Synopsis

Important: qemu-kvm security update

Type/Severity

Security Advisory: Important

Topic

An update for qemu-kvm is now available for Red Hat Enterprise Linux 6.5 Advanced Update Support.

Red Hat Product Security has rated this update as having a security impact of Important. 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

Kernel-based Virtual Machine (KVM) is a full virtualization solution for Linux on a variety of architectures. The qemu-kvm package provides the user-space component for running virtual machines that use KVM.

Security Fix(es):

• An industry-wide issue was found in the way many modern microprocessor designs have implemented speculative execution of instructions (a commonly used performance optimization). There are three primary variants of the issue which differ in the way the speculative execution can be exploited. Variant CVE-2017-5715 triggers the speculative execution by utilizing branch target injection. It relies on the presence of a precisely-defined instruction sequence in the privileged code as well as the fact that memory accesses may cause allocation into the microprocessor's data cache even for speculatively executed instructions that never actually commit (retire). As a result, an unprivileged attacker could use this flaw to cross the syscall and guest/host boundaries and read privileged memory by conducting targeted cache side-channel attacks. (CVE-2017-5715)
  

Note: This is the qemu-kvm side of the CVE-2017-5715 mitigation.

Red Hat would like to thank Google Project Zero for reporting this issue.

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 Enterprise Linux Server - AUS 6.5 x86_64

Fixes

• BZ - 1519780 - CVE-2017-5715 hw: cpu: speculative execution branch target injection

CVEs

(none)

References

• https://access.redhat.com/security/updates/classification/#important
• https://access.redhat.com/security/vulnerabilities/speculativeexecution
• https://access.redhat.com/security/cve/CVE-2017-5715

Red Hat Enterprise Linux Server - AUS 6.5

SRPM
qemu-kvm-0.12.1.2-2.415.el6_5.17.src.rpm	SHA-256: 857b2d1ffe444a3943a18c7e4906556e981a71f01232e2ea2c3cb653475dfae3
x86_64
qemu-guest-agent-0.12.1.2-2.415.el6_5.17.x86_64.rpm	SHA-256: 948e56bef40cd65d66c4a32e5550e763f4ae019c98c7c15c484ee97cdcff18f4
qemu-img-0.12.1.2-2.415.el6_5.17.x86_64.rpm	SHA-256: ea2c053cb5a837a48b74da16bc9b9bfa2311e31af38db3839b082e320cfe7d64
qemu-kvm-0.12.1.2-2.415.el6_5.17.x86_64.rpm	SHA-256: 7143fc345ccd43562ae290f1cb4d31506ec6fbf643f208024e86b7ccd8abe895
qemu-kvm-debuginfo-0.12.1.2-2.415.el6_5.17.x86_64.rpm	SHA-256: ecb359797ddea1a768e3549d544ea7689e9ce853c78fff74dddcf3ffc08c995a
qemu-kvm-tools-0.12.1.2-2.415.el6_5.17.x86_64.rpm	SHA-256: d4f2667e832046e36f4336a1ec3cb1883adff9c6bc5f764c61560a1c285b3d59