# CVE-2021-1723: ASP.NET Core and Visual Studio Denial of Service Vulnerability

Source: https://junglewise.ai/threats/cve-2021-1723-asp-net-core-and-visual-studio-denial-of-service-vulnerability  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2022-05-24  
License: CC BY 4.0 with a link back

CVE-2021-1723 · Severity: low · CVSS 3.1 · Published 2022-05-24

ASP.NET Core and Visual Studio Denial of Service Vulnerability

Technologies: [Microsoft.AspNetCore.App.Runtime.linux-arm (NuGet)](https://junglewise.ai/threats/technologies/microsoft-aspnetcore-app-runtime-linux-arm), [Microsoft.AspNetCore.App.Runtime.linux-arm64 (NuGet)](https://junglewise.ai/threats/technologies/microsoft-aspnetcore-app-runtime-linux-arm64), [Microsoft.AspNetCore.App.Runtime.linux-musl-arm (NuGet)](https://junglewise.ai/threats/technologies/microsoft-aspnetcore-app-runtime-linux-musl-arm), [Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 (NuGet)](https://junglewise.ai/threats/technologies/microsoft-aspnetcore-app-runtime-linux-musl-arm64), [Microsoft.AspNetCore.App.Runtime.linux-musl-x64 (NuGet)](https://junglewise.ai/threats/technologies/microsoft-aspnetcore-app-runtime-linux-musl-x64), [Microsoft.AspNetCore.App.Runtime.linux-x64 (NuGet)](https://junglewise.ai/threats/technologies/microsoft-aspnetcore-app-runtime-linux-x64), [Microsoft.AspNetCore.App.Runtime.osx-x64 (NuGet)](https://junglewise.ai/threats/technologies/microsoft-aspnetcore-app-runtime-osx-x64), [Microsoft.AspNetCore.App.Runtime.win-arm (NuGet)](https://junglewise.ai/threats/technologies/microsoft-aspnetcore-app-runtime-win-arm), [Microsoft.AspNetCore.App.Runtime.win-arm64 (NuGet)](https://junglewise.ai/threats/technologies/microsoft-aspnetcore-app-runtime-win-arm64), [Microsoft.AspNetCore.App.Runtime.win-x64 (NuGet)](https://junglewise.ai/threats/technologies/microsoft-aspnetcore-app-runtime-win-x64), [Microsoft.AspNetCore.App.Runtime.win-x86 (NuGet)](https://junglewise.ai/threats/technologies/microsoft-aspnetcore-app-runtime-win-x86), [Microsoft.AspNetCore.Server.Kestrel.Core (NuGet)](https://junglewise.ai/threats/technologies/microsoft-aspnetcore-server-kestrel-core). Vendors: [NuGet](https://junglewise.ai/threats/vendors/nuget).

## Quick answers

**Is CVE-2021-1723 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2021-1723 being exploited in the wild.

**How severe is CVE-2021-1723?** Low severity, with a CVSS score of 3.1, published 24 May 2022.

**Which products and versions are affected?** Microsoft.AspNetCore.App.Runtime.linux-arm (NuGet) ECOSYSTEM:introduced=3.1.0,fixed=3.1.11; Microsoft.AspNetCore.App.Runtime.linux-arm64 (NuGet) ECOSYSTEM:introduced=3.1.0,fixed=3.1.11; Microsoft.AspNetCore.App.Runtime.linux-musl-arm (NuGet) ECOSYSTEM:introduced=5.0.1,fixed=5.0.2; Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 (NuGet) ECOSYSTEM:introduced=3.1.0,fixed=3.1.11; and 8 more.

**Is there a fix for CVE-2021-1723?** Yes. Microsoft.AspNetCore.App.Runtime.linux-arm (NuGet): upgrade to 3.1.11 or later; Microsoft.AspNetCore.App.Runtime.linux-arm64 (NuGet): upgrade to 3.1.11 or later; Microsoft.AspNetCore.App.Runtime.linux-musl-arm (NuGet): upgrade to 5.0.2 or later; Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 (NuGet): upgrade to 3.1.11 or later; Microsoft.AspNetCore.App.Runtime.linux-musl-x64 (NuGet): upgrade to 3.1.11 or later; Microsoft.AspNetCore.App.Runtime.linux-x64 (NuGet): upgrade to 3.1.11 or later; Microsoft.AspNetCore.App.Runtime.osx-x64 (NuGet): upgrade to 3.1.11 or later; Microsoft.AspNetCore.App.Runtime.win-arm (NuGet): upgrade to 3.1.11 or later; Microsoft.AspNetCore.App.Runtime.win-arm64 (NuGet): upgrade to 3.1.11 or later; Microsoft.AspNetCore.App.Runtime.win-x64 (NuGet): upgrade to 3.1.11 or later; Microsoft.AspNetCore.App.Runtime.win-x86 (NuGet): upgrade to 3.1.11 or later; Microsoft.AspNetCore.Server.Kestrel.Core (NuGet): upgrade to 2.1.25 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2021-1723?** Check whether you run Microsoft.AspNetCore.App.Runtime.linux-arm (NuGet), Microsoft.AspNetCore.App.Runtime.linux-arm64 (NuGet), Microsoft.AspNetCore.App.Runtime.linux-musl-arm (NuGet) or one of the others listed at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- Microsoft.AspNetCore.App.Runtime.linux-arm (NuGet): upgrade to 3.1.11 or later

  ```sh
  dotnet add package Microsoft.AspNetCore.App.Runtime.linux-arm --version 3.1.11
  ```

