San Francisco, CA, November 9, 2011—Modern web applications are built on a tangle of technologies developed over time and haphazardly patched together. Every piece of the web application stack, from HTTP requests to browser-side scripts, is riddled with important yet subtle security gotchas that developers need to understand in order to keep users safe online.

In The Tangled Web (No Starch Press, November 2011, 320 pp., $49.95, ISBN 9781593273880), Michal Zalewski, one of the world's top security experts and author of Google's Browser Security Handbook, explains how browsers work and why they're fundamentally insecure. Rather than simply list known vulnerabilities, Zalewski examines the entire browser security model, revealing weak points and providing crucial information for shoring up web application security. The book opens with a comprehensive examination of browser mechanisms, the historical reasons behind their design, and the security consequences involved. After examining and dissecting the security mechanisms available for web applications, Zalewski outlines anticipated future developments in browser security, including planned HTML5 features.

"Since Silence on the Wire, readers have been waiting for Zalewski's next book," said No Starch Press Founder Bill Pollock. "As applications migrate to the Web, exposing our private data to a wide range of attacks, the security community is badly in need of instruction on how to make web applications more secure. Zalewski offers real insight."

Readers of The Tangled Web will learn how to:

• Perform common but surprisingly complex tasks such as URL parsing and HTML sanitization
• Use modern security features like Strict Transport Security, Content Security Policy, and Cross-Origin Resource Sharing
• Leverage many variants of the same-origin policy to safely compartmentalize complex web applications and protect user credentials in case of XSS bugs
• Build mashups and embed gadgets without getting stung by the tricky frame navigation policy
• Embed or host user-supplied content without running into the trap of content sniffing

The Tangled Web will prove indispensable to web developers and security researchers who want to create secure web applications that stand the test of time and the savviest of attackers.