Microsoft Gazelle: Internet Browser & Multi-Principal OS Construction

The browser, called Gazelle, relies on a "browser kernel" (5,000 lines of C# code) that helps enforce security rules to prevent malicious access to the PC's underlying operating system.

Gazelle's Browser Kernel is an operating system that exclusively manages resource protection and sharing across web site principals. This construction exposes intricate design issues that no previous work has identified, such as legacy protection of cross-origin script source, and cross-principal, cross-process display and events protection. "Gazelle is different from some other browsers in that it considers each part of a Web site, such as iframes, subframes and plug-ins, as separate elements. Sometimes those elements can pull in malicious content from other Web sites. Google's Chrome runs a Web page and its elements in a single process."