Citrix XenServer QEMU ioport Array Overflow Guest-to-Host Privilege Escalation (CTX219136)

High Nessus Plugin ID 95659


The remote host is affected by a privilege escalation vulnerability.


The version of Citrix XenServer running on the remote host is missing a security hotfix. It is, therefore, affected by a privilege escalation vulnerability in the QEMU ioport component due to an array overflow that is triggered during the handling of addresses in ioport read and write look-ups. A local administrative user on the guest system can exploit this issue to gain elevated privileges on the host system.


Apply the appropriate hotfix according to the vendor advisory.

See Also

Plugin Details

Severity: High

ID: 95659

File Name: citrix_xenserver_CTX219136.nasl

Version: $Revision: 1.5 $

Type: local

Family: Misc.

Published: 2016/12/09

Modified: 2017/02/06

Dependencies: 76770

Risk Information

Risk Factor: High


Base Score: 7.4

Temporal Score: 5.5

Vector: CVSS2#AV:A/AC:M/Au:S/C:C/I:C/A:C

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


Base Score: 7.6

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

Vulnerability Information

CPE: cpe:/a:citrix:xenserver

Required KB Items: Host/XenServer/version, Host/local_checks_enabled

Exploit Available: false

Exploit Ease: No known exploits are available

Patch Publication Date: 2016/12/06

Vulnerability Publication Date: 2016/12/06

Reference Information

CVE: CVE-2016-9637

BID: 93970

OSVDB: 148308