6.8 - RHSA-2014:0103

Problem Description:

Updated libvirt packages that fix two security issues and one bug are now available for Red Hat Enterprise Linux 6.

The Red Hat Security Response Team has rated this update as having moderate security impact. Common Vulnerability Scoring System (CVSS) base scores, which give detailed severity ratings, are available for each vulnerability from the CVE links in the References section.

2. Relevant releases/architectures:

Red Hat Enterprise Linux Desktop (v. 6) - i386, x86_64 Red Hat Enterprise Linux Desktop Optional (v. 6) - i386, x86_64 Red Hat Enterprise Linux HPC Node (v. 6) - x86_64 Red Hat Enterprise Linux HPC Node Optional (v. 6) - x86_64 Red Hat Enterprise Linux Server (v. 6) - i386, ppc64, s390x, x86_64 Red Hat Enterprise Linux Server Optional (v. 6) - x86_64 Red Hat Enterprise Linux Workstation (v. 6) - i386, x86_64 Red Hat Enterprise Linux Workstation Optional (v. 6) - x86_64

3. Description:

The libvirt library is a C API for managing and interacting with the virtualization capabilities of Linux and other operating systems. In addition, libvirt provides tools for remote management of virtualized systems.

A use-after-free flaw was found in the way several libvirt block APIs handled domain jobs. A remote attacker able to establish a read-only connection to libvirtd could use this flaw to crash libvirtd or, potentially, execute arbitrary code with the privileges of the libvirtd process (usually root). (CVE-2013-6458)

A race condition was found in the way libvirtd handled keepalive initialization requests when the connection was closed prior to establishing connection credentials. An attacker able to establish a read-only connection to libvirtd could use this flaw to crash libvirtd, resulting in a denial of service. (CVE-2014-1447)

This update also fixes the following bug:

* A race condition was possible between a thread starting a virtual machine with a guest agent configured (regular start-up or while migrating) and a thread that was killing the VM process (or the process crashing). The race could cause the monitor object to be freed by the thread that killed the VM process, which was later accessed by the thread that was attempting to start the VM, resulting in a crash. This issue was fixed by checking the state of the VM after the attempted connection to the guest agent; if the VM in the meantime exited, no other operations are attempted. (BZ#1055578)

All libvirt users are advised to upgrade to these updated packages, which contain backported patches to correct these issues. After installing the updated packages, libvirtd will be restarted automatically.

4. Solution:

Before applying this update, make sure all previously released errata relevant to your system have been applied.

This update is available via the Red Hat Network. Details on how to use the Red Hat Network to apply this update are available at https://access.redhat.com/site/articles/11258

5. Bugs fixed (https://bugzilla.redhat.com/):

1048631 - CVE-2013-6458 qemu: job usage issue in several APIs leading to libvirtd crash 1052957 - CVE-2014-1447 libvirt: denial of service with keepalive 1055578 - bidirectional VMs migration between 2 hosts fail on VM doesn't exist / fatal error