HIGH 7.5 Microsoft

CVE-2026-42899

ASP.NET Core Denial of Service Vulnerability

Microsoft Security Update 2026-May: ASP.NET Core Denial of Service Vulnerability

Affected Products

.NET 8.0 installed on Windows
.NET 9.0 installed on Linux
.NET 8.0 installed on Mac OS
.NET 8.0 installed on Linux
.NET 9.0 installed on Windows
.NET 9.0 installed on Mac OS
.NET 10.0 installed on Mac OS
.NET 10.0 installed on Linux

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-42899
https://nvd.nist.gov/vuln/detail/CVE-2026-42899

Published: 2026-05-12 · Source: Microsoft · Feed updated: 2026-08-04

This high severity vulnerability with a CVSS score of 7.5 was published on 2026-05-12 via Microsoft. Affected: .NET 8.0 installed on Windows, .NET 9.0 installed on Linux, .NET 8.0 installed on Mac OS and 5 more.

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