CVE-2021-26863: Windows Win32k Elevation of Privilege Vulnerability

Published Mar 9, 2021
·
Updated

Windows Win32k Elevation of Privilege Vulnerability

Affected Software

28 affected componentsFixes available
Microsoft Windows 10=20h2
Microsoft Windows 10=1803
Microsoft Windows 10=1809
Microsoft Windows 10=1909
Microsoft Windows 10=2004
Microsoft Windows Server 2016=20h2
Microsoft Windows Server 2016=1909
Microsoft Windows Server 2016=2004
Microsoft Windows Server 2019
Microsoft Windows 10=2004
10.0.19043.867
Microsoft Windows Server=20H2
10.0.19043.867
Microsoft Windows 10=20H2
10.0.19043.867
Microsoft Windows 10=20H2
10.0.19043.867
Microsoft Windows 10=2004
10.0.19043.867
Microsoft Windows Server=2004
10.0.19043.867
Microsoft Windows 10=2004
10.0.19043.867
Microsoft Windows Server 2019<10.0.17763.1817
10.0.17763.1817
Microsoft Windows Server 2019<10.0.17763.1817
10.0.17763.1817
Microsoft Windows 10=1909
10.0.18363.1440
Microsoft Windows 10=1909
10.0.18363.1440
Microsoft Windows Server=1909
10.0.18363.1440
Microsoft Windows 10=1909
10.0.18363.1440
Microsoft Windows 10=1803
10.0.17134.2087
Microsoft Windows 10=1809
10.0.17763.1817
Microsoft Windows 10=1803
10.0.17134.2087
Microsoft Windows 10=1803
10.0.17134.2087
Microsoft Windows 10=1809
10.0.17763.1817
Microsoft Windows 10=1809
10.0.17763.1817

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.19043.867Patch KB5000802
  2. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.17763.1817Patch KB5000822
  3. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.18363.1440Patch KB5000808
  4. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.17134.2087Patch KB5000809

Event History

Mar 9, 2021
CVE Published
via Microsoft·04:00 PM
Data Sourced
via Microsoft·04:00 PM
DescriptionSeverityWeakness
Data Sourced
via Microsoft·04:00 PM
Affected Software
Updated
via Microsoft·04:00 PM
Description
Mar 11, 2021
CVE Published
via MITRE·03:37 PM
Data Sourced
via MITRE·03:37 PM
DescriptionSeverity
Data Sourced
via NVD·04:15 PM
RemedyDescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

Who is exposed to this vulnerability?

The affected software listed is Microsoft Windows 10, Windows Server 2016, and Windows Server 2019. Exploitation is local, so systems are exposed when an attacker can execute code locally with an existing low-privileged account or process.

2

What access and conditions does an attacker need?

The CVSS vector indicates local access, low privileges, and no user interaction are required. Exploitation has high attack complexity, and successful exploitation can affect confidentiality, integrity, and availability.

Contact

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