Book Image

The Web Application Hacker's Handbook

By : Dafydd Stuttard, Marcus Pinto
Book Image

The Web Application Hacker's Handbook

By: Dafydd Stuttard, Marcus Pinto

Overview of this book

Web applications are the front door to most organizations, exposing them to attacks that may disclose personal information, execute fraudulent transactions, or compromise ordinary users. This practical book has been completely updated and revised to discuss the latest step-by-step techniques for attacking and defending the range of ever-evolving web applications. Youíll explore the various new technologies employed in web applications that have appeared since the first edition and review the new attack techniques that have been developed, particularly in relation to the client side. The book starts with the current state of web application security and the trends that indicate how it is likely to evolve soon. Youíll examine the core security problem affecting web applications and the defence mechanisms that applications implement to address this problem, and youíll also explore the key technologies used in todayís web application. Next, youíll carry out tasks for breaking into web applications and for executing a comprehensive attack. As you progress, youíll learn to find vulnerabilities in an application's source code and review the tools that can help when you hack web applications. Youíll also study a detailed methodology for performing a comprehensive and deep attack against a specific target. By the end of this book, youíll be able to discover security flaws in web applications and how to deal with them.
Table of Contents (32 chapters)
Free Chapter
About the Authors
About the Technical Editor
MDSec: The Authors’ Company
End User License Agreement

9 Test for Logic Flaws


Figure 21.10 Testing for logic flaws

9.1 Identify the Key Attack Surface

  1. 9.1.1 Logic flaws can take a huge variety of formsand exist within any aspect of the application's functionality. To ensure that probing for logic flaws is feasible, you should first narrow down the attack surface to a reasonable area for manual testing.
  2. 9.1.2 Review the results of your application mapping exercises, and identify any instances of the following features:
    • Multistage processes
    • Critical security functions, such as login
    • Transitions across trust boundaries (for example, moving from being anonymous to being self-registered to being logged in)
    • Context-based functionality presented to a user
    • Checks and adjustments made to transaction prices or quantities

9.2 Test Multistage Processes

  1. 9.2.1.When a multistage process involves a defined sequence of requests, attempt to submit these requests out of the expected sequence. Try skipping certain stages, accessing a single stage...