VM escape has become a popular topic of discussion over the last few years. A good amount of research on this topic has been published for various hypervisors like VMware, QEMU, VirtualBox, Xen and Hyper-V. Bhyve is a hypervisor for FreeBSD supporting hardware-assisted virtualization. This paper details the exploitation of two bugs in bhyve - FreeBSD-SA-16:32.bhyve [1] (VGA emulation heap overflow) and CVE-2018-17160 [21] (Firmware Configuration device bss buffer overflow) and some generic techniques which could be used for exploiting other bhyve bugs. Further, the paper also discusses sandbox escapes using PCI device passthrough, and Control-Flow Integrity bypasses in HardenedBSD 12-CURRENT

source: grugq