6.5
MEDIUM
CVE-2016-4020
QEMU KVMvapic Information Disclosure Vulnerability
Description
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).
INFO
Published Date :
May 25, 2016, 3:59 p.m.
Last Modified :
Feb. 13, 2023, 4:50 a.m.
Source :
[email protected]
Remotely Exploitable :
No
Impact Score :
4.0
Exploitability Score :
2.0
Affected Products
The following products are affected by CVE-2016-4020
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2016-4020.
| URL | 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 |
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2016-4020 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2016-4020 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by [email protected]
May. 14, 2024
Action Type Old Value New Value -
CVE Modified by [email protected]
Feb. 13, 2023
Action Type Old Value New Value Changed Description 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). Removed CVSS V2 Red Hat, Inc. (AV:A/AC:M/Au:N/C:P/I:N/A:N) Removed CVSS V3 Red Hat, Inc. AV:A/AC:H/PR:N/UI:N/S:C/C:L/I:N/A:N Removed Reference https://access.redhat.com/security/cve/CVE-2016-4020 [No Types Assigned] -
CVE Modified by [email protected]
Feb. 02, 2023
Action Type Old Value New Value Changed Description 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. Added CVSS V2 Red Hat, Inc. (AV:A/AC:M/Au:N/C:P/I:N/A:N) Added CVSS V3 Red Hat, Inc. AV:A/AC:H/PR:N/UI:N/S:C/C:L/I:N/A:N Removed Reference http://git.qemu.org/?p=qemu.git;a=commit;h=691a02e2ce0c413236a78dee6f2651c937b09fb0 [Patch, Vendor Advisory] Added Reference http://git.qemu.org/?p=qemu.git%3Ba=commit%3Bh=691a02e2ce0c413236a78dee6f2651c937b09fb0 [No Types Assigned] Added Reference https://access.redhat.com/security/cve/CVE-2016-4020 [No Types Assigned] -
CPE Deprecation Remap by [email protected]
Aug. 04, 2021
Action Type Old Value New Value Changed CPE Configuration OR *cpe:2.3:a:redhat:openstack:9.0:*:*:*:*:*:*:* OR *cpe:2.3:a:redhat:openstack:9:*:*:*:*:*:*:* -
CPE Deprecation Remap by [email protected]
Aug. 04, 2021
Action Type Old Value New Value Changed CPE Configuration OR *cpe:2.3:a:redhat:openstack:11.0:*:*:*:*:*:*:* OR *cpe:2.3:a:redhat:openstack:11:*:*:*:*:*:*:* -
CPE Deprecation Remap by [email protected]
Aug. 04, 2021
Action Type Old Value New Value Changed CPE Configuration OR *cpe:2.3:a:redhat:openstack:8.0:*:*:*:*:*:*:* OR *cpe:2.3:a:redhat:openstack:8:*:*:*:*:*:*:* -
Modified Analysis by [email protected]
Oct. 15, 2020
Action Type Old Value New Value Removed CVSS V3 NIST AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N Added CVSS V3.1 NIST AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N Changed Reference Type http://git.qemu.org/?p=qemu.git;a=commit;h=691a02e2ce0c413236a78dee6f2651c937b09fb0 Vendor Advisory http://git.qemu.org/?p=qemu.git;a=commit;h=691a02e2ce0c413236a78dee6f2651c937b09fb0 Patch, Vendor Advisory Changed Reference Type http://www.securityfocus.com/bid/86067 No Types Assigned http://www.securityfocus.com/bid/86067 Third Party Advisory, VDB Entry Changed Reference Type http://www.ubuntu.com/usn/USN-2974-1 No Types Assigned http://www.ubuntu.com/usn/USN-2974-1 Third Party Advisory Changed Reference Type https://access.redhat.com/errata/RHSA-2017:1856 No Types Assigned https://access.redhat.com/errata/RHSA-2017:1856 Third Party Advisory Changed Reference Type https://access.redhat.com/errata/RHSA-2017:2392 No Types Assigned https://access.redhat.com/errata/RHSA-2017:2392 Third Party Advisory Changed Reference Type https://access.redhat.com/errata/RHSA-2017:2408 No Types Assigned https://access.redhat.com/errata/RHSA-2017:2408 Third Party Advisory Changed Reference Type https://bugzilla.redhat.com/show_bug.cgi?id=1313686 No Types Assigned https://bugzilla.redhat.com/show_bug.cgi?id=1313686 Issue Tracking, Third Party Advisory Changed Reference Type https://lists.debian.org/debian-lts-announce/2018/11/msg00038.html No Types Assigned https://lists.debian.org/debian-lts-announce/2018/11/msg00038.html Mailing List, Third Party Advisory Changed Reference Type https://lists.gnu.org/archive/html/qemu-devel/2016-04/msg01106.html Vendor Advisory https://lists.gnu.org/archive/html/qemu-devel/2016-04/msg01106.html Patch, Third Party Advisory Changed Reference Type https://lists.gnu.org/archive/html/qemu-devel/2016-04/msg01118.html No Types Assigned https://lists.gnu.org/archive/html/qemu-devel/2016-04/msg01118.html Patch, Third Party Advisory Changed Reference Type https://security.gentoo.org/glsa/201609-01 No Types Assigned https://security.gentoo.org/glsa/201609-01 Third Party Advisory Removed CWE NIST CWE-200 Added CWE NIST NVD-CWE-noinfo Changed CPE