RHSA-2018:2364 - Security Advisory

Topic

An update for qemu-kvm-rhev is now available for Red Hat OpenStack Platform
8.

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

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):

• 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)

Acknowledgements:

Red Hat would like to thank Ken Johnson (Microsoft Security Response Center)
and Jann Horn (Google Project Zero) for reporting this issue.

Note: This is the qemu-kvm-rhev side of the CVE-2018-3639 mitigation that
includes support for guests running on hosts with AMD processors.

For more details about the security issue(s), including the impact, a CVSS
score, and other related information, refer to the CVE page(s) listed in
the References section.

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

Affected Products

• Red Hat OpenStack 8 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