Red Hat Security Advisory 2016-0018-01 – OpenStack Compute launches and schedules large networks of virtual machines, creating a redundant and scalable cloud computing platform. Compute provides the software, control panels, and APIs required to orchestrate a cloud, including running virtual machine instances and controlling access through users and projects. A flaw was discovered in the OpenStack Compute snapshot feature when using the libvirt driver. A compute user could overwrite an attached instance disk with a malicious header specifying a backing file, and then request a snapshot, causing a file from the compute host to be leaked. This flaw only affects LVM or Ceph setups, or setups using filesystem storage with “use_cow_images = False”.