Building Secure PHP Apps


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Building Secure PHP Apps

is your PHP app truly secure? Let's make sure you get home on time and sleep well at night.

About the Book

Do you ever wonder how vulnerable you are to being hacked?  Do you feel confident about storing your users sensitive information? Imagine feeling confident in the integrity of your software when you store your user's sensitive data.  No more fighting fires with lost data, no more late nights, your application is secure. In this short book I'll give you clear, actionable details on how to secure various parts of your web application.  You will also find scenarios to handle and improve existing legacy issues.

Several years ago I was writing a web application for a client in the CodeIgniter PHP framework, *shudder*, but CodeIgniter didn't include any type of authentication system built in.  I of course did what any good/lazy developer would do and went on the hunt for a well made library to supply authentication capabilities.  To my chagrin I discovered that there weren't any clean, concise libraries that fit my needs for authentication in CodeIgniter.  Thus began my journey of creating Ion Auth, a simple authentication library for CodeIgniter, and a career long crusade for securing web applications as well as helping other developers do the same.

Here we are years later, a lot of us have moved on to other frameworks or languages, but I still repeatedly see basic security being overlooked.  So let's fix that.  I want to make sure that you'll never have to live the horror of leaking user passwords, or have someone inject malicious SQL into your database, or the suite of other "hacks" that could have been easily avoided.  Let's make sure we all get home on time and sleep well at night.


This is a quick read, at just over 100 pages.  This is a handbook style guide to specific items you can act on.  The following sections will be covered:

  • Never trust your users - escape all input
  • HTTPS/SSL/BCA/JWH/SHA and other random letters, some of them actually matter
  • Password Encryption and Storage for Everyone
  • Authentication, Access Control, and Safe File Handing
  • Safe Defaults, Cross Site Scripting and other Popular Hacks


 All code examples are written in PHP with accompanying source code on GitHub.


This book is now 100% complete and ready to school you.  There will be occasional releases for errata and to keep things up to date. 

About the Author
Ben Edmunds

Ben Edmunds leads development teams to create cutting-edge web and mobile applications. He is an active leader, developer, and speaker in various development communities, especially the CodeIgniter and Laravel PHP framework communities. He has been developing software professionally for over 10 years and in that time has worked on everything from robotics to government projects.  

PHP Town Hall podcast co-host.  Portland PHP Usergroup co-organizer.  Open source advocate.

About the Contributors

Aken Roberts
Aken Roberts

Eric "Aken" Roberts is the Director of Application Development at Swarming Technology in Milwaukee, Wisconsin. You can often find him helping out in #Laravel and pinging people on Twitter. Outside of a text editor, he writes and reviews various publications (okay, that's may happen in a text editor, too), plays tennis and drums, collects Hot Wheels, torments his cats, and drinks too much Mountain Dew. And he's getting married in October!

You can find Aken on Twitter @cryode, on GitHub @cryode, or at his website,

David Stanley
David Stanley

Tech Reviewer

father, husband , grunt, geek, triathlete... pretty much in that order. PHP, Python, JS. Co-organizer of the Portland PHP User Group.
Mike Wales
Mike Wales

Tech Reviewer & Grammar Freak

Lead Full Stack Developer. Co-Founder & CTO, Students Gone Global. Founder, WoWCensus. Worked at NSA, DIA, JFCC-Space.

Table of Contents

  • Constructor
    • Format
    • Errata
    • Sample Code
    • About the Author
  • Chapter 1 - Never Trust Your Users. Sanitize ALL Input!
    • SQL Injection
    • Mass Assignment
    • Typecasting
    • Sanitizing Output
  • Chapter Two - HTTPS/SSL/BCA/JWH/SHA and Other Random Letters; Some of Them Actually Matter.
    • What is HTTPS
    • Limitations
    • When to use HTTPS
    • Implementing HTTPS
    • Paths
  • Chapter 3 - Password Encryption and Storage for Everyone
    • The Small Print
    • What is a Hash?
    • Popular Attacks
    • A Pinch of Salt
    • Hashing Algorithms
    • Storage
    • Validation
    • Putting It All Together
    • Brute Force Protection
    • Upgrading Legacy Systems
    • Resources
  • Chapter 4 - Authentication, Access Control, and Safe File Handing
    • Authentication
    • Access Control
    • Validating Redirects
    • Obfuscation
    • Safe File Handing
  • Chapter 5 - Safe Defaults, Cross Site Scripting, and Other Popular Hacks
    • Never Trust Yourself - Use Safe Defaults
    • Never Trust Dynamic Typing. It’s Not Your Friend.
    • Cross Site Scripting
    • Attack Entry Points
    • Cross Site Request Forgery
    • Multiple Form Submits
    • Race Conditions
    • Outdated Libraries / External Programs
  • Destructor
    • About the Author
    • Security Audit / Consulting
  • Notes

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