In this presentation, we explore the attack surface of modern hypervisors from the perspective of vulnerabilities in system firmware, such as BIOS and in hardware emulation. We will demonstrate a number of new attacks on hypervisors based on system firmware vulnerabilities with impacts ranging from VMM DoS to hypervisor privilege escalation to SMM privilege escalation from within the virtual machines.
We will also show how a firmware rootkit based on these vulnerabilities could expose secrets within virtual machines and explain how firmware issues can be used for analysis of hypervisor-protected content such as VMCS structures, EPT tables, host physical addresses (HPA) map, IOMMU page tables etc. To enable further hypervisor security testing, we will also be releasing new modules in the open source CHIPSEC framework to test issues in hypervisors when virtualizing hardware.