CVE-2021-34499: 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 2019<10.0.17763.2061
10.0.17763.2061
Microsoft Windows Server=20H2
10.0.19042.1110
Microsoft Windows Server=2004
10.0.19041.1110
Microsoft Windows Server 2019<10.0.17763.2061
10.0.17763.2061
Microsoft Windows Server 2016<10.0.14393.4530
10.0.14393.4530
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 R2<6.3.9600.20069
6.3.9600.20069
Microsoft Windows Server 2008 R2<6.1.7601.25661
6.1.7601.25661
Microsoft Windows Server 2008 R2<6.1.7601.25661
6.1.7601.25661
Microsoft Windows Server 2012<6.2.9200.23409
6.2.9200.23409
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 2008<6.0.6003.21167
6.0.6003.21167
Microsoft Windows Server 2008<6.0.6003.21167
6.0.6003.21167

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 10.0.17763.2061Patch KB5004244
  2. Upgrade

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

    Fixed in 10.0.19041.1110Patch KB5004237
  3. Upgrade

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

    Fixed in 10.0.19042.1110Patch KB5004237
  4. Upgrade

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

    Fixed in 10.0.14393.4530Patch KB5004238
  5. Upgrade

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

    Fixed in 6.0.6003.21167Patch KB5004299
  6. Upgrade

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

    Fixed in 6.3.9600.20069Patch KB5004285
  7. Upgrade

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

    Fixed in 6.1.7601.25661Patch KB5004307
  8. Upgrade

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

    Fixed in 6.2.9200.23409Patch KB5004302

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 14, 2021
CVE Published
via MITRE·05:54 PM
Data Sourced
via MITRE·05:54 PM
DescriptionSeverity
Data Sourced
via NVD·06:15 PM
RemedyDescriptionSeverityAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2021-34499?

CVE-2021-34499 has a severity rating of Important as it can lead to a denial of service on affected Windows DNS servers.

2

Which versions of Windows are affected by CVE-2021-34499?

CVE-2021-34499 affects multiple versions of Windows Server, including 2008, 2012, 2016, and 2019.

3

How do I fix CVE-2021-34499?

To fix CVE-2021-34499, you should apply the latest security patches provided by Microsoft for your affected Windows Server version.

4

What type of attack does CVE-2021-34499 enable?

CVE-2021-34499 enables a denial of service attack that can disrupt DNS services on vulnerable Windows servers.

5

Is there a workaround for CVE-2021-34499?

Currently, the only recommended mitigation for CVE-2021-34499 is to apply the appropriate security updates from Microsoft.

Contact

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