The Book of Secret Knowledge

                            "Knowledge is powerful, be careful how you use it!"
A collection of inspiring lists, manuals, cheat sheets, blogs, hacks, one-liners, cli/web tools, and more.

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CLI Tools 

 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.

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, clustering and synchronizing tmux-sessions.

 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.

 Files and directories

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

 Network

   PuTTY - is an SSH and telnet client, developed originally by Simon Tatham.
   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.
   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 network diagnostic tool.
   mylg - is an open source utility which combines the functions of the different network probes in one diagnostic tool.
   netcat - is a networking utility which reads and writes data across network connections, using the TCP/IP protocol.
   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.
   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.

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 (pDNS at Farsight Security, CIRCL pDNS).
   grimd - fast dns proxy, built to black-hole internet advertisements and malware servers.

 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.
   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.
   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.

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.

 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.

 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.

 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'.
   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 - small utility to 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.

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.

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

 TOR

   Nipe - script to make Tor Network your default gateway.
   multitor - a tool that lets you create multiple TOR instances with a load-balancing.

 Messengers/IRC Clients

   Irssi - is a free open source terminal based IRC client.
   WeeChat - is an extremely extensible and lightweight IRC client.

 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 

 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.

 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.
   JMeter™ - open source software to load test functional behavior and measure performance.
   locust - scalable user load testing tool written in Python.

 Browsers

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

 Password Managers

   KeePassXC - store your passwords safely and auto-type them into your everyday websites and apps.
   Enpass - password manager and secure wallet.

 Messengers/IRC Clients

   HexChat - is an IRC client based on XChat.
   Pidgin - is an easy to use and free chat client used by millions.

 Messengers (end-to-end encryption)

   Signal - is an encrypted communications app.
   Wire - secure messaging, file sharing, voice calls and video conferences. All protected with end-to-end encryption.
   TorChat - decentralized anonymous instant messenger on top of Tor Hidden Services.

 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

 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).

 SSL/Security

   SSLLabs Server Test - free online service performs a deep analysis of the configuration of any SSL web server.
   SSLLabs Server Test (DEV) - free online service 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.
   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? - list of the world's top 100 websites by Alexa rank not automatically redirecting insecure requests.
   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.

 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.

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.
   dnslookup (ceipam) - one of the best DNS propagation checker (and not only).
   What's My DNS - DNS propagation checking tool.

 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.
   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.

 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.

 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, routes 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.
   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.

Privacy

   privacytools.io - 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).

 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. Supports React, Vue, Angular, CxJS, Dojo, etc.
   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.

 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.

 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 - do you use Shodan for everyday work? 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.
   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.
   Hackle - search engine for hackers and security professionals.*
   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.
   scylla - db dumps and more.
   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 - find where any technology is used, across millions of sites.
   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 for the advanced analysis of indicators of compromise.
   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.
   NerdyData - search source code across 65 million websites.
   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.

 Generators

   thispersondoesnotexist - generate fake faces in one click - endless possibilities.
   AI Generated Photos - 100.000 AI generated faces.
   fakeface - fake faces browser.
   Intigriti Redirector - open redirect/SSRF payload generator.

 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.

 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 zero-day exploits and also to sell 0day 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.

 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.

 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.

 Secure Webmail Providers

   CounterMail - is a secure and easy to use 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.

 Crypto

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

 PGP Keyservers

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

Systems/Services 

 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 and security researchers.
   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.

 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.

 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.

 Other Services

   3proxy - tiny free proxy server.

 Security/hardening

   Emerald Onion - is a 501(c)(3) nonprofit organization and transit internet service provider (ISP) based in Seattle.
   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, Shadowsocks, and more.

Networks 

 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.

 Labs

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

 Other

   LBNL's Network Research Group - home page of the Network Research Group (NRG); tools, talks, papers and more.

Containers/Orchestration 

 CLI Tools

   gvisor - container runtime sandbox.
   ctop - top-like interface for container metrics.
   docker-bench-security - is a script that checks for dozens of common best-practices around deploying Docker.

 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.

 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 

 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 and utilities 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.

 Text Editors

   Vim Cheat Sheet - great multi language vim guide.

 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.

Sed & Awk & Other

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

 *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.
   Unix Toolbox - collection of Unix/Linux/BSD commands and tasks which are useful for IT work or for advanced users.
   Linux Guide and Hints - tutorials on system administration in Fedora and CentOS.
   strace-little-book - a little book which introduces strace.
   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 - describes 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.
   PacketLife.net - a place to record notes while studying for Cisco's CCNP certification.

 Microsoft

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

 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.

 System hardening

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

 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.

 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 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 reverse proxies, cache proxies, etc.
   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.

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.

 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?
   poor man's profiler - sampling tools 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.
   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 - an infographics which 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 known to us.
   How to build a 8 GPU password cracker - any "black magic" or 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.
   Five Whys - you know what the problem is, but you cannot solve it?
   howhttps.works - how HTTPS works ...in a comic!
   howdns.works - a fun and colorful explanation of how DNS works.

Inspiring Lists 

 SysOps/DevOps

   Awesome Sysadmin - amazingly awesome open source sysadmin resources.
   Awesome Shell - awesome command-line frameworks, toolkits, guides and gizmos.
   Command-line-text-processing - from finding text to search and replace, from sorting to beautifying text 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 - learn 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 collection of applications 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.
   devops-interview-questions - contains interview questions on various DevOps and SRE related topics.

 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 - the only 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.

 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.
   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.
   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.
   awesome-sec-talks - is a collected list of awesome security talks.
   Movies for Hackers - list of movies every hacker & cyberpunk must watch.

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.

Blogs/Podcasts/Videos 

 SysOps/DevOps

   Varnish for PHP developers - very interesting presentation of Varnish by Mattias Geniar.
   A Netflix Guide to Microservices - Josh Evans talks about the chaotic and vibrant world of microservices at Netflix.

 Developers

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

 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, international 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.

 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.
   PortSwigger Web Security Blog - about web app security vulns and top tips from our team of web security.
   Secjuice - is the only non-profit, independent and volunteer led publication in the information security space.
   Decipher - security news that informs and inspires.

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.

 Geeky Cybersecurity Video Blogs

   rev3rse security - offensive, binary exploitation, web application security, vulnerability, 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.

 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 - chief scientist at White Ops, 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.

Hacking/Penetration Testing  

 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, contains a lot a ready to use exploit.
   Burp Suite - tool for testing web application security, intercepting proxy to replay, inject, scan and fuzz HTTP requests.
   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 and software developers.
   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.
   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 and resource discovery.
   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.
   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.

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 that things I 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.
   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.
   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 engagements.
   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 & computer science 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 information 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 penetration test reports released by several consulting security groups.
   hackso.me - a great journey into security.

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 regarding system exploitation.
   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 and skills.
   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 penetration testing 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!
   OverTheWire - can help you to learn and practice security concepts in the form of fun-filled games.
   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 and research purposes.
   HackThis! - discover how hacks, dumps and defacements are performed and secure your website against hackers.
   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.

Your daily knowledge and news  

 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.

 IRC Channels

   #hackerspaces - hackerspace IRC channels.

 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).

 Other/All-in-one

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

Other Cheat Sheets  

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 command-line 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.

Code Contributors

This project exists thanks to all the people who contribute.

https://github.com/trimstray/the-book-of-secret-knowledge/graphs/contributors?from=2018-06-17&to=2020-01-20&type=d