eth0 -qt 'HTTP' 'tcp'
```

* `HTTP` - show http headers
* `tcp|udp` - set protocol
* `[src|dst] host [ip|hostname]` - set direction for specific node

```bash
ngrep -l -q -d eth0 -i "User-Agent: curl*"
```

* `-l` - stdout line buffered
* `-i` - case-insensitive search

___

##### Tool: [hping3](http://www.hping.org/)

```bash
hping3 -V -p 80 -s 5050 www.google.com
```

* `-V|--verbose` - verbose mode
* `-p|--destport` - set destination port
* `-s|--baseport` - set source port
* `` - set scan type
* `-F|--fin` - set FIN flag, port open if no reply
* `-S|--syn` - set SYN flag
* `-P|--push` - set PUSH flag
* `-A|--ack` - set ACK flag (use when ping is blocked, RST response back if the port is open)
* `-U|--urg` - set URG flag
* `-Y|--ymas` - set Y unused flag (0x80 - nullscan), port open if no reply
* `-M 0 -UPF` - set TCP sequence number and scan type (URG+PUSH+FIN), port open if no reply

```bash
hping3 -V -c 1 -1 -C 8 www.google.com
```

* `-c [num]` - packet count
* `-1` - set ICMP mode
* `-C|--icmptype [icmp-num]` - set icmp type (default icmp-echo = 8)

```bash
hping3 -V -c 1000000 -d 120 -S -w 64 -p 80 --flood --rand-source
```

* `--flood` - sent packets as fast as possible (don't show replies)
* `--rand-source` - random source address mode
* `-d --data` - data size
* `-w|--win` - winsize (default 64)

___

##### Tool: [nmap](https://nmap.org/)

###### Ping scans the network

```bash
nmap -sP 192.168.0.0/24
```

###### Show only open ports

```bash
nmap -F --open 192.168.0.0/24
```

###### Full TCP port scan using with service version detection

```bash
nmap -p 1-65535 -sV -sS -T4 192.168.0.0/24
```

###### Nmap scan and pass output to Nikto

```bash
nmap -p80,443 192.168.0.0/24 -oG - | nikto.pl -h -
```

###### Recon specific ip:service with Nmap NSE scripts stack

```bash
# Set variables:
_hosts="192.168.250.10"
_ports="80,443"

# Set Nmap NSE scripts stack:
_nmap_nse_scripts="+dns-brute,\
+http-auth-finder,\
+http-chrono,\
+http-cookie-flags,\
+http-cors,\
+http-cross-domain-policy,\
+http-csrf,\
+http-dombased-xss,\
+http-enum,\
+http-errors,\
+http-git,\
+http-grep,\
+http-internal-ip-disclosure,\
+http-jsonp-detection,\
+http-malware-host,\
+http-methods,\
+http-passwd,\
+http-phpself-xss,\
+http-php-version,\
+http-robots.txt,\
+http-sitemap-generator,\
+http-shellshock,\
+http-stored-xss,\
+http-title,\
+http-unsafe-output-escaping,\
+http-useragent-tester,\
+http-vhosts,\
+http-waf-detect,\
+http-waf-fingerprint,\
+http-xssed,\
+traceroute-geolocation.nse,\
+ssl-enum-ciphers,\
+whois-domain,\
+whois-ip"

# Set Nmap NSE script params:
_nmap_nse_scripts_args="dns-brute.domain=${_hosts},http-cross-domain-policy.domain-lookup=true,"
_nmap_nse_scripts_args+="http-waf-detect.aggro,http-waf-detect.detectBodyChanges,"
_nmap_nse_scripts_args+="http-waf-fingerprint.intensive=1"

# Perform scan:
nmap --script="$_nmap_nse_scripts" --script-args="$_nmap_nse_scripts_args" -p "$_ports" "$_hosts"
```

___

##### Tool: [netcat](http://netcat.sourceforge.net/)

```bash
nc -kl 5000
```

* `-l` - listen for an incoming connection
* `-k` - listening after client has disconnected
* `>filename.out` - save receive data to file (optional)

```bash
nc 192.168.0.1 5051 < filename.in
```

* `< filename.in` - send data to remote host

```bash
nc -vz 10.240.30.3 5000
```

* `-v` - verbose output
* `-z` - scan for listening daemons

```bash
nc -vzu 10.240.30.3 1-65535
```

* `-u` - scan only udp ports

###### Transfer data file (archive)

```bash
server> nc -l 5000 | tar xzvfp -
client> tar czvfp - /path/to/dir | nc 10.240.30.3 5000
```

###### Launch remote shell

```bash
# 1)
server> nc -l 5000 -e /bin/bash
client> nc 10.240.30.3 5000

# 2)
server> rm -f /tmp/f; mkfifo /tmp/f
server> cat /tmp/f | /bin/bash -i 2>&1 | nc -l 127.0.0.1 5000 > /tmp/f
client> nc 10.240.30.3 5000
```

###### Simple file server

```bash
while true ; do nc -l 5000 | tar -xvf - ; done
```

###### Simple minimal HTTP Server

```bash
while true ; do nc -l -p 1500 -c 'echo -e "HTTP/1.1 200 OK\n\n $(date)"' ; done
```

###### Simple HTTP Server

> Restarts web server after each request - remove `while` condition for only single connection.

```bash
cat > index.html << __EOF__








Hello! It's a site.