Linux Kernel up to 4.13.3 CR8 arch/x86/kvm/vmx.c prepare_vmcs02 access control

CVSS Meta Temp Score
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CTI Interest Score
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6.1$0-$5k0.00

Summaryinfo

A vulnerability has been found in Linux Kernel up to 4.13.3 and classified as critical. This affects the function prepare_vmcs02 of the file arch/x86/kvm/vmx.c of the component CR8 Handler. This manipulation causes access control. This vulnerability is handled as CVE-2017-12154. It is possible to launch the attack on the local host. There is not any exploit available. To fix this issue, it is recommended to deploy a patch.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 4.13.3 (Operating System) and classified as critical. Affected by this vulnerability is the function prepare_vmcs02 of the file arch/x86/kvm/vmx.c of the component CR8 Handler. The manipulation with an unknown input leads to a access control vulnerability. The CWE definition for the vulnerability is CWE-284. The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

The prepare_vmcs02 function in arch/x86/kvm/vmx.c in the Linux kernel through 4.13.3 does not ensure that the "CR8-load exiting" and "CR8-store exiting" L0 vmcs02 controls exist in cases where L1 omits the "use TPR shadow" vmcs12 control, which allows KVM L2 guest OS users to obtain read and write access to the hardware CR8 register.

The bug was discovered 09/15/2017. The weakness was released 09/26/2017 by Matt with Google as confirmed git commit (GIT Repository). It is possible to read the advisory at git.kernel.org. This vulnerability is known as CVE-2017-12154 since 08/01/2017. The exploitation appears to be easy. Attacking locally is a requirement. The exploitation doesn't need any form of authentication. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1068 according to MITRE ATT&CK.

The vulnerability was handled as a non-public zero-day exploit for at least 5 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 103363 (Debian DLA-1099-1 : linux security update (BlueBorne) (Stack Clash)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Debian Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 351447 (Amazon Linux Security Advisory for kernel: ALAC2012-2018-013).

Applying a patch is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. A possible mitigation has been published before and not just after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (103363) and SecurityFocus (BID 100856†). Entries connected to this vulnerability are available at VDB-102802, VDB-103034, VDB-104449 and VDB-104864. Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.2
VulDB Meta Temp Score: 6.1

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.1
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Access control
CWE: CWE-284 / CWE-266
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 103363
Nessus Name: Debian DLA-1099-1 : linux security update (BlueBorne) (Stack Clash)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 53754
OpenVAS Name: Debian Security Advisory DSA 3981-1 (linux - security update)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Patch: git.kernel.org

Timelineinfo

08/01/2017 🔍
09/12/2017 +42 days 🔍
09/15/2017 +3 days 🔍
09/20/2017 +5 days 🔍
09/21/2017 +1 days 🔍
09/26/2017 +5 days 🔍
09/26/2017 +0 days 🔍
09/26/2017 +0 days 🔍
12/30/2022 +1921 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: RHSA-2018:0676
Researcher: Jim Mattson (Matt)
Organization: Google
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2017-12154 (🔍)
GCVE (CVE): GCVE-0-2017-12154
GCVE (VulDB): GCVE-100-107131

OVAL: 🔍

SecurityFocus: 100856 - Linux Kernel CVE-2017-12154 Denial of Service Vulnerability

See also: 🔍

Entryinfo

Created: 09/26/2017 15:12
Updated: 12/30/2022 09:35
Changes: 09/26/2017 15:12 (80), 11/19/2019 16:23 (7), 01/14/2021 13:17 (2), 12/30/2022 09:35 (3)
Complete: 🔍
Cache ID: 216::103

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