Awesome AppSec 
A curated list of resources for learning about application security. Contains books, websites, blog posts, and self-assessment quizzes.
Maintained by Paragon Initiative Enterprises with contributions from the application security and developer communities. We also have other community projects which might be useful for tomorrow's application security experts.
If you are an absolute beginner to the topic of software security, you may benefit from reading A Gentle Introduction to Application Security.
Contributing
Please refer to the contributing guide for details.
Application Security Learning Resources
- General
- Articles
- Books
- Web Application Hacker's Handbook (2011)
- Cryptography Engineering (2010)
- Securing DevOps (2018)
- Gray Hat Python: Programming for Hackers and Reverse Engineers (2009)
- The Art of Software Security Assessment: Identifying and Preventing Software Vulnerabilities (2006)
- C Interfaces and Implementations: Techniques for Creating Reusable Software (1996)
- Reversing: Secrets of Reverse Engineering (2005)
- JavaScript: The Good parts (2008)
- Windows Internals: Including Windows Server 2008 and Windows Vista, Fifth Edition (2007)
- The Mac Hacker's Handbook (2009)
- The IDA Pro Book: The Unofficial Guide to the World's Most Popular Disassembler (2008)
- Internetworking with TCP/IP Vol. II: ANSI C Version: Design, Implementation, and Internals (3rd Edition) (1998)
- Network Algorithmics,: An Interdisciplinary Approach to Designing Fast Networked Devices (2004)
- Computation Structures (MIT Electrical Engineering and Computer Science) (1989)
- Surreptitious Software: Obfuscation, Watermarking, and Tamperproofing for Software Protection (2009)
- Secure Programming HOWTO (2015)
- Security Engineering - Second Edition (2008)
- Bulletproof SSL and TLS (2014)
- Holistic Info-Sec for Web Developers (Fascicle 0) (2016)
- Holistic Info-Sec for Web Developers (Fascicle 1)
- Web Application Hacker's Handbook (2011)
- Classes
- Websites
- AWS Lambda
- Android
- C
- C++
- C Sharp
- Clojure
- Repositories
- Clojure OWASP (2020)
- Repositories
- Go
- Java
- Node.js
- PHP
- Articles
- It's All About Time (2014)
- Secure Authentication in PHP with Long-Term Persistence (2015)
- 20 Point List For Preventing Cross-Site Scripting In PHP (2013)
- 25 PHP Security Best Practices For Sys Admins (2011)
- PHP data encryption primer (2014)
- Preventing SQL Injection in PHP Applications - the Easy and Definitive Guide (2014)
- You Wouldn't Base64 a Password - Cryptography Decoded (2015)
- A Guide to Secure Data Encryption in PHP Applications (2015)
- The 2018 Guide to Building Secure PHP Software (2017)
- Books and ebooks
- Useful libraries
- Websites
- Articles
- Perl
- Python
- Ruby
General
Articles
How to Safely Generate a Random Number (2014)
Released: February 25, 2014
Advice on cryptographically secure pseudo-random number generators.
Salted Password Hashing - Doing it Right (2014)
Released: August 6, 2014
A post on Crackstation, a project by Defuse Security
A good idea with bad usage: /dev/urandom (2014)
Released: May 3, 2014
Mentions many ways to make /dev/urandom fail on Linux/BSD.
Why Invest in Application Security? (2015)
Released: June 21, 2015
Running a business requires being cost-conscious and minimizing unnecessary spending. The benefits of ensuring in the security of your application are invisible to most companies, so often times they neglect to invest in secure software development as a cost-saving measure. What these companies don't realize is the potential cost (both financial and to brand reputation) a preventable data compromise can incur.
The average data breach costs millions of dollars in damage.
Investing more time and personnel to develop secure software is, for most companies, worth it to minimize this unnecessary risk to their bottom line.
Be wary of one-time pads and other crypto unicorns (2015)
Released: March 25, 2015
A must-read for anyone looking to build their own cryptography features.
Books
Web Application Hacker's Handbook (2011)
Released: September 27, 2011
Great introduction to Web Application Security; though slightly dated.
