CVE-2016-4020

  1. OpenCVE
  2. Vulnerabilities (CVE)
  3. CVE-2016-4020
The patch_instruction function in hw/i386/kvmvapic.c in QEMU does not initialize the imm32 variable, which allows local guest OS administrators to obtain sensitive information from host stack memory by accessing the Task Priority Register (TPR).

6.5 /10

CVSS v3 : MEDIUM

V3 Legend

Vector :

Exploitability : 2.0 / Impact : 4.0

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope CHANGED

2.1 /10

CVSS v2.0 : LOW

V2 Legend

Vector : AV:L/AC:L/Au:N/C:P/I:N/A:N

Exploitability : 3.9 / Impact : 2.9

Access Vector LOCAL

Access Complexity LOW

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact NONE

Availability Impact NONE

References
Link Resource
http://git.qemu.org/?p=qemu.git%3Ba=commit%3Bh=691a02e2ce0c413236a78dee6f2651c937b09fb0
http://www.securityfocus.com/bid/86067 Third Party Advisory VDB Entry
http://www.ubuntu.com/usn/USN-2974-1 Third Party Advisory
https://access.redhat.com/errata/RHSA-2017:1856 Third Party Advisory
https://access.redhat.com/errata/RHSA-2017:2392 Third Party Advisory
https://access.redhat.com/errata/RHSA-2017:2408 Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1313686 Issue Tracking Third Party Advisory
https://lists.debian.org/debian-lts-announce/2018/11/msg00038.html Mailing List Third Party Advisory
https://lists.gnu.org/archive/html/qemu-devel/2016-04/msg01106.html Patch Third Party Advisory
https://lists.gnu.org/archive/html/qemu-devel/2016-04/msg01118.html Patch Third Party Advisory
https://security.gentoo.org/glsa/201609-01 Third Party Advisory
Configurations

Configuration 1 (hide)

cpe:2.3:a:qemu:qemu:*:*:*:*:*:*:*:*

Configuration 2 (hide)

OR cpe:2.3:o:canonical:ubuntu_linux:12.04:*:*:*:esm:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:esm:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:15.10:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*

Configuration 3 (hide)

cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*

Configuration 4 (hide)

OR cpe:2.3:a:redhat:openstack:6.0:*:*:*:*:*:*:*
cpe:2.3:a:redhat:openstack:7.0:*:*:*:*:*:*:*
cpe:2.3:a:redhat:openstack:8:*:*:*:*:*:*:*
cpe:2.3:a:redhat:openstack:9:*:*:*:*:*:*:*
cpe:2.3:a:redhat:openstack:10:*:*:*:*:*:*:*
cpe:2.3:a:redhat:openstack:11:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_desktop:7.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_eus:7.4:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_eus:7.5:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_eus:7.6:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_eus:7.7:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server:7.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server_aus:7.4:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server_aus:7.6:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server_aus:7.7:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server_tus:7.6:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server_tus:7.7:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_workstation:7.0:*:*:*:*:*:*:*

Configuration 5 (hide)

AND
cpe:2.3:a:redhat:virtualization:4.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*
History

13 Feb 2023, 04:50

Type Values Removed Values Added
References
  • {'url': 'https://access.redhat.com/security/cve/CVE-2016-4020', 'name': 'https://access.redhat.com/security/cve/CVE-2016-4020', 'tags': [], 'refsource': 'MISC'}
Summary An information-exposure flaw was found in Quick Emulator (QEMU) in Task Priority Register (TPR) optimizations for 32-bit Windows guests. The flaw could occur while accessing TPR. A privileged user inside a guest could use this issue to read portions of the host memory. The patch_instruction function in hw/i386/kvmvapic.c in QEMU does not initialize the imm32 variable, which allows local guest OS administrators to obtain sensitive information from host stack memory by accessing the Task Priority Register (TPR).

02 Feb 2023, 16:17

Type Values Removed Values Added
References
  • {'url': 'http://git.qemu.org/?p=qemu.git;a=commit;h=691a02e2ce0c413236a78dee6f2651c937b09fb0', 'name': 'http://git.qemu.org/?p=qemu.git;a=commit;h=691a02e2ce0c413236a78dee6f2651c937b09fb0', 'tags': ['Patch', 'Vendor Advisory'], 'refsource': 'CONFIRM'}
  • (MISC) https://access.redhat.com/security/cve/CVE-2016-4020 -
  • (MISC) http://git.qemu.org/?p=qemu.git%3Ba=commit%3Bh=691a02e2ce0c413236a78dee6f2651c937b09fb0 -
Summary The patch_instruction function in hw/i386/kvmvapic.c in QEMU does not initialize the imm32 variable, which allows local guest OS administrators to obtain sensitive information from host stack memory by accessing the Task Priority Register (TPR). An information-exposure flaw was found in Quick Emulator (QEMU) in Task Priority Register (TPR) optimizations for 32-bit Windows guests. The flaw could occur while accessing TPR. A privileged user inside a guest could use this issue to read portions of the host memory.

04 Aug 2021, 17:15

Type Values Removed Values Added
CPE cpe:2.3:a:redhat:openstack:9.0:*:*:*:*:*:*:*
cpe:2.3:a:redhat:openstack:8.0:*:*:*:*:*:*:*
cpe:2.3:a:redhat:openstack:11.0:*:*:*:*:*:*:*		 cpe:2.3:a:redhat:openstack:11:*:*:*:*:*:*:*
cpe:2.3:a:redhat:openstack:9:*:*:*:*:*:*:*
cpe:2.3:a:redhat:openstack:8:*:*:*:*:*:*:*
Information

Published : 2016-05-25 15:59

Updated : 2023-12-10 11:46

NVD link : CVE-2016-4020

Mitre link : CVE-2016-4020

CVE.ORG link : CVE-2016-4020

JSON object : View

Products Affected

debian

  • debian_linux

redhat

  • enterprise_linux_server_aus
  • enterprise_linux
  • openstack
  • enterprise_linux_server_tus
  • enterprise_linux_server
  • enterprise_linux_workstation
  • virtualization
  • enterprise_linux_desktop
  • enterprise_linux_eus

qemu

  • qemu

canonical

  • ubuntu_linux
CWE
NVD-CWE-noinfo