Race condition in the v9fs_xattrwalk function in hw/9pfs/9p.c in QEMU (aka Quick Emulator) allows local guest OS users to obtain sensitive information from host heap memory via vectors related to reading extended attributes.
Condición de carrera en la función v9fs_xattrwalk en hw/9pfs/9p.c en QEMU (también conocido como Quick Emulator) permite que los usuarios de sistemas operativos invitados locales obtengan información sensible de la memoria dinámica (heap) mediante vectores relacionados con la lectura de atributos extendidos.
USN-3575-1 fixed vulnerabilities in QEMU. The fix for CVE-2017-11334 caused a regression in Xen environments. This update removes the problematic fix pending further investigation. It was discovered that QEMU incorrectly handled guest ram. A privileged attacker inside the guest could use this issue to cause QEMU to crash, resulting in a denial of service. This issue only affected Ubuntu 14.04 LTS and Ubuntu 16.04 LTS. David Buchanan discovered that QEMU incorrectly handled the VGA device. A privileged attacker inside the guest could use this issue to cause QEMU to crash, resulting in a denial of service. This issue was only addressed in Ubuntu 17.10. Thomas Garnier discovered that QEMU incorrectly handled multiboot. An attacker could use this issue to cause QEMU to crash, resulting in a denial of service, or possibly execute arbitrary code on the host. In the default installation, when QEMU is used with libvirt, attackers would be isolated by the libvirt AppArmor profile. This issue only affected Ubuntu 14.04 LTS and Ubuntu 16.04 LTS. Various other issues were also addressed.
