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

Securing Session Management

The defensive measures that web applications must take to prevent attacks on their session management mechanisms correspond to the two broad categories of vulnerability that affect those mechanisms. To perform session management in a secure manner, an application must generate its tokens in a robust way and must protect these tokens throughout their life cycle from creation to disposal.

Generate Strong Tokens

The tokens used to reidentify a user between successive requests should be generated in a manner that does not provide any scope for an attacker who obtains a large sample of tokens from the application in the usual way to predict or extrapolate the tokens issued to other users.

The most effective token generation mechanisms are those that:

  • Use an extremely large set of possible values
  • Contain a strong source of pseudorandomness, ensuring an even and unpredictable spread of tokens across the range of possible values

In principle, any item of arbitrary...