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TI-2016-07843 Aliases CVE-2016-9637GHSA-5m8h-4qv2-6hhp

The (1) ioport_read and (2) ioport_write functions in Xen, when qemu is used as a device…

Priority LOW 33CWE-264Published · Updated

Key facts

Attack vector
Local
Privileges required
High
User interaction
None
Attack complexity
High
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.0 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-264.

Summary

The (1) ioport_read and (2) ioport_write functions in Xen, when qemu is used as a device model within Xen, might allow local x86 HVM guest OS administrators to gain qemu process privileges via vectors involving an out-of-range ioport access.

Why it matters now

EPSS 0.00364 30th percentileScored 2026-11-07
Fix Fixed Red Hat: 1 advisory

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 4

CPEVersionsRoleVendor
cpe:2.3:a:citrix:xenserver:6.0.2:*:*:*:*:*:*:*6.0.2VulnerableCitrix
cpe:2.3:a:citrix:xenserver:6.2.0:sp1:*:*:*:*:*:*6.2.0 sp1VulnerableCitrix
cpe:2.3:a:citrix:xenserver:6.5:sp1:*:*:*:*:*:*6.5 sp1VulnerableCitrix
cpe:2.3:a:citrix:xenserver:7.0:*:*:*:*:*:*:*7.0VulnerableCitrix
  • cpe:2.3:a:citrix:xenserver:6.0.2:*:*:*:*:*:*:* Versions 6.0.2 Vulnerable ·Citrix
  • cpe:2.3:a:citrix:xenserver:6.2.0:sp1:*:*:*:*:*:* Versions 6.2.0 sp1 Vulnerable ·Citrix
  • cpe:2.3:a:citrix:xenserver:6.5:sp1:*:*:*:*:*:* Versions 6.5 sp1 Vulnerable ·Citrix
  • cpe:2.3:a:citrix:xenserver:7.0:*:*:*:*:*:*:* Versions 7.0 Vulnerable ·Citrix

Remediation

Red Hat 1 advisory

  • RHSA-2016:2963 Released 2016-12-20 · Red Hat rating Important
    xen security update
    • Red Hat Enterprise Linux (v. 5 server) xen-3.0.3-148.el5_11, xen-libs-3.0.3-148.el5_11, xen-libs-3.0.3-148.el5_11.i386 +1
    • Red Hat Enterprise Linux Desktop (v. 5 client) xen-3.0.3-148.el5_11, xen-libs-3.0.3-148.el5_11, xen-libs-3.0.3-148.el5_11.i386
    • Red Hat Enterprise Linux Desktop Multi OS (v. 5 client) xen-3.0.3-148.el5_11, xen-3.0.3-148.el5_11.i386, xen-devel-3.0.3-148.el5_11 +1
    • Red Hat Enterprise Linux Virtualization (v. 5 server) xen-3.0.3-148.el5_11, xen-3.0.3-148.el5_11.i386, xen-3.0.3-148.el5_11.ia64 +3

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux (v. 5 server)Fixed RHSA-2016:2963
Red Hat Enterprise Linux Desktop (v. 5 client)Fixed RHSA-2016:2963
Red Hat Enterprise Linux Desktop Multi OS (v. 5 client)Fixed RHSA-2016:2963
Red Hat Enterprise Linux Virtualization (v. 5 server)Fixed RHSA-2016:2963
Not affected: 8 products
  • Red Hat Enterprise Linux 5
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux OpenStack Platform 5 (Icehouse)
  • Red Hat Enterprise Linux OpenStack Platform 6 (Juno)
  • Red Hat Enterprise Linux OpenStack Platform 7 (Kilo)
  • Red Hat OpenStack Platform 8 (Liberty)
  • Red Hat OpenStack Platform 9 (Mitaka)

Timeline

  1. 2026-10-02 Threatist record created from CVE-2016-9637
  2. 2026-10-03 Alias added: GHSA-5m8h-4qv2-6hhp

References

Advisory 2

Other 3

  • TI-2018-10124 Citrix XenServer 7.1 and newer allows Directory Traversal. CVSS 3.0CRITICAL 9.8
  • TI-2012-00210 The x86-64 kernel system-call functionality in Xen 4.1.2 and earlier, as used in Citrix… CVSS 2.0HIGH 7.2
  • TI-2015-06402 The rate limiting feature in NTP 4.x before 4.2.8p4 and 4.3.x before 4.3.77 allows remote… CVSS 3.1CRITICAL 9.8
  • TI-2018-06436 A statement in the System Programming Guide of the Intel 64 and IA-32 Architectures… CVSS 3.0HIGH 7.8
  • TI-2014-04065 Buffer overflow in the HVM graphics console support in Citrix XenServer 6.2 Service Pack… CVSS 2.0HIGH 10.0
  • TI-2016-07824 Heap-based buffer overflow in Qemu: CVSS 3.0CRITICAL 9.9
See all 49 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences