(RHSA-2009:0382) Moderate: libvirt security update

libvirt is a C API for managing and interacting with the virtualization
capabilities of Linux and other operating systems. libvirt also provides
tools for remotely managing virtualized systems.

The libvirtd daemon was discovered to not properly check user connection
permissions before performing certain privileged actions, such as
requesting migration of an unprivileged guest domain to another system. A
local user able to establish a read-only connection to libvirtd could use
this flaw to perform actions that should be restricted to read-write
connections. (CVE-2008-5086)

libvirt_proxy, a setuid helper application allowing non-privileged users to
communicate with the hypervisor, was discovered to not properly validate
user requests. Local users could use this flaw to cause a stack-based
buffer overflow in libvirt_proxy, possibly allowing them to run arbitrary
code with root privileges. (CVE-2009-0036)

All users are advised to upgrade to these updated packages, which contain
backported patches which resolve these issues. After installing the update,
libvirtd must be restarted manually (for example, by issuing a “service
libvirtd restart” command), and guest systems rebooted, for this change to
take effect.