Microsoft Windows up to Server 2016 Win32k information disclosure

CVSS Meta Temp Score
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CTI Interest Score
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6.2$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, has been found in Microsoft Windows up to Server 2016. This issue affects some unknown processing in the library Win32k. This manipulation causes information disclosure. This vulnerability appears as CVE-2017-8666. The attack requires local access. There is no available exploit. To fix this issue, it is recommended to deploy a patch.

Detailsinfo

A vulnerability has been found in Microsoft Windows up to Server 2016 (Operating System) and classified as critical. Affected by this vulnerability is an unknown functionality in the library Win32k. The manipulation with an unknown input leads to a information disclosure vulnerability. The CWE definition for the vulnerability is CWE-200. The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

Microsoft Win32k in Windows Server 2008 SP2 and R2 SP1, Windows 7 SP1, Windows 8.1, Windows Server 2012 Gold and R2, Windows RT 8.1, Windows 10 Gold, 1511, 1607, and 1703, and Windows Server 2016 allows an information disclosure vulnerability when it fails to properly handle objects in memory, aka "Win32k Information Disclosure Vulnerability".

The bug was discovered 08/08/2017. The weakness was presented 08/08/2017 with Qihoo 360 as KB4034664 as confirmed security update guide (Website). It is possible to read the advisory at portal.msrc.microsoft.com. This vulnerability is known as CVE-2017-8666 since 05/03/2017. Attacking locally is a requirement. Additional levels of successful authentication are necessary for exploitation. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1592 according to MITRE ATT&CK. The advisory points out:

An information disclosure vulnerability exists when the win32k component improperly provides kernel information. An attacker who successfully exploited the vulnerability could obtain information to further compromise the user’s system.

The vulnerability scanner Nessus provides a plugin with the ID 102264 (KB4034658: Windows 10 Version 1607 and Windows Server 2016 August 2017 Cumulative Update), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Windows : Microsoft Bulletins and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 91405 (Microsoft Windows Security Update August 2017).

Applying the patch KB4034664 is able to eliminate this problem. The bugfix is ready for download at catalog.update.microsoft.com. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (102264) and SecurityFocus (BID 100089†). See VDB-102409, VDB-104989, VDB-104990 and VDB-104991 for similar entries. 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: 6.5
VulDB Meta Temp Score: 6.4

VulDB Base Score: 7.0
VulDB Temp Score: 6.7
VulDB Vector: 🔍
VulDB Reliability: 🔍

Vendor Base Score (Microsoft): 7.0
Vendor Vector (Microsoft): 🔍

NVD Base Score: 5.5
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
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Exploitinginfo

Class: Information disclosure
CWE: CWE-200 / 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: 102264
Nessus Name: KB4034658: Windows 10 Version 1607 and Windows Server 2016 August 2017 Cumulative Update
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 802136
OpenVAS Name: Microsoft Windows Multiple Vulnerabilites (KB4035055)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Patch: KB4034664

Timelineinfo

05/03/2017 🔍
08/08/2017 +97 days 🔍
08/08/2017 +0 days 🔍
08/08/2017 +0 days 🔍
08/08/2017 +0 days 🔍
08/08/2017 +0 days 🔍
08/08/2017 +0 days 🔍
08/09/2017 +1 days 🔍
01/08/2021 +1248 days 🔍

Sourcesinfo

Vendor: microsoft.com
Product: microsoft.com

Advisory: KB4034664
Researcher: fanxiaocao, pjf
Organization: Qihoo 360
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2017-8666 (🔍)
GCVE (CVE): GCVE-0-2017-8666
GCVE (VulDB): GCVE-100-105043

OVAL: 🔍

SecurityFocus: 100089 - Microsoft Windows Kernel 'Win32k.sys' CVE-2017-8666 Local Information Disclosure Vulnerability
SecurityTracker: 1039105

scip Labs: https://www.scip.ch/en/?labs.20161215
See also: 🔍

Entryinfo

Created: 08/09/2017 12:25
Updated: 01/08/2021 08:31
Changes: 08/09/2017 12:25 (90), 06/06/2020 09:21 (6), 01/08/2021 08:26 (6), 01/08/2021 08:31 (1)
Complete: 🔍
Cache ID: 216::103

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