RHEL 7 : libvirt (RHSA-2018:1997) (Spectre)

Medium Nessus Plugin ID 110711

Synopsis

The remote Red Hat host is missing one or more security updates.

Description

An update for libvirt 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.

The libvirt library contains a C API for managing and interacting with the virtualization capabilities of Linux and other operating systems.
In addition, libvirt provides tools for remote management of virtualized systems.

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 libvirt side of the CVE-2018-3639 mitigation that includes support for guests running on hosts with AMD processors.

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

Bug Fix(es) :

* Previously, the virtlogd service logged redundant AVC denial errors when a guest virtual machine was started. With this update, the virtlogd service no longer attempts to send shutdown inhibition calls to systemd, which prevents the described errors from occurring.
(BZ#1573268)

* Prior to this update, guest virtual machine actions that use a python library in some cases failed and 'Hash operation not allowed during iteration' error messages were logged. Several redundant thread access checks have been removed, and the problem no longer occurs.
(BZ#1581364)

* The 'virsh capabilities' command previously displayed an inaccurate number of 4 KiB memory pages on systems with very large amounts of memory. This update optimizes the memory diagnostic mechanism to ensure memory page numbers are displayed correctly on such systems.
(BZ#1582418)

Solution

Update the affected packages.

See Also

http://rhn.redhat.com/errata/RHSA-2018-1997.html

https://www.redhat.com/security/data/cve/CVE-2018-3639.html

Plugin Details

Severity: Medium

ID: 110711

File Name: redhat-RHSA-2018-1997.nasl

Version: 1.3

Type: local

Agent: unix

Published: 2018/06/27

Modified: 2018/09/07

Dependencies: 12634

Risk Information

Risk Factor: Medium

CVSSv2

Base Score: 4.9

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

CVSSv3

Base Score: 5.5

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

Vulnerability Information

CPE: p-cpe:/a:redhat:enterprise_linux:libvirt, p-cpe:/a:redhat:enterprise_linux:libvirt-admin, p-cpe:/a:redhat:enterprise_linux:libvirt-client, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-config-network, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-config-nwfilter, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-driver-interface, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-driver-lxc, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-driver-network, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-driver-nodedev, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-driver-nwfilter, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-driver-qemu, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-driver-secret, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-driver-storage, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-driver-storage-core, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-driver-storage-disk, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-driver-storage-gluster, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-driver-storage-iscsi, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-driver-storage-logical, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-driver-storage-mpath, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-driver-storage-rbd, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-driver-storage-scsi, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-kvm, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-lxc, p-cpe:/a:redhat:enterprise_linux:libvirt-debuginfo, p-cpe:/a:redhat:enterprise_linux:libvirt-devel, p-cpe:/a:redhat:enterprise_linux:libvirt-docs, p-cpe:/a:redhat:enterprise_linux:libvirt-libs, p-cpe:/a:redhat:enterprise_linux:libvirt-lock-sanlock, p-cpe:/a:redhat:enterprise_linux:libvirt-login-shell, p-cpe:/a:redhat:enterprise_linux:libvirt-nss, cpe:/o:redhat:enterprise_linux:7, cpe:/o:redhat:enterprise_linux:7.5

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

Patch Publication Date: 2018/06/26

Reference Information

CVE: CVE-2018-3639

RHSA: 2018:1997