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 6.4 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 packages provide 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 Load & Store instructions (a commonly used performance optimization). It relies on the presence of a precisely-defined instruction sequence in the privileged code as well as the fact that memory read from address to which a recent memory write has occurred may see an older value and subsequently cause an update 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 read privileged memory by conducting targeted cache side-channel attacks. (CVE-2018-3639)
  

Note: This is the qemu-kvm side of the CVE-2018-3639 mitigation.

Red Hat would like to thank Ken Johnson (Microsoft Security Response Center) and Jann Horn (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 6.4 x86_64

Fixes

• BZ - 1566890 - CVE-2018-3639 hw: cpu: speculative store bypass

CVEs

• CVE-2018-3639

References

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

Red Hat Enterprise Linux Server - AUS 6.4

SRPM
qemu-kvm-0.12.1.2-2.355.el6_4.11.src.rpm	SHA-256: efd9a5a4beaaab099c1e42bf8e4d8bb78f106a19dc730ae2d702181ed0f98322
x86_64
qemu-guest-agent-0.12.1.2-2.355.el6_4.11.x86_64.rpm	SHA-256: da46b2ec75c512bc45eedbda29e6c0baec96acc34417e36432dfd5f92b2030f9
qemu-guest-agent-win32-0.12.1.2-2.355.el6_4.11.x86_64.rpm	SHA-256: 3e713fd47813d7c70b42989823931f28ce61adeb37aae7919c95d26ad27f2076
qemu-img-0.12.1.2-2.355.el6_4.11.x86_64.rpm	SHA-256: 215b61500c3f08281366b7c007e119f3d1b31d2552b39303f823e99355c56319
qemu-kvm-0.12.1.2-2.355.el6_4.11.x86_64.rpm	SHA-256: 9dbdb33fd39feb1baf383b20fdee13156444bb600ae60dd0cfde9a4f0f7ea310
qemu-kvm-debuginfo-0.12.1.2-2.355.el6_4.11.x86_64.rpm	SHA-256: db58991e1b86333ead0f0e5aab76a1d08debdb440cc996deea053aa4da631dc5
qemu-kvm-debuginfo-0.12.1.2-2.355.el6_4.11.x86_64.rpm	SHA-256: db58991e1b86333ead0f0e5aab76a1d08debdb440cc996deea053aa4da631dc5
qemu-kvm-tools-0.12.1.2-2.355.el6_4.11.x86_64.rpm	SHA-256: dab7accd0b37b5e12f187b5cc67fa2bb13733391891cdc1b3b90be51afcdacd1