Hacking Exposed ™ Web 2.0 Reviews “In the hectic rush to build Web 2.0 applications, developers continue to forget about security or, at best, treat it as an afterthought. Don’t risk your customer data or the integrity of your product; learn from this book and put a plan in place to secure your Web 2.0 applications.” —Michael Howard Principal Security Program Manager, Microsoft Corp. “This book concisely identifies the types of attacks which are faced daily by Web 2.0 sites. The authors give solid, practical advice on how to identify and mitigate these threats. This book provides valuable insight not only to security engineers, but to application developers and quality assurance engineers in your organization.” —Max Kelly, CISSP, CIPP, CFCE Sr. Director, Security Facebook “This book could have been titled Defense Against the Dark Arts as in the Harry Potter novels. It is an insightful and indispensable compendium of the means by which vulnerabilities are exploited in networked computers. If you care about security, it belongs on your bookshelf.” —Vint Cerf Chief Internet Evangelist, Google “Security on the Web is about building applications correctly, and to do so developers need knowledge of what they need to protect against and how. If you are a web developer, I strongly recommend that you take the time to read and understand how to apply all of the valuable topics covered in this book.” —Arturo Bejar Chief Security Officer at Yahoo! “This book gets you started on the long path toward the mastery of a remarkably complex subject and helps you organize practical and in-depth information you learn along the way.” —From the Foreword by Michal Zalewski, White Hat Hacker and Computer Security Expert This page intentionally left blank HACKING EXPOSED™ WEB 2.0: WEB 2.0 SECURITY SECRETS AND SOLUTIONS RICH CANNINGS HIMANSHU DWIVEDI ZANE LACKEY New York Chicago San Francisco Lisbon London Madrid Mexico City Milan New Delhi San Juan Seoul Singapore Sydney Toronto Copyright © 2008 by The McGraw-Hill Companies. All rights reserved. Manufactured in the United States of America. 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I dedicate this book to sprout! <3 —Rich Cannings This book is dedicated to my daughter, Sonia Raina Dwivedi, whose neverending smiles are the best thing a Dad could ask for. —Himanshu Dwivedi To my parents, who always encouraged me and taught me everything I know about cheesy dedications. —Zane Lackey ABOUT THE AUTHORS Rich Cannings Rich Cannings is a senior information security engineer at Google. Prior to working for Google, Rich was an independent security consultant and OpenBSD hacker. Rich holds a joint MSc. in theoretical mathematics and computer science from the University of Calgary. Himanshu Dwivedi Himanshu Dwivedi is a founding partner of iSEC Partners, an information security organization. Himanshu has more than 12 years’ experience in security and information technology. Before forming iSEC, Himanshu was the technical director of @stake’s Bay Area practice. Himanshu leads product development at iSEC Partners, which includes a repertoire of SecurityQA products for web applications and Win32 programs. In addition to his product development efforts, he focuses on client management, sales, and next genera- tion technical research. He has published five books on security, including Hacking Exposed: Web 2.0 (McGraw-Hill), Hacking VoIP (No Starch Press), Hacker’s Challenge 3 (McGraw-Hill), Securing Storage (Addison Wesley Publishing), and Implementing SSH (Wiley Publishing). Himanshu also has a patent pending on a storage design architecture in Fibre Channel SANs VoIP. Zane Lackey Zane Lackey is a senior security consultant with iSEC Partners, an information security organization. Zane regularly performs application penetration testing and code reviews for iSEC. His research focus includes AJAX web applications and VoIP security. Zane has spoken at top security conferences including BlackHat 2006/2007 and Toorcon. Additionally, he is a coauthor of Hacking Exposed: Web 2.0 (McGraw-Hill) and contributing author of Hacking VoIP (No Starch Press). Prior to iSEC, Zane focused on Honeynet research at the University of California, Davis, Computer Security Research Lab, under noted security researcher Dr. Matt Bishop. ABOUT THE CONTRIBUTING AUTHORS Chris Clark Chris Clark possesses several years of experience in secure application design, penetra- tion testing, and security process management. Most recently, Chris has been working for iSEC Partners performing application security reviews of Web and Win32 applications. Chris has extensive experience in developing and delivering security training for large organizations, software engineering utilizing Win32 and the .Net Framework, and ana- lyzing threats to large scale distributed systems. Prior to working for iSEC Partners, Chris worked at Microsoft, assisting several product groups in following Microsoft’s Secure Development Lifecycle. Alex Stamos Alex Stamos is a founder and VP of professional services at iSEC Partners, an information security organization. Alex is an experienced security engineer and consultant specializing in application security and securing large infrastructures, and he has taught multiple classes in network and application security. He is a leading researcher in the field of web application and web services security and has been a featured speaker at top industry conferences such as Black Hat, CanSecWest, DefCon, Syscan, Microsoft BlueHat, and OWASP App Sec. He holds a BSEE from the University of California, Berkeley. ABOUT THE TECHNICAL EDITOR Jesse Burns Jesse Burns is a founding partner and VP of research at iSEC Partners, where he performs penetration tests, writes tools, and leads research. Jesse has more than a decade of experience as a software engineer and security consultant, and he has helped many of the industry’s largest and most technically-demanding companies with their application security needs. He has led numerous development teams as an architect and team lead; in addition, he designed and developed a Windows-delegated enterprise directory management system, produced low-level security tools, built trading and support systems for a major US brokerage, and architected and built large frameworks to support security features such as single sign-on. Jesse has also written network applications such as web spiders and heuristic analyzers. Prior to iSEC, Jesse was a managing security architect at @stake. Jesse has presented his research throughout the United States and internationally at venues including the Black Hat Briefings, Bellua Cyber Security, Syscan, OWASP, Infragard, and ISACA. He has also presented custom research reports for his many security consulting clients on a wide range of technical issues, including cryptographic attacks, fuzzing techniques, and emerging web application threats.