CVE-2024-21386: Microsoft Security Advisory CVE-2024-21386: .NET Denial of Service Vulnerability

February 13, 2024 (updated February 17, 2026)

Microsoft is releasing this security advisory to provide information about a vulnerability in ASP.NET 6.0, ASP.NET 7.0 and, ASP.NET 8.0 . This advisory also provides guidance on what developers can do to update their applications to address this vulnerability.

A vulnerability exists in ASP.NET applications using SignalR where a malicious client can result in a denial-of-service.

References

github.com/advisories/GHSA-g74q-5xw3-j7q9
github.com/dotnet/aspnetcore
github.com/dotnet/aspnetcore/security/advisories/GHSA-g74q-5xw3-j7q9
msrc.microsoft.com/update-guide/vulnerability/CVE-2024-21386
nvd.nist.gov/vuln/detail/CVE-2024-21386

Code Behaviors & Features

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