Debian DSA-4236-1 : xen - security update

critical Nessus Plugin ID 110787
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Synopsis

The remote Debian host is missing a security-related update.

Description

Multiple vulnerabilities have been discovered in the Xen hypervisor :

- CVE-2018-12891 It was discovered that insufficient validation of PV MMU operations may result in denial of service.

- CVE-2018-12892 It was discovered that libxl fails to honour the 'readonly' flag on HVM-emulated SCSI disks.

- CVE-2018-12893 It was discovered that incorrect implementation of debug exception checks could result in denial of service.

Solution

Upgrade the xen packages.

For the stable distribution (stretch), these problems have been fixed in version 4.8.3+xsa267+shim4.10.1+xsa267-1+deb9u9.

See Also

https://security-tracker.debian.org/tracker/CVE-2018-12891

https://security-tracker.debian.org/tracker/CVE-2018-12892

https://security-tracker.debian.org/tracker/CVE-2018-12893

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

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

https://www.debian.org/security/2018/dsa-4236

Plugin Details

Severity: Critical

ID: 110787

File Name: debian_DSA-4236.nasl

Version: 1.4

Type: local

Agent: unix

Published: 6/29/2018

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: 6.5

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

CVSS v3

Risk Factor: Critical

Base Score: 9.9

Vector: CVSS:3.0/AV:N/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: 6/27/2018

Reference Information

CVE: CVE-2018-12891, CVE-2018-12892, CVE-2018-12893

DSA: 4236