14 DAY TRIAL // A single Cinder vulnerability has been found and repaired in Ubuntu 15.04 (Vivid Vervet) and a new patch has been made available in the official repositories.
Cinder is the OpenStack storage service, so unless they're using OpenStack in any way, this should not affect regular users directly. Even so, it's a good idea to upgrade the operating system in order to plug any kind of exploit of the vulnerability identified by developers.
"Bastian Blank discovered that Cinder guessed image formats based on untrusted data. An attacker could use this to read arbitrary files from the Cinder host," said the maintainers in the security notification.
For a more detailed description of the issues, you can see Canonical's security notification. Users should upgrade their Linux distribution in order to correct this issue. The vulnerability can be fixed if you upgrade your system(s) to the latest python-cinder package specific to each distribution. To apply the patch, users can simply run the Update Manager application.
If you don't want to use the Software Updater, you can open a terminal and enter the following commands (you will need to be root):
sudo apt-get dist-upgrade