CVE-2026-50526: Microsoft Security Advisory CVE-2026-50526 – .NET Tampering Vulnerability

July 21, 2026

Microsoft is releasing this security advisory to provide information about a vulnerability in .NET SDK (Microsoft.NET.Build.Containers). This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability.

A tampering vulnerability exists in the .NET SDK (.NET 8, .NET 9, and .NET 10) container image build process which could allow a local attacker to inject resources that could be incorporated into container images built by other users on the same machine.

References

github.com/advisories/GHSA-55jh-fwmh-39m4
github.com/dotnet/announcements/issues/415
github.com/dotnet/sdk/issues/55274
github.com/dotnet/sdk/security/advisories/GHSA-55jh-fwmh-39m4
msrc.microsoft.com/update-guide/vulnerability/CVE-2026-50526
nvd.nist.gov/vuln/detail/CVE-2026-50526

Code Behaviors & Features

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