CVE-2021-27063: Windows DNS Server Denial of Service Vulnerability

Published Mar 9, 2021
·
Updated

Windows DNS Server Denial of Service Vulnerability This CVE ID is unique from CVE-2021-26896.

Affected Software

27 affected componentsFixes available
Microsoft Windows Server 2008=r2-sp1
Microsoft Windows Server 2008=sp2
Microsoft Windows Server 2008 X86=sp2
Microsoft Windows Server 2012
Microsoft Windows Server 2012=r2
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 2008 R2<6.1.7601.24566
6.1.7601.24566
Microsoft Windows Server 2008 R2<6.1.7601.24566
6.1.7601.24566
Microsoft Windows Server 2008<6.0.6003.21070
6.0.6003.21070
Microsoft Windows Server 2008<6.0.6003.21070
6.0.6003.21070
Microsoft Windows Server 2012<6.2.9200.23298
6.2.9200.23298
Microsoft Windows Server 2012<6.2.9200.23298
6.2.9200.23298
Microsoft Windows Server 2008<6.0.6003.21070
6.0.6003.21070
Microsoft Windows Server 2008<6.0.6003.21070
6.0.6003.21070
Microsoft Windows Server 2012 R2<6.3.9600.19968
6.3.9600.19968
Microsoft Windows Server 2012 R2<6.3.9600.19968
6.3.9600.19968
Microsoft Windows Server 2016<10.0.14393.4283
10.0.14393.4283
Microsoft Windows Server 2016<10.0.14393.4283
10.0.14393.4283
Microsoft Windows Server=2004
10.0.19043.867
Microsoft Windows Server=20H2
10.0.19043.867
Microsoft Windows Server=1909
10.0.18363.1440
Microsoft Windows Server 2019<10.0.17763.1817
10.0.17763.1817
Microsoft Windows Server 2019<10.0.17763.1817
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 6.1.7601.24566Patch KB5000851
  2. Upgrade

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

    Fixed in 6.0.6003.21070Patch KB5000856
  3. Upgrade

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

    Fixed in 6.2.9200.23298Patch KB5000840
  4. Upgrade

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

    Fixed in 6.3.9600.19968Patch KB5000853
  5. Upgrade

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

    Fixed in 10.0.14393.4283Patch KB5000803
  6. Upgrade

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

    Fixed in 10.0.19043.867Patch KB5000802
  7. Upgrade

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

    Fixed in 10.0.18363.1440Patch KB5000808
  8. 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·03:49 PM
Data Sourced
via MITRE·03:49 PM
DescriptionSeverity
Data Sourced
via NVD·04:15 PM
RemedyDescriptionSeverityAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2021-27063?

CVE-2021-27063 is classified as a Denial of Service vulnerability.

2

How do I fix CVE-2021-27063?

To address CVE-2021-27063, apply the latest security updates provided by Microsoft for affected Windows Server versions.

3

Which systems are affected by CVE-2021-27063?

CVE-2021-27063 affects various versions of Microsoft Windows Server, including 2008, 2012, 2016, and 2019.

4

Can CVE-2021-27063 be exploited remotely?

Yes, CVE-2021-27063 can be exploited remotely to create a denial of service condition.

5

What are the potential impacts of CVE-2021-27063?

The potential impact of CVE-2021-27063 is service interruption due to the denial of service in affected Windows DNS servers.

Contact

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