Ubuntu 14.04 LTS / 16.04 LTS / 17.10 : libvirt update (USN-3561-1) (Spectre)

medium Nessus Plugin ID 106677
New! Plugin Severity Now Using CVSS v3

The calculated severity for Plugins has been updated to use CVSS v3 by default. Plugins that do not have a CVSS v3 score will fall back to CVSS v2 for calculating severity. Severity display preferences can be toggled in the settings dropdown.

Synopsis

The remote Ubuntu host is missing one or more security-related patches.

Description

It was discovered that microprocessors utilizing speculative execution and branch prediction may allow unauthorized memory reads via sidechannel attacks. This flaw is known as Spectre. An attacker in the guest could use this to expose sensitive guest information, including kernel memory.

This update allows libvirt to expose new CPU features added by microcode updates to guests. On amd64 and i386, new CPU models that match the updated microcode features were added with an -IBRS suffix.
Certain environments will require guests to be switched manually to the new CPU models after microcode updates have been applied to the host.

Note that Tenable Network Security has extracted the preceding description block directly from the Ubuntu security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

Solution

Update the affected libvirt-bin and / or libvirt0 packages.

See Also

https://usn.ubuntu.com/3561-1/

Plugin Details

Severity: Medium

ID: 106677

File Name: ubuntu_USN-3561-1.nasl

Version: 3.10

Type: local

Agent: unix

Published: 2/8/2018

Updated: 4/15/2021

Dependencies: ssh_get_info.nasl

Risk Information

VPR

Risk Factor: High

Score: 7.6

CVSS v2

Risk Factor: Low

Base Score: 1.9

Temporal Score: 1.7

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

Temporal Vector: E:H/RL:OF/RC:C

CVSS v3

Risk Factor: Medium

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: E:H/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:canonical:ubuntu_linux:libvirt-bin, p-cpe:/a:canonical:ubuntu_linux:libvirt0, cpe:/o:canonical:ubuntu_linux:14.04, cpe:/o:canonical:ubuntu_linux:16.04, cpe:/o:canonical:ubuntu_linux:17.10

Required KB Items: Host/cpu, Host/Ubuntu, Host/Ubuntu/release, Host/Debian/dpkg-l

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 2/7/2018

Vulnerability Publication Date: 1/4/2018

Reference Information

CVE: CVE-2017-5715

USN: 3561-1

IAVA: 2018-A-0020