CVE-2021-26891: Windows Container Execution Agent Elevation of Privilege Vulnerability

Published Mar 9, 2021
·
Updated

Windows Container Execution Agent Elevation of Privilege Vulnerability

Affected Software

30 affected componentsFixes available
Microsoft Windows 10=20h2
Microsoft Windows 10=1607
Microsoft Windows 10=1809
Microsoft Windows 10=1909
Microsoft Windows 10=2004
Microsoft Windows Server 2016
Microsoft Windows Server 2016=20h2
Microsoft Windows Server 2016=1909
Microsoft Windows Server 2016=2004
Microsoft Windows Server 2019
Microsoft Windows Server=20H2
10.0.19043.867
Microsoft Windows Server 2016<10.0.14393.4283
10.0.14393.4283
Microsoft Windows 10=1607
10.0.14393.4283
Microsoft Windows Server 2016<10.0.14393.4283
10.0.14393.4283
Microsoft Windows 10=2004
10.0.19043.867
Microsoft Windows 10=20H2
10.0.19043.867
Microsoft Windows 10=1607
10.0.14393.4283
Microsoft Windows Server=2004
10.0.19043.867
Microsoft Windows 10=20H2
10.0.19043.867
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=2004
10.0.19043.867
Microsoft Windows 10=2004
10.0.19043.867
Microsoft Windows 10=1909
10.0.18363.1440
Microsoft Windows 10=1809
10.0.17763.1817
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=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 10.0.14393.4283Patch KB5000803
  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 10.0.17763.1817Patch KB5000822

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·03:42 PM
Data Sourced
via MITRE·03:42 PM
DescriptionSeverity
Data Sourced
via NVD·04:15 PM
RemedyDescriptionSeverityAffected Software

Frequently Asked Questions

1

Does exploitation require network access or user interaction?

The CVSS vector indicates local attack access is required, and no user interaction is required. An attacker would also need low-level privileges before exploiting the issue.

2

What is the potential impact after successful exploitation?

Successful exploitation can affect confidentiality, integrity, and availability at a high level, according to the CVSS metrics. The issue is rated high severity with a CVSS 3.1 score of 7.8.

3

Which systems are identified as affected?

The listed affected products are Microsoft Windows 10, Windows Server 2016, Windows Server 2019, and Microsoft Windows Server. Specific affected versions or update levels are not provided in the available data.

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