RHSA-2015:1508 - Security Advisory

Topic

Updated qemu-kvm-rhev packages that fix two security issues are now
available for Red Hat Enterprise Virtualization Hypervisor 7.

Red Hat Product Security has rated this update as having Important 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.

Description

KVM (Kernel-based Virtual Machine) is a full virtualization solution for
Linux on AMD64 and Intel 64 systems. The qemu-kvm-rhev package provides the
user-space component for running virtual machines using KVM.

A heap buffer overflow flaw was found in the way QEMU's IDE subsystem
handled I/O buffer access while processing certain ATAPI commands.
A privileged guest user in a guest with the CDROM drive enabled could
potentially use this flaw to execute arbitrary code on the host with the
privileges of the host's QEMU process corresponding to the guest.
(CVE-2015-5154)

An out-of-bounds memory access flaw, leading to memory corruption or
possibly an information leak, was found in QEMU's pit_ioport_read()
function. A privileged guest user in a QEMU guest, which had QEMU PIT
emulation enabled, could potentially, in rare cases, use this flaw to
execute arbitrary code on the host with the privileges of the hosting QEMU
process. (CVE-2015-3214)

Red Hat would like to thank Matt Tait of Google's Project Zero security
team for reporting the CVE-2015-3214 issue. The CVE-2015-5154 issue was
discovered by Kevin Wolf of Red Hat.

All qemu-kvm-rhev users are advised to upgrade to these updated packages,
which contain a backported patch to correct this issue. After installing
this update, shut down all running virtual machines. Once all virtual
machines have shut down, start them again for this update to take effect.

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

Affected Products

• Red Hat Virtualization 3 for RHEL 7 x86_64

Fixes

• BZ - 1229640 - CVE-2015-3214 qemu/kvm: i8254: out-of-bounds memory access in pit_ioport_read function
• BZ - 1243563 - CVE-2015-5154 qemu: ide: atapi: heap overflow during I/O buffer memory access

CVEs

• CVE-2015-3214
• CVE-2015-5154

References

• https://access.redhat.com/security/updates/classification/#important