CVE-2021-1721 — Denial of service in...

MEDIUM

Denial of service in .NET core

Published May 24, 2022Updated November 29, 2024Source: osv

Summary

.NET Core and Visual Studio Denial of Service Vulnerability due to a vulnerability which exists when creating HTTPS web request during X509 certificate chain building.

Advisory Timeline

First published May 24, 2022 (1602 days ago).
Last revised November 29, 2024 — 919 days after initial publication.

Remediation

Upgrade to the fixed version using your package manager.

NuGet

Update Microsoft.NETCore.App.Runtime.Mono.LLVM.AOT.osx-x64 to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.Mono.LLVM.AOT.osx-x64 --version 5.0.3

NuGet

Update Microsoft.NETCore.App.Runtime.osx-x64 to 3.1.12 or later

dotnet add package Microsoft.NETCore.App.Runtime.osx-x64 --version 3.1.12

NuGet

Update Microsoft.NETCore.App.Runtime.android-arm to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.android-arm --version 5.0.3

NuGet

Update Microsoft.NETCore.App.Runtime.tvos-x64 to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.tvos-x64 --version 5.0.3

NuGet

Update Microsoft.NETCore.App.Runtime.linux-musl-arm64 to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.linux-musl-arm64 --version 5.0.3

NuGet

Update Microsoft.NETCore.App.Host.rhel.6-x64 to 3.1.12 or later

dotnet add package Microsoft.NETCore.App.Host.rhel.6-x64 --version 3.1.12

NuGet

Update Microsoft.NETCore.App.Host.linux-arm to 3.1.12 or later

dotnet add package Microsoft.NETCore.App.Host.linux-arm --version 3.1.12

NuGet

Update Microsoft.NETCore.App.Runtime.Mono.osx-x64 to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.Mono.osx-x64 --version 5.0.3

NuGet

Update Microsoft.NETCore.App.Runtime.linux-musl-x64 to 3.1.12 or later

dotnet add package Microsoft.NETCore.App.Runtime.linux-musl-x64 --version 3.1.12

NuGet

Update Microsoft.NETCore.App.Runtime.osx-x64 to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.osx-x64 --version 5.0.3

NuGet

Update Microsoft.NETCore.App.Runtime.Mono.LLVM.osx-x64 to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.Mono.LLVM.osx-x64 --version 5.0.3

NuGet

Update Microsoft.NETCore.App.Runtime.linux-musl-x64 to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.linux-musl-x64 --version 5.0.3

NuGet

Update Microsoft.NETCore.App.Runtime.linux-musl-arm to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.linux-musl-arm --version 5.0.3

NuGet

Update Microsoft.NETCore.App.Runtime.linux-arm64 to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.linux-arm64 --version 5.0.3

NuGet

Update Microsoft.NETCore.App.Host.linux-arm64 to 3.1.12 or later

dotnet add package Microsoft.NETCore.App.Host.linux-arm64 --version 3.1.12

NuGet

Update Microsoft.NETCore.App.Host.linux-musl-arm64 to 3.1.12 or later

dotnet add package Microsoft.NETCore.App.Host.linux-musl-arm64 --version 3.1.12

NuGet

Update Microsoft.NETCore.App.Runtime.win-x86 to 3.1.12 or later

dotnet add package Microsoft.NETCore.App.Runtime.win-x86 --version 3.1.12

NuGet

Update Microsoft.NETCore.App.Host.win-x64 to 3.1.12 or later

dotnet add package Microsoft.NETCore.App.Host.win-x64 --version 3.1.12

NuGet

Update Microsoft.NETCore.App.Runtime.linux-arm to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.linux-arm --version 5.0.3

NuGet

Update Microsoft.NETCore.App.Runtime.ios-x86 to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.ios-x86 --version 5.0.3

NuGet

Update Microsoft.NETCore.App.Runtime.Mono.LLVM.linux-x64 to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.Mono.LLVM.linux-x64 --version 5.0.3

NuGet

Update Microsoft.NETCore.App.Runtime.win-x86 to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.win-x86 --version 5.0.3

NuGet

Update Microsoft.NETCore.App.Runtime.win-x64 to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.win-x64 --version 5.0.3

NuGet

Update Microsoft.NETCore.App.Runtime.linux-musl-arm64 to 3.1.12 or later

dotnet add package Microsoft.NETCore.App.Runtime.linux-musl-arm64 --version 3.1.12

