Topic

An update for qemu-kvm-rhev is now available for Red Hat Enterprise Virtualization (RHEV) 4.X, Red Hat Enterprise Virtualization Hypervisor (RHEV-H) and Agents for Red Hat Enterprise Linux 7.

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

Description

KVM (Kernel-based Virtual Machine) is a full virtualization solution for Linux on a variety of architectures. The qemu-kvm-rhev packages provide the user-space component for running virtual machines that use KVM in environments managed by Red Hat products.

Security Fix(es):

• Quick Emulator (QEMU), compiled with qemu_map_ram_ptr to access guests' RAM block area, is vulnerable to an OOB r/w access issue. The crash can occur if a privileged user inside a guest conducts certain DMA operations, resulting in a DoS. (CVE-2017-11334)
• Quick Emulator (QEMU), compiled with the PC System Emulator with multiboot feature support, is vulnerable to an OOB r/w memory access issue. The issue could occur due to an integer overflow while loading a kernel image during a guest boot. A user or process could use this flaw to potentially achieve arbitrary code execution on a host. (CVE-2017-14167)
• Quick emulator (QEMU), compiled with the Cirrus CLGD 54xx VGA Emulator support, is vulnerable to an OOB write access issue. The issue could occur while writing to VGA memory via mode4and5 write functions. A privileged user inside guest could use this flaw to crash the QEMU process resulting in Denial of Serivce (DoS). (CVE-2017-15289)

Red Hat would like to thank Alex for reporting CVE-2017-11334; Thomas Garnier (Google.com) for reporting CVE-2017-14167; and Guoxiang Niu (Huawei.com) for reporting CVE-2017-15289.

Bug Fix(es):

• Improvements made for qemu 2.9 to the NBD code used during live storage migration were not robust to an abrupt exit of the other end of the connection; the result was that live migration could fail if the source side NBD connection failed. The NBD code has been fixed to be more robust regardless of what the other side of the connection does. (BZ#1495474)

Solution

For details on how to apply this update, which includes the changes described in this advisory, refer to:

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

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.

Affected Products

• Red Hat Virtualization 4 for RHEL 7 x86_64
• Red Hat Virtualization for IBM Power LE 4 for RHEL 7 ppc64le

Fixes

• BZ - 1471638 - CVE-2017-11334 Qemu: exec: oob access during dma operation
• BZ - 1489375 - CVE-2017-14167 Qemu: i386: multiboot OOB access while loading kernel image
• BZ - 1495474 - Fail to quit source qemu when do live migration after mirroring guest to NBD server [rhel-7.4.z]
• BZ - 1501290 - CVE-2017-15289 Qemu: cirrus: OOB access issue in mode4and5 write functions

CVEs

• CVE-2017-11334
• CVE-2017-14167
• CVE-2017-15289

References

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