Microsoft Windows up to Server 2016 Win32k access control

CVSS Meta Temp Score
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CTI Interest Score
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7.3$5k-$25k0.00

A vulnerability was found in Microsoft Windows up to Server 2016 (Operating System). It has been declared as critical. This vulnerability affects an unknown part in the library Win32k. The manipulation with an unknown input leads to a access control vulnerability. The CWE definition for the vulnerability is CWE-264. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

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 elevation of privilege vulnerability when it fails to properly handle objects in memory, aka "Win32k Elevation of Privilege Vulnerability".

The bug was discovered 08/08/2017. The weakness was published 08/08/2017 with Tencent as KB4034674 as confirmed security update guide (Website). The advisory is available at portal.msrc.microsoft.com. This vulnerability was named CVE-2017-8593 since 05/03/2017. The attack can be initiated remotely. A single authentication is necessary for exploitation. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $5k-$25k at the moment (estimation calculated on 01/07/2021). This vulnerability is assigned to T1068 by the MITRE ATT&CK project. The advisory points out:

An elevation of privilege vulnerability exists in Windows when the Win32k component fails to properly handle objects in memory. An attacker who successfully exploited this vulnerability could run arbitrary code in kernel mode. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.

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 KB4034674 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 vulnerability database at Tenable (102264). Similar entries are available at 102409, 104989, 104990 and 104991.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
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CVSSv3info

VulDB Meta Base Score: 7.6
VulDB Meta Temp Score: 7.5

VulDB Base Score: 8.8
VulDB Temp Score: 8.4
VulDB Vector: 🔍
VulDB Reliability: 🔍

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

NVD Base Score: 7.0
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
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Exploitinginfo

Class: Access control
CWE: CWE-264
ATT&CK: T1068

Local: No
Remote: Yes

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: 🔍
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Countermeasuresinfo

Recommended: Patch
Status: 🔍

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

Patch: KB4034674

Timelineinfo

05/03/2017 🔍
08/08/2017 +97 days 🔍
08/08/2017 +0 days 🔍
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08/08/2017 +0 days 🔍
08/08/2017 +0 days 🔍
08/08/2017 +0 days 🔍
08/09/2017 +0 days 🔍
01/07/2021 +1247 days 🔍

Sourcesinfo

Vendor: microsoft.com
Product: microsoft.com

Advisory: KB4034674
Researcher: WenQunWang
Organization: Tencent
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2017-8593 (🔍)
OVAL: 🔍

SecurityTracker: 1039105
SecurityFocus: 100032 - Microsoft Windows Kernel 'Win32k.sys' CVE-2017-8593 Local Privilege Escalation Vulnerability

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

Entryinfo

Created: 08/09/2017 11:42
Updated: 01/07/2021 16:54
Changes: 08/09/2017 11:42 (91), 06/06/2020 08:47 (6), 01/07/2021 16:47 (3), 01/07/2021 16:54 (1)
Complete: 🔍

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