CVE-2021-34444: Windows DNS Server Denial of Service Vulnerability

Published Jul 13, 2021
·
Updated

Windows DNS Server Denial of Service Vulnerability

Affected Software

24 affected componentsFixes available
Microsoft Windows Server 2008=sp2
Microsoft Windows Server 2008=r2-sp1
Microsoft Windows Server 2012
Microsoft Windows Server 2012=r2
Microsoft Windows Server 2016
Microsoft Windows Server 2016=20h2
Microsoft Windows Server 2016=2004
Microsoft Windows Server 2019
Microsoft Windows Server 2016<10.0.14393.4530
10.0.14393.4530
Microsoft Windows Server 2008<6.0.6003.21167
6.0.6003.21167
Microsoft Windows Server 2012 R2<6.3.9600.20069
6.3.9600.20069
Microsoft Windows Server 2012<6.2.9200.23409
6.2.9200.23409
Microsoft Windows Server 2008<6.0.6003.21167
6.0.6003.21167
Microsoft Windows Server 2012 R2<6.3.9600.20069
6.3.9600.20069
Microsoft Windows Server 2012<6.2.9200.23409
6.2.9200.23409
Microsoft Windows Server 2016<10.0.14393.4530
10.0.14393.4530
Microsoft Windows Server 2008 R2<6.1.7601.25661
6.1.7601.25661
Microsoft Windows Server 2008<6.0.6003.21167
6.0.6003.21167
Microsoft Windows Server 2008 R2<6.1.7601.25661
6.1.7601.25661
Microsoft Windows Server 2008<6.0.6003.21167
6.0.6003.21167
Microsoft Windows Server=20H2
10.0.19042.1110
Microsoft Windows Server 2019<10.0.17763.2061
10.0.17763.2061
Microsoft Windows Server=2004
10.0.19041.1110
Microsoft Windows Server 2019<10.0.17763.2061
10.0.17763.2061

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 6.3.9600.20069Patch KB5004285
  2. Upgrade

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

    Fixed in 10.0.14393.4530Patch KB5004238
  3. Upgrade

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

    Fixed in 6.0.6003.21167Patch KB5004299
  4. Upgrade

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

    Fixed in 6.2.9200.23409Patch KB5004302
  5. Upgrade

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

    Fixed in 6.1.7601.25661Patch KB5004307
  6. Upgrade

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

    Fixed in 10.0.17763.2061Patch KB5004244
  7. Upgrade

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

    Fixed in 10.0.19042.1110Patch KB5004237
  8. Upgrade

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

    Fixed in 10.0.19041.1110Patch KB5004237

Event History

Jul 13, 2021
CVE Published
via Microsoft·02:00 PM
Data Sourced
via Microsoft·02:00 PM
DescriptionSeverityWeaknessAffected Software
Updated
via Microsoft·02:00 PM
Affected Software
Updated
via Microsoft·02:00 PM
Description
Jul 16, 2021
CVE Published
via MITRE·08:19 PM
Data Sourced
via MITRE·08:19 PM
DescriptionSeverity
Data Sourced
via NVD·09:15 PM
RemedyDescriptionSeverityAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2021-34444?

CVE-2021-34444 has a severity rating of critical as it can lead to a denial of service in affected Windows DNS Servers.

2

How do I fix CVE-2021-34444?

To fix CVE-2021-34444, install the latest security updates provided by Microsoft for your Windows Server version.

3

Which versions of Windows are affected by CVE-2021-34444?

CVE-2021-34444 affects multiple versions of Windows Server including 2008, 2012, 2016, and 2019.

4

What exploitations can occur due to CVE-2021-34444?

Exploitation of CVE-2021-34444 can lead to a denial of service, causing affected systems to become unresponsive.

5

Is there a workaround for CVE-2021-34444?

Microsoft has not provided any specific workarounds for CVE-2021-34444, so applying security updates is recommended.

Contact

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