Debian DSA-3554-1 : xen - security update

High Nessus Plugin ID 90638

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VPR Score: 6.5

Synopsis

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

Description

Multiple vulnerabilities have been discovered in the Xen hypervisor.
The Common Vulnerabilities and Exposures project identifies the following problems :

- CVE-2016-3158, CVE-2016-3159 (XSA-172) Jan Beulich from SUSE discovered that Xen does not properly handle writes to the hardware FSW.ES bit when running on AMD64 processors. A malicious domain can take advantage of this flaw to obtain address space usage and timing information, about another domain, at a fairly low rate.

- CVE-2016-3960 (XSA-173) Ling Liu and Yihan Lian of the Cloud Security Team, Qihoo 360 discovered an integer overflow in the x86 shadow pagetable code. A HVM guest using shadow pagetables can cause the host to crash. A PV guest using shadow pagetables (i.e. being migrated) with PV superpages enabled (which is not the default) can crash the host, or corrupt hypervisor memory, potentially leading to privilege escalation.

Solution

Upgrade the xen packages.

For the stable distribution (jessie), these problems have been fixed in version 4.4.1-9+deb8u5.

See Also

https://security-tracker.debian.org/tracker/CVE-2016-3158

https://security-tracker.debian.org/tracker/CVE-2016-3159

https://security-tracker.debian.org/tracker/CVE-2016-3960

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

https://www.debian.org/security/2016/dsa-3554

Plugin Details

Severity: High

ID: 90638

File Name: debian_DSA-3554.nasl

Version: 2.8

Type: local

Agent: unix

Published: 2016/04/22

Updated: 2020/09/23

Dependencies: 12634

Risk Information

Risk Factor: High

VPR Score: 6.5

CVSS v2.0

Base Score: 7.2

Temporal Score: 5.3

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

Temporal Vector: CVSS2#E:U/RL:OF/RC:C

CVSS v3.0

Base Score: 8.8

Temporal Score: 7.7

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

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:debian:debian_linux:xen, cpe:/o:debian:debian_linux:8.0

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

Exploit Available: false

Exploit Ease: No known exploits are available

Patch Publication Date: 2016/04/21

Reference Information

CVE: CVE-2016-3158, CVE-2016-3159, CVE-2016-3960

DSA: 3554