Ubuntu Security Notice 2395-1 – Nadav Amit reported that the KVM (Kernel Virtual Machine) mishandles noncanonical addresses when emulating instructions that change the rip (Instruction Pointer). A guest user with access to I/O or the MMIO can use this flaw to cause a denial of service (system crash) of the guest. A flaw was discovered with the handling of the invept instruction in the KVM (Kernel Virtual Machine) subsystem of the Linux kernel. An unprivileged guest user could exploit this flaw to cause a denial of service (system crash) on the guest. Various other issues were also addressed.