Cryptography Engineering (2010)
Released: March 15, 2010
Develops a sense of professional paranoia while presenting crypto design techniques.
Securing DevOps (2018)
Released: March 1, 2018
Securing DevOps explores how the techniques of DevOps and Security should be applied together to make cloud services safer. This introductory book reviews state of the art practices used in securing web applications and their infrastructure, and teaches you techniques to integrate security directly into your product.
Gray Hat Python: Programming for Hackers and Reverse Engineers (2009)
Released: May 3, 2009
The Art of Software Security Assessment: Identifying and Preventing Software Vulnerabilities (2006)
Released: November 30, 2006
C Interfaces and Implementations: Techniques for Creating Reusable Software (1996)
Released: August 30, 1996
Reversing: Secrets of Reverse Engineering (2005)
Released: April 15, 2005
JavaScript: The Good parts (2008)
Released: May 1, 2008
Windows Internals: Including Windows Server 2008 and Windows Vista, Fifth Edition (2007)
Released: June 17, 2007
The Mac Hacker's Handbook (2009)
Released: March 3, 2009
The IDA Pro Book: The Unofficial Guide to the World's Most Popular Disassembler (2008)
Released: August 22, 2008
Internetworking with TCP/IP Vol. II: ANSI C Version: Design, Implementation, and Internals (3rd Edition) (1998)
Released: June 25, 1998
Network Algorithmics,: An Interdisciplinary Approach to Designing Fast Networked Devices (2004)
Released: December 29, 2004
Computation Structures (MIT Electrical Engineering and Computer Science) (1989)
Released: December 13, 1989
Surreptitious Software: Obfuscation, Watermarking, and Tamperproofing for Software Protection (2009)
Released: August 3, 2009
Secure Programming HOWTO (2015)
Released: March 1, 2015
Security Engineering - Second Edition (2008)
Released: April 14, 2008
Bulletproof SSL and TLS (2014)
Released: August 1, 2014
Holistic Info-Sec for Web Developers (Fascicle 0) (2016)
Released: September 17, 2016
The first part of a three part book series providing broad and in-depth coverage on what web developers and architects need to know in order to create robust, reliable, maintainable and secure software, networks and other, that are delivered continuously, on time, with no nasty surprises.
Holistic Info-Sec for Web Developers (Fascicle 1)
The second part of a three part book series providing broad and in-depth coverage on what web developers and architects need to know in order to create robust, reliable, maintainable and secure software, VPS, networks, cloud and web applications, that are delivered continuously, on time, with no nasty surprises.
Classes
Offensive Computer Security (CIS 4930) FSU
A vulnerability research and exploit development class by Owen Redwood of Florida State University.
Be sure to check out the lectures!
Hack Night
Developed from the materials of NYU Poly's old Penetration Testing and Vulnerability Analysis course, Hack Night is a sobering introduction to offensive security. A lot of complex technical content is covered very quickly as students are introduced to a wide variety of complex and immersive topics over thirteen weeks.
Websites
Hack This Site!
Learn about application security by attempting to hack this website.
Enigma Group
Where hackers and security experts come to train.
Web App Sec Quiz
Self-assessment quiz for web application security
SecurePasswords.info
Secure passwords in several languages/frameworks.
Security News Feeds Cheat-Sheet
A list of security news sources.
Open Security Training
Video courses on low-level x86 programming, hacking, and forensics.
MicroCorruption
Capture The Flag - Learn Assembly and Embedded Device Security
The Matasano Crypto Challenges
A series of programming exercises for teaching oneself cryptography by Matasano Security. The introduction by Maciej Ceglowski explains it well.
PentesterLab
PentesterLab provides free Hands-On exercises and a bootcamp to get started.
Juice Shop
An intentionally insecure Javascript Web Application.
Supercar Showdown
How to go on the offence before online attackers do.
OWASP NodeGoat
Purposly vulnerable to the OWASP Top 10 Node.JS web application, with tutorials, security regression testing with the OWASP Zap API, docker image. With several options to get up and running fast.
