14 DAY TRIAL // Three QEMU vulnerabilities have been found and corrected in Ubuntu 15.04 and Ubuntu 14.04 LTS operating systems by Canonical.
QEMU is defined as a machine emulator and virtualizer. It's a tool that can be used to emulate and run other operating systems, so it's important to make sure that things are in tip-top shape. Even if you don't use Qemu, upgrading the system to fix any kind of vulnerabilities is always a good idea.
"Zhu Donghai discovered that QEMU incorrectly handled the SCSI driver. A malicious guest could use this issue to cause a denial of service, or possibly execute arbitrary code on the host as the user running the QEMU process. In the default installation, when QEMU is used with libvirt, attackers would be isolated by the libvirt AppArmor profile. This issue only affected Ubuntu 15.04," reads the security notice.
More details about the QEMU exploits can be found in the official security notice. Users have been advised to upgrade their system as soon as possible. That can be done in a couple of ways, either with the Software Update or from the terminal. In any case, users won't have to reboot their system in order to complete the process. The procedure is the same for all the supported Ubuntu OSes.