Configuration OR *cpe:2.3:a:qemu:qemu:-:*:*:*:*:*:*:* OR *cpe:2.3:a:qemu:qemu:*:*:*:*:*:*:*:* versions up to (including) 2.6.2 Changed CPE Configuration OR *cpe:2.3:o:canonical:ubuntu_linux:12.04:*:*:*:lts:*:*:* *cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:* *cpe:2.3:o:canonical:ubuntu_linux:15.10:*:*:*:*:*:*:* *cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:* 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:*:*:* Added CPE Configuration OR *cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:* Added CPE Configuration OR *cpe:2.3:a:redhat:openstack:6.0:*:*:*:*:*:*:* *cpe:2.3:a:redhat:openstack:7.0:*:*:*:*:*:*:* *cpe:2.3:a:redhat:openstack:8.0:*:*:*:*:*:*:* *cpe:2.3:a:redhat:openstack:9.0:*:*:*:*:*:*:* *cpe:2.3:a:redhat:openstack:10:*:*:*:*:*:*:* *cpe:2.3:a:redhat:openstack:11.0:*:*:*:*:*:*:* *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:*:*:*:*:*:*:* Added CPE Configuration AND OR *cpe:2.3:a:redhat:virtualization:4.0:*:*:*:*:*:*:* OR cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:* -
CVE Modified by [email protected]
Dec. 01, 2018
Action Type Old Value New Value Added Reference https://lists.debian.org/debian-lts-announce/2018/11/msg00038.html [No Types Assigned] -
CVE Modified by [email protected]
Jan. 05, 2018
Action Type Old Value New Value Added Reference https://access.redhat.com/errata/RHSA-2017:2408 [No Types Assigned] Added Reference https://access.redhat.com/errata/RHSA-2017:2392 [No Types Assigned] Added Reference https://access.redhat.com/errata/RHSA-2017:1856 [No Types Assigned] -
CVE Modified by [email protected]
Jul. 01, 2017
Action Type Old Value New Value Added Reference https://security.gentoo.org/glsa/201609-01 [No Types Assigned] -
CVE Modified by [email protected]
Nov. 28, 2016
Action Type Old Value New Value Added Reference http://www.securityfocus.com/bid/86067 [No Types Assigned] -
Modified Analysis by [email protected]
Jun. 21, 2016
Action Type Old Value New Value Changed CPE Configuration Configuration 1 OR *cpe:2.3:a:qemu:qemu:-:*:*:*:*:*:*:* Configuration 1 OR *cpe:2.3:a:qemu:qemu:-:*:*:*:*:*:*:* Configuration 2 OR *cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:* *cpe:2.3:o:canonical:ubuntu_linux:15.10:*:*:*:*:*:*:* *cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:* *cpe:2.3:o:canonical:ubuntu_linux:12.04:*:*:*:lts:*:*:* -
CVE Modified by [email protected]
Jun. 21, 2016
Action Type Old Value New Value Added Reference http://www.ubuntu.com/usn/USN-2974-1 -
CVE Translated by [email protected]
May. 29, 2016
Action Type Old Value New Value Removed Translation La función patch_instruction en hw/i386/kvmvapic.c en QEMU no inicializa la variable imm32, lo que permite a administradores locales del SO invitado obtener información sensible de la memoria de pila del anfitrión accediendo a Task Priorty Register (TPR). Added Translation La función patch_instruction en hw/i386/kvmvapic.c en QEMU no inicializa la variable imm32, lo que permite a administradores locales del SO invitado obtener información sensible de la memoria de pila del anfitrión accediendo al Task Priority Register (TPR). -
CVE Modified by [email protected]
May. 29, 2016
Action Type Old Value New Value Changed Description 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 Priorty Register (TPR). 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). -
Modified Analysis by [email protected]
May. 25, 2016
Action Type Old Value New Value Added CPE Configuration Configuration 1 OR *cpe:2.3:a:qemu:qemu:-:*:*:*:*:*:*:* Added CVSS V2 (AV:L/AC:L/Au:N/C:P/I:N/A:N) Added CVSS V3 AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N Changed Reference Type http://git.qemu.org/?p=qemu.git;a=commit;h=691a02e2ce0c413236a78dee6f2651c937b09fb0 No Types Assigned http://git.qemu.org/?p=qemu.git;a=commit;h=691a02e2ce0c413236a78dee6f2651c937b09fb0 Advisory Changed Reference Type https://lists.gnu.org/archive/html/qemu-devel/2016-04/msg01106.html No Types Assigned https://lists.gnu.org/archive/html/qemu-devel/2016-04/msg01106.html Advisory Added CWE CWE-200 -
Initial Analysis by [email protected]
May. 25, 2016
Action Type Old Value New Value
EPSS is a daily estimate of the probability of exploitation activity
being observed over the next 30 days. Following chart shows the EPSS
score history of the vulnerability.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2016-4020 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2016-4020
weaknesses.
Exploit Prediction
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.
0.06 }} 0.00%
score
0.23061
percentile
CVSS31 - Vulnerability Scoring System
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability