Tag: 2018

Given the popularity of GDI Bitmap objects for exploitation of kernel vulnerabilities -due to the fact that almost any kind of memory corruption vulnerability (except for NULL-writes) could be used to reliably gain arbitrary R/W primitives over the kernel memory by abusing Bitmaps- Microsoft decided to kill exploitation techniques based on Bitmaps. In order to do this, Windows 10 Fall Creators Update (also known as Windows 10 1709) introduced the Type Isolation feature, an exploitation mitigation in the Win32k subsystem, which splits the memory layout of SURFACE objects, the internal representation of Bitmaps on the kernel side. This blogpost takes a deep dive into the details of how Type Isolation is implemented.

This article aims to presentby analyzing an obfuscated binary using QBDI, thus showcasing some of the nice features it offers. This blog post was written last year during my internship at Quarkslab, where I discovered the wonderful (but not so simple) world of Dynamic Binary Instrumentation.

What happens if one builds up on the Spectre vulnerability to implement a convoluted version of memcpy? From an obfuscator point-of-view, it unleashes a wide range of opportunities, which turn a definite bug into a fun[nk]y feature.