NEW VMSCAPE ATTACK BREAKS GUEST-HOST ISOLATION ON AMD, INTEL CPUS

Summary from the TLDR InfoSec newsletter

Researchers from ETH-Zurich have found a new attack that allows an attacker to leak cryptographic keys from an unmodified QEMU hypervisor process running on modern AMD or Intel CPUs. In the attack, a guest user can influence indirect branch prediction in a host user process to leak arbitrary memory at a rate of 32 bytes/second with a byte-level accuracy of 98.7%. AMD has released a security bulletin about the issue. Linux kernel developers have released patches to mitigate the problem.