CVE-2021-26423: .NET Core and Visual Studio Denial of Service Vulnerability

Published Aug 10, 2021
·
Updated

.NET Core and Visual Studio Denial of Service Vulnerability

Affected Software

19 affected componentsFixes available
Microsoft .NET>=5.0<=5.0.8
Microsoft .NET Core>=2.1<=2.1.28
Microsoft .NET Core>=3.1<=3.1.17
Microsoft PowerShell Core>=7.0<7.0.7
Microsoft PowerShell Core>=7.1<7.1.4
Microsoft Visual Studio 2017>=15.0<=15.9
Microsoft Visual Studio 2019>=16.0<=16.10
Microsoft Visual Studio 2019 Macos=8.10
Microsoft .NET Core=2.1
2.1.30
Microsoft Visual Studio 2019 (includes 16.0 - 16.9)=16.10
16.10.5
Microsoft Visual Studio 2019 (includes 16.0 - 16.8)=16.9
16.9.10
Microsoft Visual Studio 2019 (includes 16.0 - 16.3)=16.4
16.4.25
Microsoft .NET Core=3.1
3.1.18
Microsoft PowerShell Core=7.1
7.1.4
Microsoft Visual Studio 2019 (includes 16.0 – 16.6)=16.7
16.7.18
Microsoft Visual Studio 2017 (includes 15.0 - 15.8)=15.9
15.9.38
Microsoft .NET 5.0<5.0.9
5.0.9
Microsoft PowerShell Core=7.0
7.0.7
Microsoft Visual Studio 2019 for Mac=8.10
8.10.7

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 2.1.30
  2. Upgrade

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

    Fixed in 16.10.5
  3. Upgrade

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

    Fixed in 16.9.10
  4. Upgrade

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

    Fixed in 3.1.18
  5. Upgrade

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

    Fixed in 16.4.25
  6. Upgrade

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

    Fixed in 16.7.18
  7. Upgrade

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

    Fixed in 15.9.38
  8. Upgrade

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

    Fixed in 7.1.4
  9. Upgrade

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

    Fixed in 5.0.9
  10. Upgrade

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

    Fixed in 7.0.7
  11. Upgrade

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

    Fixed in 8.10.7

Event History

Aug 10, 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
Aug 12, 2021
CVE Published
via MITRE·06:11 PM
Data Sourced
via MITRE·06:11 PM
DescriptionSeverity
Data Sourced
via NVD·06:15 PM
RemedyDescriptionSeverityAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2021-26423?

The severity of CVE-2021-26423 is high with a CVSS score of 7.5.

2

Which software versions are affected by CVE-2021-26423?

CVE-2021-26423 affects Microsoft .NET versions 5.0 and earlier, Microsoft .NET Core versions 2.1 and 3.1, Microsoft PowerShell Core versions 7.0 and 7.1, and Microsoft Visual Studio versions 15.0 to 15.9 and 16.0 to 16.10.

3

What is the vulnerability description of CVE-2021-26423?

CVE-2021-26423 is a denial of service vulnerability in .NET Core and Visual Studio.

4

How can I fix CVE-2021-26423?

To fix CVE-2021-26423, it is recommended to update to the latest patched versions of the affected software.

5

Where can I find more information about CVE-2021-26423?

You can find more information about CVE-2021-26423 in the Microsoft Security Guidance Advisory for CVE-2021-26423: [link](https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-26423)

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