Debian DSA-4131-1 : xen - security update

high Nessus Plugin ID 107123
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 Debian host is missing a security-related update.

Description

Multiple vulnerabilities have been discovered in the Xen hypervisor :

- CVE-2018-7540 Jann Horn discovered that missing checks in page table freeing may result in denial of service.

- CVE-2018-7541 Jan Beulich discovered that incorrect error handling in grant table checks may result in guest-to-host denial of service and potentially privilege escalation.

- CVE-2018-7542 Ian Jackson discovered that insufficient handling of x86 PVH guests without local APICs may result in guest-to-host denial of service.

Solution

Upgrade the xen packages.

For the stable distribution (stretch), these problems have been fixed in version 4.8.3+comet2+shim4.10.0+comet3-1+deb9u5.

See Also

https://security-tracker.debian.org/tracker/CVE-2018-7540

https://security-tracker.debian.org/tracker/CVE-2018-7541

https://security-tracker.debian.org/tracker/CVE-2018-7542

https://security-tracker.debian.org/tracker/source-package/xen

https://packages.debian.org/source/stretch/xen

https://www.debian.org/security/2018/dsa-4131

Plugin Details

Severity: High

ID: 107123

File Name: debian_DSA-4131.nasl

Version: 3.4

Type: local

Agent: unix

Published: 3/5/2018

Updated: 11/13/2018

Dependencies: ssh_get_info.nasl

Risk Information

VPR

Risk Factor: Medium

Score: 6.5

CVSS v2

Risk Factor: Medium

Base Score: 6.1

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

CVSS v3

Risk Factor: High

Base Score: 8.8

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

Vulnerability Information

CPE: p-cpe:/a:debian:debian_linux:xen, cpe:/o:debian:debian_linux:9.0

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

Patch Publication Date: 3/4/2018

Reference Information

CVE: CVE-2018-7540, CVE-2018-7541, CVE-2018-7542

DSA: 4131