- Microsoft.AspNetCore.App.Runtime.linux-arm64 (NuGet): upgrade to 3.1.11 or later

  ```sh
  dotnet add package Microsoft.AspNetCore.App.Runtime.linux-arm64 --version 3.1.11
  ```

- Microsoft.AspNetCore.App.Runtime.linux-musl-arm (NuGet): upgrade to 5.0.2 or later

  ```sh
  dotnet add package Microsoft.AspNetCore.App.Runtime.linux-musl-arm --version 5.0.2
  ```

- Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 (NuGet): upgrade to 3.1.11 or later

  ```sh
  dotnet add package Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 --version 3.1.11
  ```

- Microsoft.AspNetCore.App.Runtime.linux-musl-x64 (NuGet): upgrade to 3.1.11 or later

  ```sh
  dotnet add package Microsoft.AspNetCore.App.Runtime.linux-musl-x64 --version 3.1.11
  ```

- Microsoft.AspNetCore.App.Runtime.linux-x64 (NuGet): upgrade to 3.1.11 or later

  ```sh
  dotnet add package Microsoft.AspNetCore.App.Runtime.linux-x64 --version 3.1.11
  ```

- Microsoft.AspNetCore.App.Runtime.osx-x64 (NuGet): upgrade to 3.1.11 or later

  ```sh
  dotnet add package Microsoft.AspNetCore.App.Runtime.osx-x64 --version 3.1.11
  ```

- Microsoft.AspNetCore.App.Runtime.win-arm (NuGet): upgrade to 3.1.11 or later

  ```sh
  dotnet add package Microsoft.AspNetCore.App.Runtime.win-arm --version 3.1.11
  ```

- Microsoft.AspNetCore.App.Runtime.win-arm64 (NuGet): upgrade to 3.1.11 or later

  ```sh
  dotnet add package Microsoft.AspNetCore.App.Runtime.win-arm64 --version 3.1.11
  ```

- Microsoft.AspNetCore.App.Runtime.win-x64 (NuGet): upgrade to 3.1.11 or later

  ```sh
  dotnet add package Microsoft.AspNetCore.App.Runtime.win-x64 --version 3.1.11
  ```

- Microsoft.AspNetCore.App.Runtime.win-x86 (NuGet): upgrade to 3.1.11 or later

  ```sh
  dotnet add package Microsoft.AspNetCore.App.Runtime.win-x86 --version 3.1.11
  ```

- Microsoft.AspNetCore.Server.Kestrel.Core (NuGet): upgrade to 2.1.25 or later

  ```sh
  dotnet add package Microsoft.AspNetCore.Server.Kestrel.Core --version 2.1.25
  ```


## Affected products

- Microsoft.AspNetCore.App.Runtime.linux-arm (NuGet) ECOSYSTEM:introduced=3.1.0,fixed=3.1.11
- Microsoft.AspNetCore.App.Runtime.linux-arm64 (NuGet) ECOSYSTEM:introduced=3.1.0,fixed=3.1.11
- Microsoft.AspNetCore.App.Runtime.linux-musl-arm (NuGet) ECOSYSTEM:introduced=5.0.1,fixed=5.0.2
- Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 (NuGet) ECOSYSTEM:introduced=3.1.0,fixed=3.1.11
- Microsoft.AspNetCore.App.Runtime.linux-musl-x64 (NuGet) ECOSYSTEM:introduced=3.1.0,fixed=3.1.11
- Microsoft.AspNetCore.App.Runtime.linux-x64 (NuGet) ECOSYSTEM:introduced=3.1.0,fixed=3.1.11
- Microsoft.AspNetCore.App.Runtime.osx-x64 (NuGet) ECOSYSTEM:introduced=3.1.0,fixed=3.1.11
- Microsoft.AspNetCore.App.Runtime.win-arm (NuGet) ECOSYSTEM:introduced=3.1.0,fixed=3.1.11
- Microsoft.AspNetCore.App.Runtime.win-arm64 (NuGet) ECOSYSTEM:introduced=3.1.0,fixed=3.1.11
- Microsoft.AspNetCore.App.Runtime.win-x64 (NuGet) ECOSYSTEM:introduced=3.1.0,fixed=3.1.11
- Microsoft.AspNetCore.App.Runtime.win-x86 (NuGet) ECOSYSTEM:introduced=3.1.0,fixed=3.1.11
- Microsoft.AspNetCore.Server.Kestrel.Core (NuGet) ECOSYSTEM:introduced=0,fixed=2.1.25

## Identifiers

- CVE-2021-1723
- GHSA-242j-2gm6-5rwx

## Related threats

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- [Microsoft ASP.NET Core Localization denial of service](https://junglewise.ai/threats/cve-2026-96236-microsoft-security-advisory-asp-net-core-denial-of-service)
- [Microsoft ASP.NET Core authorization bypass in Blazor AuthorizeRouteView](https://junglewise.ai/threats/cve-2026-70183-microsoft-security-advisory-asp-net-core-security-feature-bypass)
- [ASP.NET Core denial of service in FormPipeReader](https://junglewise.ai/threats/cve-2026-70196-microsoft-security-advisory-asp-net-core-denial-of-service)