NuGet

Update Microsoft.NETCore.App.Runtime.win-arm64 to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.win-arm64 --version 5.0.3

NuGet

Update Microsoft.NETCore.App to 2.1.25 or later

dotnet add package Microsoft.NETCore.App --version 2.1.25

NuGet

Update Microsoft.NETCore.App.Runtime.win-arm64 to 3.1.12 or later

dotnet add package Microsoft.NETCore.App.Runtime.win-arm64 --version 3.1.12

NuGet

Update Microsoft.NETCore.App.Host.linux-musl-x64 to 3.1.12 or later

dotnet add package Microsoft.NETCore.App.Host.linux-musl-x64 --version 3.1.12

NuGet

Update Microsoft.NETCore.App.Runtime.Mono.LLVM.AOT.linux-arm64 to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.Mono.LLVM.AOT.linux-arm64 --version 5.0.3

NuGet

Update Microsoft.NETCore.App.Runtime.linux-arm64 to 3.1.12 or later

dotnet add package Microsoft.NETCore.App.Runtime.linux-arm64 --version 3.1.12

NuGet

Update Microsoft.NETCore.App.Runtime.Mono.linux-arm64 to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.Mono.linux-arm64 --version 5.0.3

NuGet

Update Microsoft.NETCore.App.Runtime.android-x64 to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.android-x64 --version 5.0.3

NuGet

Update Microsoft.NETCore.App.Runtime.android-arm64 to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.android-arm64 --version 5.0.3

NuGet

Update Microsoft.NETCore.App.Runtime.tvos-arm64 to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.tvos-arm64 --version 5.0.3

NuGet

Update Microsoft.NETCore.App.Runtime.ios-x64 to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.ios-x64 --version 5.0.3

NuGet

Update Microsoft.NETCore.App.Runtime.linux-arm to 3.1.12 or later

dotnet add package Microsoft.NETCore.App.Runtime.linux-arm --version 3.1.12

NuGet

Update Microsoft.NETCore.App.Runtime.Mono.linux-x64 to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.Mono.linux-x64 --version 5.0.3

NuGet

Update Microsoft.NETCore.App.Runtime.linux-x64 to 3.1.12 or later

dotnet add package Microsoft.NETCore.App.Runtime.linux-x64 --version 3.1.12

NuGet

Update Microsoft.NETCore.App.Runtime.browser-wasm to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.browser-wasm --version 5.0.3

NuGet

Update Microsoft.NETCore.App.Host.win-x86 to 3.1.12 or later

dotnet add package Microsoft.NETCore.App.Host.win-x86 --version 3.1.12

NuGet

Update Microsoft.NETCore.App.Runtime.android-x86 to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.android-x86 --version 5.0.3

NuGet

Update Microsoft.NETCore.App.Runtime.Mono.LLVM.AOT.linux-x64 to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.Mono.LLVM.AOT.linux-x64 --version 5.0.3

NuGet

Update Microsoft.NETCore.App.Host.osx-x64 to 3.1.12 or later

dotnet add package Microsoft.NETCore.App.Host.osx-x64 --version 3.1.12

NuGet

Update Microsoft.NETCore.App.Runtime.linux-x64 to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.linux-x64 --version 5.0.3

NuGet

Update Microsoft.NETCore.App.Runtime.Mono.LLVM.linux-arm64 to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.Mono.LLVM.linux-arm64 --version 5.0.3

NuGet

Update Microsoft.NETCore.App.Runtime.win-arm to 3.1.12 or later

dotnet add package Microsoft.NETCore.App.Runtime.win-arm --version 3.1.12

NuGet

Update Microsoft.NETCore.App.Runtime.Mono.linux-musl-x64 to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.Mono.linux-musl-x64 --version 5.0.3

NuGet

Update Microsoft.NETCore.App.Runtime.win-arm to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.win-arm --version 5.0.3

