Comment 0 for bug 1530927

By overwriting the disk inside an instance with a malicious
image and requesting a snapshot, an authenticated user would be able to
read an arbitrary file from the compute host. Note that the host file
needs to be readable by the nova user to be exposed except when using
lvm for instance storage, when all files readable by root are exposed.
Only setups using libvirt to spawn instances are vulnerable. Of these,
setups which use filesystem storage, and do not set "use_cow_images =
False" in Nova configuration are not affected. Setups which use ceph or
lvm for instance storage, and setups which use filesystem storage with
"use_cow_images = False" are all affected.

CVE-2015-7548