Improper access control in Microsoft products - CVE-2026-50528

Vulnerability identifier: #VU138081

CSH Severity: Medium

CVSS v4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-50528

CWE-ID: CWE-284

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to bypass the authentication feature.

The vulnerability exists due to improper access control in .NET authentication handling when processing network requests. A remote attacker can send crafted requests to bypass the authentication feature.

The issue can result in impersonation.

.NET for macOS
.NET for Linux
Visual Studio
.NET
Red Hat CodeReady Linux Builder for IBM z Systems - Extended Update Support
Red Hat CodeReady Linux Builder for ARM 64 - Extended Update Support
Red Hat CodeReady Linux Builder for Power, little endian - Extended Update Support
Red Hat CodeReady Linux Builder for x86_64 - Extended Update Support
Red Hat Enterprise Linux for ARM 64 - Extended Update Support
Red Hat Enterprise Linux for Power, little endian - Extended Update Support
Red Hat Enterprise Linux for IBM z Systems - Extended Update Support
Red Hat Enterprise Linux for x86_64 - Extended Update Support
Ubuntu
dotnet10 (Ubuntu package)
dotnet8.0 (Red Hat package)
dotnet9.0 (Red Hat package)

Install security update from vendor's website.

.NET for macOS - addressed in versions 8.0.29, 9.0.18
.NET - addressed in versions 8.0.29, 9.0.18
.NET for Linux - addressed in versions 8.0.29, 9.0.18
Visual Studio - update to 17.12.22
dotnet10 (Ubuntu package) - addressed in versions 8.0.29-0ubuntu1~22.04.1, 8.0.29-0ubuntu1~24.04.1, 8.0.129-0ubuntu1~22.04.1, 8.0.129-0ubuntu1~24.04.1, 8.0.129-8.0.29-0ubuntu1~22.04.1, 8.0.129-8.0.29-0ubuntu1~24.04.1, 10.0.10-0ubuntu1~24.04.1, 10.0.10-0ubuntu1~26.04.1, 10.0.110-0ubuntu1~24.04.1, 10.0.110-0ubuntu1~26.04.1, 10.0.110-10.0.10-0ubuntu1~24.04.1, 10.0.110-10.0.10-0ubuntu1~26.04.1
dotnet8.0 (Red Hat package) - update to 8.0.130-1.el10_0
dotnet9.0 (Red Hat package) - update to 9.0.120-1.el10_0

• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2026-50528

• Multiple vulnerabilities in Visual Studio
• Ubuntu update for dotnet10
• Red Hat Enterprise Linux 10 update for .NET 8.0
• Red Hat Enterprise Linux 10 update for .NET 9.0