Securing The Stack
Bi-Weekly Appsec Tutorials
OWASP ServerlessGoat
OWASP ServerlessGoat is a deliberately insecure realistic AWS Lambda serverless application, maintained by OWASP and created by PureSec. You can install WebGoat, learn about the vulnerabilities, how to exploit them, and how to remediate each issue. The project also includes documentation explaining the issues and how they should be remediated with best-practices.
Blogs
Crypto Fails
Showcasing bad cryptography
NCC Group - Blog
The blog of NCC Group, formerly Matasano, iSEC Partners, and NGS Secure.
Scott Helme
Learn about security and performance.
Cossack Labs blog (2018)
Released: July 30, 2018
Blog of cryptographic company that makes open-source libraries and tools, and describes practical data security approaches for applications and infrastructures.
Wiki pages
OWASP Top Ten Project
The top ten most common and critical security vulnerabilities found in web applications.
Tools
Qualys SSL Labs
The infamous suite of SSL and TLS tools.
securityheaders.io
Quickly and easily assess the security of your HTTP response headers.
report-uri.io
A free CSP and HPKP reporting service.
clickjacker.io
Test and learn Clickjacking. Make clickjacking PoC, take screenshot and share link. You can test HTTPS, HTTP, intranet & internal sites.
AWS Lambda
Tools
PureSec FunctionShield
FunctionShield is a 100% free AWS Lambda security and Google Cloud Functions security library that equips developers with the ability to easily enforce strict security controls on serverless runtimes.
Android
Books and ebooks
SEI CERT Android Secure Coding Standard (2015)
Released: February 24, 2015
A community-maintained Wiki detailing secure coding standards for Android development.
C
Books and ebooks
SEI CERT C Coding Standard (2006)
Released: May 24, 2006
A community-maintained Wiki detailing secure coding standards for C programming.
Defensive Coding: A Guide to Improving Software Security by the Fedora Security Team (2022)
Released: May 23, 2022
Provides guidelines for improving software security through secure coding. Covers common programming languages and libraries, and focuses on concrete recommendations.
C++
Books and ebooks
SEI CERT C++ Coding Standard (2006)
Released: July 18, 2006
A community-maintained Wiki detailing secure coding standards for C++ programming.
C Sharp
Books and ebooks
Security Driven .NET (2015)
Released: July 14, 2015
An introduction to developing secure applications targeting version 4.5 of the .NET Framework, specifically covering cryptography and security engineering topics.
Clojure
Repositories
Clojure OWASP (2020)
Released: May 5, 2020
Repository with Clojure examples of OWASP top 10 vulnerabilities.
Go
Articles
Memory Security in Go - spacetime.dev (2017)
Released: August 3, 2017
A guide to managing sensitive data in memory.
Java
Books and ebooks
SEI CERT Java Coding Standard (2007)
Released: January 12, 2007
A community-maintained Wiki detailing secure coding standards for Java programming.
Secure Coding Guidelines for Java SE (2014)
Released: April 2, 2014
Secure Java programming guidelines straight from Oracle.
Node.js
Articles
Node.js Security Checklist - Rising Stack Blog (2015)
Released: October 13, 2015
Covers a lot of useful information for developing secure Node.js applications.
Awesome Electron.js hacking & pentesting resources (2020)
Released: June 17, 2020
A curated list of resources to secure Electron.js-based applications.
Books and ebooks
Essential Node.js Security (2017)
Released: July 19, 2017
Hands-on and abundant with source code for a practical guide to Securing Node.js web applications.
Training
Security Training by ^Lift Security
Learn from the team that spearheaded the Node Security Project
Security Training from BinaryMist
We run many types of info-sec security training, covering Physical, People, VPS, Networs, Cloud, Web Applications. Most of the content is sourced from the book series Kim has been working on for several years. More info can be found here
PHP
Articles
It's All About Time (2014)
Released: November 28, 2014
A gentle introduction to timing attacks in PHP applications
Secure Authentication in PHP with Long-Term Persistence (2015)
Released: April 21, 2015
Discusses password policies, password storage, "remember me" cookies, and account recovery.
