CVE-2016-9386

HIGH

Citrix XenServer - Privilege Escalation via x86 NULL Segment Handling

Title source: llm
STIX 2.1

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.

References (5)

Core 5
Core References
Third Party Advisory, VDB Entry vdb-entry x_refsource_bid
http://www.securityfocus.com/bid/94471
Third Party Advisory vendor-advisory x_refsource_gentoo
https://security.gentoo.org/glsa/201612-56
Patch, Third Party Advisory x_refsource_confirm
https://support.citrix.com/article/CTX218775
Patch, Vendor Advisory x_refsource_confirm
http://xenbits.xen.org/xsa/advisory-191.html
Third Party Advisory, VDB Entry vdb-entry x_refsource_sectrack
http://www.securitytracker.com/id/1037340

Scores

CVSS v3 7.8
EPSS 0.0010
EPSS Percentile 27.2%
Attack Vector LOCAL
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Details

CWE
CWE-264
Status published
Products (5)
citrix/xenserver 6.0.2
citrix/xenserver 6.2.0
citrix/xenserver 6.5
citrix/xenserver 7.0
xen/xen
Published Jan 23, 2017
Tracked Since Feb 18, 2026