Microsoft Windows vulnerabilities

Microsoft fixes multiple vulnerabilities in Windows.

A malicious entity could potentially exploit the vulnerabilities to:

• Cause a Denial of Service,
• Bypass security measures,
• Run arbitrary code,
• Obtain increased rights,
• To gain access to sensitive data,
• To pretend to be another user.

The vulnerabilities with attributes CVE-2021-31166 (CVSS 9.80) and CVE-2021-28476 (CVSS 9.90) have been rated “Critical” by Microsoft.

The vulnerability with attribute CVE-2021-31166 resides in the HTTP Protocol Stack. A remote malicious entity could exploit this vulnerability by sending specially prepared packets to the HTTP server to execute arbitrary code. Proof-of-Concept code was released for this vulnerability on 16-05-2021. The Proof-of-Concept code shows that it is possible to perform a Denial-of-Service.

The vulnerability with attribute CVE-2021-28476 resides in Hyper-V where a Hyper-V VM could force the Hyper-V host kernel to read an arbitrary, potentially invalid address. The content of the address will not reach the Hyper-V VM. In most cases this will lead to a Denial-of-Service of the Hyper-V host (bug check). Microsoft indicates that it is also possible to compromise the security of the Hyper-V host by reading the registry of specific attached peripherals.

Below is an overview of the various vulnerabilities described per component and their impact:

Jet Red and Access Connectivity:

CVE-ID: CVE-2021-28455
CVSS: 8,80
Impact: Arbitrary code execution

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Windows RDP Client:

CVE-ID: CVE-2021-31186

CVSS: 7,40

Impact: Access to sensitive data

Windows SMB:

CVE-ID: CVE-2021-31205
CVSS: 4,30
Impact: Circumvention of security measure

Microsoft Bluetooth Driver:

CVE-ID: CVE-2021-31182
CVSS: 7,10
Impact: Present as another user

Windows Container Isolation FS Filter Driver:

CVE-ID: CVE-2021-31190
CVSS: 7,80
Impact: Obtaining Increased Rights

Windows Container Manager Service:

CVE-ID: CVE-2021-31165CVE-2021-31167
CVE-2021-31168
CVE-2021-31169
CVE-2021-31208

CVSS: all 7,80
Impact: all obtaining Increased Rights

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HTTP.sys:

CVE-ID: CVE-2021-31166
CVSS: 9,80
Impact: Arbitrary code execution

Role: Hyper-V:

CVE-ID: CVE-2021-28476
CVSS: 9,90
Impact: Arbitrary code execution

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Windows SSDP Service:

CVE-ID: CVE-2021-31193
CVSS: 7,80
Impact: Obtaining Increased Rights

Microsoft Windows IrDA:

CVE-ID: CVE-2021-31184
CVSS: 5,40
Impact: Access to sensitive data

Windows Wireless Networking:

CVE-ID: CVE-2020-24588
CVE-2020-26144
CVSS: both 6,50
Impact: Both present as another user

CVE-ID: CVE-2020-24587
CVSS 6,50
Impact: Access to sensitive data

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Windows Projected File System FS Filter:

CVE-ID: CVE-2021-31191

CVSS: 5,50

Impact:Access to sensitive data

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Windows OLE:

CVE-ID: CVE-2021-31194

CVSS: 7,80

Impact: Arbitrary code execution

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Windows WalletService:

CVE-ID: CVE-2021-31187
CVSS: 7,80
Impact: Obtaining Increased Rights

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Windows Desktop Bridge:

CVE-ID: CVE-2021-31185
CVSS: 5,50
Impact: Denial-of-Service

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Windows CSC Service:

CVE-ID: CVE-2021-28479
CVSS: 5,50
Impact: Access to sensitive data

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Microsoft Windows Codecs Library:

CVE-ID: CVE-2021-31192
CVE-2021-28465

CVSS: both 7,80

Impact: Both arbitrary code execution

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Microsoft Graphics Component:

CVE-ID: CVE-2021-31170
CVE-2021-31188
CVSS: both 7,80
Impact: both obtaining Increased Rights

Microsoft has released updates that address the vulnerabilities described. We recommend that you install these updates. More information about the vulnerabilities, the installation of the updates and any workarounds, see the Microsoft website.