20 Point List For Preventing Cross-Site Scripting In PHP (2013)
Released: April 22, 2013
Padriac Brady's advice on building software that isn't vulnerable to XSS
25 PHP Security Best Practices For Sys Admins (2011)
Released: November 23, 2011
Though this article is a few years old, much of its advice is still relevant as we veer around the corner towards PHP 7.
PHP data encryption primer (2014)
Released: June 16, 2014
@timoh6 explains implementing data encryption in PHP
Preventing SQL Injection in PHP Applications - the Easy and Definitive Guide (2014)
Released: May 26, 2014
TL;DR - don't escape, use prepared statements instead!
You Wouldn't Base64 a Password - Cryptography Decoded (2015)
Released: August 7, 2015
A human-readable overview of commonly misused cryptography terms and fundamental concepts, with example code in PHP.
If you're confused about cryptography terms, start here.
A Guide to Secure Data Encryption in PHP Applications (2015)
Released: August 2, 2015
Discusses the importance of end-to-end network-layer encryption (HTTPS) as well as secure encryption for data at rest, then introduces the specific cryptography tools that developers should use for specific use cases, whether they use libsodium, Defuse Security's secure PHP encryption library, or OpenSSL.
The 2018 Guide to Building Secure PHP Software (2017)
Released: December 12, 2017
This guide should serve as a complement to the e-book, PHP: The Right Way, with a strong emphasis on security and not general PHP programmer topics (e.g. code style).
Books and ebooks
Securing PHP: Core Concepts
Securing PHP: Core Concepts acts as a guide to some of the most common security terms and provides some examples of them in every day PHP.
Using Libsodium in PHP Projects
You shouldn't need a Ph.D in Applied Cryptography to build a secure web application. Enter libsodium, which allows developers to develop fast, secure, and reliable applications without needing to know what a stream cipher even is.
Useful libraries
defuse/php-encryption
Symmetric-key encryption library for PHP applications. (Recommended over rolling your own!)
ircmaxell/password_compat
If you're using PHP 5.3.7+ or 5.4, use this to hash passwords
ircmaxell/RandomLib
Useful for generating random strings or numbers
thephpleague/oauth2-server
A secure OAuth2 server implementation
paragonie/random_compat
PHP 7 offers a new set of CSPRNG functions: random_bytes() and random_int(). This is a community effort to expose the same API in PHP 5 projects (forward compatibility layer). Permissively MIT licensed.
psecio/gatekeeper
A secure authentication and authorization library that implements Role-Based Access Controls and Paragon Initiative Enterprises' recommendaitons for secure "remember me" checkboxes.
openwall/phpass
A portable public domain password hashing framework for use in PHP applications.
Websites
websec.io
websec.io is dedicated to educating developers about security with topics relating to general security fundamentals, emerging technologies and PHP-specific information
Blogs
Paragon Initiative Enterprises Blog
The blog of our technology and security consulting firm based in Orlando, FL
ircmaxell's blog
A blog about PHP, Security, Performance and general web application development.
PΓ‘draic Brady's Blog
PΓ‘draic Brady is a Zend Framework security expert
Mailing lists
Securing PHP Weekly
A weekly newsletter about PHP, security, and the community.
Perl
Books and ebooks
SEI CERT Perl Coding Standard (2011)
Released: January 10, 2011
A community-maintained Wiki detailing secure coding standards for Perl programming.
Python
Books and ebooks
Python chapter of Fedora Defensive Coding Guide
Lists standard library features that should be avoided, and references sections of other chapters that are Python-specific.
Black Hat Python: Python Programming for Hackers and Pentesters
Black Hat Python by Justin Seitz from NoStarch Press is a great book for the offensive security minds
Violent Python
Violent Python shows you how to move from a theoretical understanding of offensive computing concepts to a practical implementation.
Websites
OWASP Python Security Wiki (2014)
Released: June 21, 2014
A wiki maintained by the OWASP Python Security project.
Ruby
Books and ebooks
Secure Ruby Development Guide (2014)
Released: March 10, 2014
A guide to secure Ruby development by the Fedora Security Team. Also available on Github.