WINDOWS 10 SEGMENT HEAP INTERNALS presented at blackhatUS 2016

by Mark Vincent Yason,

Summary : Introduced in Windows 10, Segment Heap is the native heap used in Windows app (formerly called Modern/Metro app) processes and certain system processes. This heap is an addition to the well-researched and widely documented NT heap that is still used in traditional application processes and in certain types of allocations in Windows app processes.
One important aspect of the Segment Heap is that it is enabled for Microsoft Edge which means that components/dependencies running in Edge that do not use a custom heap manager will use the Segment Heap. Therefore, reliably exploiting memory corruption vulnerabilities in these Edge components/dependencies would require some level of understanding of the Segment Heap.
In this presentation, I'll discuss the data structures, algorithms and security mechanisms of the Segment Heap. Knowledge of the Segment Heap is also applied by discussing and demonstrating how a memory corruption vulnerability in the Microsoft WinRT PDF library (CVE-2016-0117) is used to create a reliable write primitive in the context of the Edge content process.