CVE-2016-9386

Publication date 23 January 2017

Last updated 25 August 2025

Ubuntu priority

Cvss 3 Severity Score

Description

The x86 emulator in Xen does not properly treat x86 NULL segments as unusable when accessing memory, which might allow local HVM guest users to gain privileges via vectors involving "unexpected" base/limit values.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
xen	17.04 zesty	Fixed 4.8.0-1ubuntu1
	16.10 yakkety	Fixed 4.7.0-0ubuntu2.1
	16.04 LTS xenial	Fixed 4.6.0-1ubuntu4.3
	14.04 LTS trusty	Fixed 4.4.2-0ubuntu0.14.04.9
	12.04 LTS precise	Fixed 4.1.6.1-0ubuntu0.12.04.13

Notes

mdeslaur

This is XSA-191

Severity score breakdown

CVSS version: CVSS v3.0

Base score 7.8 · High

Base metrics

Parameter	Value
Attack vector	Local
Attack complexity	Low
Privileges required	Low
User interaction	None
Scope	Unchanged
Confidentiality impact	High
Integrity impact	High
Availability impact	High

Scores

Parameter	Value
Base score	7.8 · High
Exploitability score	-
Impact score	-

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