NuGet

Update Microsoft.NETCore.App.Runtime.rhel.6-x64 to 3.1.12 or later

dotnet add package Microsoft.NETCore.App.Runtime.rhel.6-x64 --version 3.1.12

NuGet

Update Microsoft.NETCore.App.Host.win-arm to 3.1.12 or later

dotnet add package Microsoft.NETCore.App.Host.win-arm --version 3.1.12

NuGet

Update Microsoft.NETCore.App.Runtime.win-x64 to 3.1.12 or later

dotnet add package Microsoft.NETCore.App.Runtime.win-x64 --version 3.1.12

NuGet

Update Microsoft.NETCore.App.Host.linux-x64 to 3.1.12 or later

dotnet add package Microsoft.NETCore.App.Host.linux-x64 --version 3.1.12

NuGet

Update Microsoft.NETCore.App.Runtime.ios-arm to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.ios-arm --version 5.0.3

NuGet

Update Microsoft.NETCore.App.Host.win-arm64 to 3.1.12 or later

dotnet add package Microsoft.NETCore.App.Host.win-arm64 --version 3.1.12

NuGet

Update Microsoft.NETCore.App.Runtime.Mono.linux-arm to 5.0.3 or later

dotnet add package Microsoft.NETCore.App.Runtime.Mono.linux-arm --version 5.0.3

After upgrading, run your dependency scanner again to confirm the vulnerability is resolved.

Affected Packages (55)

Affects 1 ecosystem: nuget (45).

