RHSA-2014:0420 - Security Advisory

Topic

Updated qemu-kvm packages that fix multiple security issues 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.

Description

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

Multiple integer overflow, input validation, logic error, and buffer
overflow flaws were discovered in various QEMU block drivers. An attacker
able to modify a disk image file loaded by a guest could use these flaws to
crash the guest, or corrupt QEMU process memory on the host, potentially
resulting in arbitrary code execution on the host with the privileges of
the QEMU process. (CVE-2014-0143, CVE-2014-0144, CVE-2014-0145,
CVE-2014-0147)

A buffer overflow flaw was found in the way the virtio_net_handle_mac()
function of QEMU processed guest requests to update the table of MAC
addresses. A privileged guest user could use this flaw to corrupt QEMU
process memory on the host, potentially resulting in arbitrary code
execution on the host with the privileges of the QEMU process.
(CVE-2014-0150)

A divide-by-zero flaw was found in the seek_to_sector() function of the
parallels block driver in QEMU. An attacker able to modify a disk image
file loaded by a guest could use this flaw to crash the guest.
(CVE-2014-0142)

A NULL pointer dereference flaw was found in the QCOW2 block driver in
QEMU. An attacker able to modify a disk image file loaded by a guest could
use this flaw to crash the guest. (CVE-2014-0146)

It was found that the block driver for Hyper-V VHDX images did not
correctly calculate BAT (Block Allocation Table) entries due to a missing
bounds check. An attacker able to modify a disk image file loaded by a
guest could use this flaw to crash the guest. (CVE-2014-0148)

The CVE-2014-0143 issues were discovered by Kevin Wolf and Stefan Hajnoczi
of Red Hat, the CVE-2014-0144 issues were discovered by Fam Zheng, Jeff
Cody, Kevin Wolf, and Stefan Hajnoczi of Red Hat, the CVE-2014-0145 issues
were discovered by Stefan Hajnoczi of Red Hat, the CVE-2014-0150 issue was
discovered by Michael S. Tsirkin of Red Hat, the CVE-2014-0142,
CVE-2014-0146, and CVE-2014-0147 issues were discovered by Kevin Wolf of
Red Hat, and the CVE-2014-0148 issue was discovered by Jeff Cody of
Red Hat.

All qemu-kvm users are advised to upgrade to these updated packages, which
contain backported patches to correct these issues. 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.

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

Affected Products

• Red Hat Enterprise Linux Server 6 x86_64
• Red Hat Enterprise Linux Server 6 i386
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 6.5 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 6.5 i386
• Red Hat Enterprise Linux Server - AUS 6.5 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 i386
• Red Hat Enterprise Linux Workstation 6 x86_64
• Red Hat Enterprise Linux Workstation 6 i386
• Red Hat Enterprise Linux Desktop 6 x86_64
• Red Hat Enterprise Linux Desktop 6 i386
• Red Hat Enterprise Linux for Scientific Computing 6 x86_64
• Red Hat Enterprise Linux Server from RHUI 6 x86_64
• Red Hat Enterprise Linux Server from RHUI 6 i386
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 6.5 x86_64
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 6.5 i386
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 x86_64
• Red Hat Enterprise Linux EUS Compute Node 6.5 x86_64
• Red Hat Enterprise Linux Server - TUS 6.5 x86_64

Fixes

• BZ - 1078201 - CVE-2014-0142 qemu: crash by possible division by zero
• BZ - 1078212 - CVE-2014-0148 Qemu: vhdx: bounds checking for block_size and logical_sector_size
• BZ - 1078232 - CVE-2014-0146 Qemu: qcow2: NULL dereference in qcow2_open() error path
• BZ - 1078846 - CVE-2014-0150 qemu: virtio-net: buffer overflow in virtio_net_handle_mac() function
• BZ - 1078848 - CVE-2014-0147 Qemu: block: possible crash due signed types or logic error
• BZ - 1078885 - CVE-2014-0145 Qemu: prevent possible buffer overflows
• BZ - 1079140 - CVE-2014-0143 Qemu: block: multiple integer overflow flaws
• BZ - 1079240 - CVE-2014-0144 Qemu: block: missing input validation

CVEs

• CVE-2014-0148
• CVE-2014-0145
• CVE-2014-0144
• CVE-2014-0147
• CVE-2014-0146
• CVE-2014-0143
• CVE-2014-0142
• CVE-2014-0150

References

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