====================================================================                   Red Hat Security Advisory

Synopsis:          Important: kvm security update
Advisory ID:       RHSA-2015:1003-01
Product:           Red Hat Enterprise Linux
Advisory URL:      https://access.redhat.com/errata/RHSA-2015:1003.html
Issue date:        2015-05-13
CVE Names:         CVE-2015-3456 
====================================================================
1. Summary:

Updated kvm packages that fix one security issue are now available for Red
Hat Enterprise Linux 5.

Red Hat Product Security has rated this update as having Important security
impact. A Common Vulnerability Scoring System (CVSS) base score, which
gives a detailed severity rating, is available from the CVE link in the
References section.

2. Relevant releases/architectures:

RHEL Desktop Multi OS (v. 5 client) - x86_64
RHEL Virtualization (v. 5 server) - x86_64

3. Description:

KVM (Kernel-based Virtual Machine) is a full virtualization solution for
Linux on AMD64 and Intel 64 systems.

An out-of-bounds memory access flaw was found in the way QEMU's virtual
Floppy Disk Controller (FDC) handled FIFO buffer access while processing
certain FDC commands. A privileged guest user could use this flaw to crash
the guest or, potentially, execute arbitrary code on the host with the
privileges of the host's QEMU process corresponding to the guest.
(CVE-2015-3456)

Red Hat would like to thank Jason Geffner of CrowdStrike for reporting
this issue.

All kvm users are advised to upgrade to these updated packages, which
contain a backported patch to correct this issue. Note: The procedure in
the Solution section must be performed before this update will take effect.

4. Solution:

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

For details on how to apply this update, refer to:

https://access.redhat.com/articles/11258

The following procedure must be performed before this update will take
effect:

1) Stop all KVM guest virtual machines.

2) Either reboot the hypervisor machine or, as the root user, remove (using
"modprobe -r [module]") and reload (using "modprobe [module]") all of the
following modules which are currently running (determined using "lsmod"):
kvm, ksm, kvm-intel or kvm-amd.

3) Restart the KVM guest virtual machines.

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

1218611 - CVE-2015-3456 qemu: fdc: out-of-bounds fifo buffer memory access

6. Package List:

RHEL Desktop Multi OS (v. 5 client):

Source:
kvm-83-272.el5_11.src.rpm

x86_64:
kmod-kvm-83-272.el5_11.x86_64.rpm
kmod-kvm-debug-83-272.el5_11.x86_64.rpm
kvm-83-272.el5_11.x86_64.rpm
kvm-debuginfo-83-272.el5_11.x86_64.rpm
kvm-qemu-img-83-272.el5_11.x86_64.rpm
kvm-tools-83-272.el5_11.x86_64.rpm

RHEL Virtualization (v. 5 server):

Source:
kvm-83-272.el5_11.src.rpm

x86_64:
kmod-kvm-83-272.el5_11.x86_64.rpm
kmod-kvm-debug-83-272.el5_11.x86_64.rpm
kvm-83-272.el5_11.x86_64.rpm
kvm-debuginfo-83-272.el5_11.x86_64.rpm
kvm-qemu-img-83-272.el5_11.x86_64.rpm
kvm-tools-83-272.el5_11.x86_64.rpm

These packages are GPG signed by Red Hat for security.  Our key and
details on how to verify the signature are available from
https://access.redhat.com/security/team/key/

7. References:

https://access.redhat.com/security/cve/CVE-2015-3456
https://access.redhat.com/security/updates/classification/#important

8. Contact:

The Red Hat security contact is . More contact
details at https://access.redhat.com/security/team/contact/

Copyright 2015 Red Hat, Inc.