CVE-2016-6259

Publication date 2 August 2016

Last updated 25 August 2025

Ubuntu priority

Cvss 3 Severity Score

Description

Xen 4.5.x through 4.7.x do not implement Supervisor Mode Access Prevention (SMAP) whitelisting in 32-bit exception and event delivery, which allows local 32-bit PV guest OS kernels to cause a denial of service (hypervisor and VM crash) by triggering a safety check.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
xen	16.04 LTS xenial	Fixed 4.6.0-1ubuntu4.2
	15.10 wily	Ignored end of life
	14.04 LTS trusty	Not in release
	12.04 LTS precise	Not affected

Notes

mdeslaur

4.5+ only

Severity score breakdown

CVSS version: CVSS v3.0

Base score 6.2 · Medium

Base metrics

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

Scores

Parameter	Value
Base score	6.2 · Medium
Exploitability score	-
Impact score	-

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