CentOS 7 : qemu-kvm (CESA-2018:0023) (Spectre)

Medium Nessus Plugin ID 105592


The remote CentOS host is missing one or more security updates.


An update for qemu-kvm is now available for Red Hat Enterprise Linux 7.

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.

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.


Update the affected qemu-kvm packages.

See Also


Plugin Details

Severity: Medium

ID: 105592

File Name: centos_RHSA-2018-0023.nasl

Version: $Revision: 3.7 $

Type: local

Agent: unix

Published: 2018/01/05

Modified: 2018/01/29

Dependencies: 12634

Risk Information

Risk Factor: Medium


Base Score: 4.7

Temporal Score: 4.5

Vector: CVSS2#AV:L/AC:M/Au:N/C:C/I:N/A:N

Temporal Vector: CVSS2#E:F/RL:ND/RC:ND


Base Score: 5.6

Temporal Score: 5.4

Vector: CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N

Temporal Vector: CVSS:3.0/E:F/RL:X/RC:X

Vulnerability Information

CPE: p-cpe:/a:centos:centos:qemu-img, p-cpe:/a:centos:centos:qemu-kvm, p-cpe:/a:centos:centos:qemu-kvm-common, p-cpe:/a:centos:centos:qemu-kvm-tools, cpe:/o:centos:centos:7

Required KB Items: Host/local_checks_enabled, Host/CentOS/release, Host/CentOS/rpm-list

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 2018/01/04

Reference Information

CVE: CVE-2017-5715

OSVDB: 171897

RHSA: 2018:0023

IAVA: 2018-A-0020