Package	Ecosystem	Affected	Fixed In
Microsoft.NETCore.App.Runtime.Mono.LLVM.AOT.osx-x64	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3
Microsoft.NETCore.App.Runtime.osx-x64	nuget	3.1.0, 3.1.1, 3.1.10, 3.1.11 (+8 more)	3.1.12
Microsoft.NETCore.App.Runtime.android-arm	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3
Microsoft.NETCore.App.Runtime.tvos-x64	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3
Microsoft.NETCore.App.Runtime.linux-musl-arm64	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3
Microsoft.NETCore.App.Host.rhel.6-x64	nuget	3.1.0, 3.1.1, 3.1.10, 3.1.11 (+8 more)	3.1.12
Microsoft.NETCore.App.Host.linux-arm	nuget	3.1.0, 3.1.1, 3.1.10, 3.1.11 (+8 more)	3.1.12
Microsoft.NETCore.App.Runtime.Mono.osx-x64	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3
Microsoft.NETCore.App.Runtime.linux-musl-x64	nuget	3.1.0, 3.1.1, 3.1.10, 3.1.11 (+8 more)	3.1.12
Microsoft.NETCore.App.Runtime.osx-x64	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3
Microsoft.NETCore.App.Runtime.Mono.LLVM.osx-x64	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3
Microsoft.NETCore.App.Runtime.linux-musl-x64	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3
Microsoft.NETCore.App.Runtime.linux-musl-arm	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3
Microsoft.NETCore.App.Runtime.linux-arm64	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3
Microsoft.NETCore.App.Host.linux-arm64	nuget	3.1.0, 3.1.1, 3.1.10, 3.1.11 (+8 more)	3.1.12
Microsoft.NETCore.App.Host.linux-musl-arm64	nuget	3.1.0, 3.1.1, 3.1.10, 3.1.11 (+8 more)	3.1.12
Microsoft.NETCore.App.Runtime.win-x86	nuget	3.1.0, 3.1.1, 3.1.10, 3.1.11 (+8 more)	3.1.12
Microsoft.NETCore.App.Host.win-x64	nuget	3.1.0, 3.1.1, 3.1.10, 3.1.11 (+8 more)	3.1.12
Microsoft.NETCore.App.Runtime.linux-arm	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3
Microsoft.NETCore.App.Runtime.ios-x86	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3
Microsoft.NETCore.App.Runtime.Mono.LLVM.linux-x64	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3
Microsoft.NETCore.App.Runtime.win-x86	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3
Microsoft.NETCore.App.Runtime.win-x64	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3
Microsoft.NETCore.App.Runtime.linux-musl-arm64	nuget	3.1.0, 3.1.1, 3.1.10, 3.1.11 (+8 more)	3.1.12
Microsoft.NETCore.App.Runtime.win-arm64	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3
Microsoft.NETCore.App	nuget	2.1.0, 2.1.1, 2.1.10, 2.1.11 (+21 more)	2.1.25
Microsoft.NETCore.App.Runtime.win-arm64	nuget	3.1.0, 3.1.1, 3.1.10, 3.1.11 (+8 more)	3.1.12
Microsoft.NETCore.App.Host.linux-musl-x64	nuget	3.1.0, 3.1.1, 3.1.10, 3.1.11 (+8 more)	3.1.12
Microsoft.NETCore.App.Runtime.Mono.LLVM.AOT.linux-arm64	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3
Microsoft.NETCore.App.Runtime.linux-arm64	nuget	3.1.0, 3.1.1, 3.1.10, 3.1.11 (+8 more)	3.1.12
Microsoft.NETCore.App.Runtime.Mono.linux-arm64	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3
Microsoft.NETCore.App.Runtime.android-x64	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3
Microsoft.NETCore.App.Runtime.android-arm64	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3
Microsoft.NETCore.App.Runtime.tvos-arm64	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3
Microsoft.NETCore.App.Runtime.ios-x64	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3
Microsoft.NETCore.App.Runtime.linux-arm	nuget	3.1.0, 3.1.1, 3.1.10, 3.1.11 (+8 more)	3.1.12
Microsoft.NETCore.App.Runtime.Mono.linux-x64	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3
Microsoft.NETCore.App.Runtime.linux-x64	nuget	3.1.0, 3.1.1, 3.1.10, 3.1.11 (+8 more)	3.1.12
Microsoft.NETCore.App.Runtime.browser-wasm	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3
Microsoft.NETCore.App.Host.win-x86	nuget	3.1.0, 3.1.1, 3.1.10, 3.1.11 (+8 more)	3.1.12
Microsoft.NETCore.App.Runtime.android-x86	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3
Microsoft.NETCore.App.Runtime.Mono.LLVM.AOT.linux-x64	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3
Microsoft.NETCore.App.Host.osx-x64	nuget	3.1.0, 3.1.1, 3.1.10, 3.1.11 (+8 more)	3.1.12
Microsoft.NETCore.App.Runtime.linux-x64	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3
Microsoft.NETCore.App.Runtime.Mono.LLVM.linux-arm64	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3
Microsoft.NETCore.App.Runtime.win-arm	nuget	3.1.0, 3.1.1, 3.1.10, 3.1.11 (+8 more)	3.1.12
Microsoft.NETCore.App.Runtime.Mono.linux-musl-x64	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3
Microsoft.NETCore.App.Runtime.win-arm	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3
Microsoft.NETCore.App.Runtime.rhel.6-x64	nuget	3.1.0, 3.1.1, 3.1.10, 3.1.11 (+8 more)	3.1.12
Microsoft.NETCore.App.Host.win-arm	nuget	3.1.0, 3.1.1, 3.1.10, 3.1.11 (+8 more)	3.1.12
Microsoft.NETCore.App.Runtime.win-x64	nuget	3.1.0, 3.1.1, 3.1.10, 3.1.11 (+8 more)	3.1.12
Microsoft.NETCore.App.Host.linux-x64	nuget	3.1.0, 3.1.1, 3.1.10, 3.1.11 (+8 more)	3.1.12
Microsoft.NETCore.App.Runtime.ios-arm	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3
Microsoft.NETCore.App.Host.win-arm64	nuget	3.1.0, 3.1.1, 3.1.10, 3.1.11 (+8 more)	3.1.12
Microsoft.NETCore.App.Runtime.Mono.linux-arm	nuget	5.0.0, 5.0.1, 5.0.2	5.0.3

CVSS Score Breakdown

What the CVSS (Common Vulnerability Scoring System) 6.5 score means for each attack dimension.

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

References

Frequently Asked Questions

What is CVE-2021-1721?: Denial of service in .NET core This vulnerability has been assigned a severity rating of MEDIUM (CVSS score: 6.5/10).
How do I check if my project is affected by CVE-2021-1721?: CVE-2021-1721 affects Microsoft.NETCore.App.Runtime.Mono.LLVM.AOT.osx-x64, Microsoft.NETCore.App.Runtime.osx-x64 and Microsoft.NETCore.App.Runtime.android-arm (and 42 more). Use GeekWala's free vulnerability scanner to check your dependencies against CVE-2021-1721 and 200,000+ other known vulnerabilities.

Severity & Exploitability

CVSS Score

6.5

Exploitation requires specific conditions or has limited impact. Remediate within weeks.

Also Known As

GHSA-3gp9-h8hw-pxpw

BIT-dotnet-2021-1721

BIT-dotnet-sdk-2021-1721

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