CVE-2026-102870: ASP.NET Core Remote Code Execution Vulnerability

Severity: high (CVSS 8.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.9% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-10-13 · updated 2026-10-31
Weakness: CWE-94

Description

Improper control of generation of code ('code injection') in ASP.NET Core allows an unauthorized attacker to execute code over a network.

Affected products

Microsoft .NET 10.0 installed on Linux: from 10.0.0 before 10.0.403 — fixed in 10.0.403
Microsoft .NET 10.0 installed on Mac OS: from 10.0.0 before 10.0.403 — fixed in 10.0.403
Microsoft .NET 10.0 installed on Windows: from 10.0.0 before 10.0.403 — fixed in 10.0.403
Microsoft .NET 11.0 installed on Linux: from 11.0.0-preview.1 before 11.0.100-rc.3 — fixed in 11.0.100-rc.3
Microsoft .NET 11.0 installed on Mac OS: from 11.0.0-preview.1 before 11.0.100-rc.3 — fixed in 11.0.100-rc.3
Microsoft .NET 11.0 installed on Windows: from 11.0.0-preview.1 before 11.0.100-rc.3 — fixed in 11.0.100-rc.3
Microsoft.AspNetCore.Components.WebAssembly.DevServer: from 11.0.0-preview.1 before 10.0.14 — fixed in 10.0.14
Microsoft.AspNetCore.Components.WebAssembly.Server: from 10.0.0 before 10.0.13 — fixed in 10.0.13
Microsoft Visual Studio 2019 version 16.11: from 16.11.0 before 16.11.61 — fixed in 16.11.61
Microsoft Visual Studio 2026 version 18.10: from 18.10.0 before 18.10.4 — fixed in 18.10.4
Microsoft Visual Studio 2026 version 18.11: from 18.11.0 before 18.11.2 — fixed in 18.11.2
Microsoft Visual Studio 2026 version 18.12: from 18.12.0 before 18.12 Insiders 3 — fixed in 18.12 Insiders 3
Microsoft Visual Studio 2022 version 17.14: from 17.14.0 before 17.14.43 — fixed in 17.14.43

How to fix

Upgrade to a fixed version: Microsoft .NET 10.0 installed on Linux 10.0.403; Microsoft .NET 10.0 installed on Mac OS 10.0.403; Microsoft .NET 10.0 installed on Windows 10.0.403; Microsoft .NET 11.0 installed on Linux 11.0.100-rc.3; Microsoft .NET 11.0 installed on Mac OS 11.0.100-rc.3; Microsoft .NET 11.0 installed on Windows 11.0.100-rc.3; Microsoft.AspNetCore.Components.WebAssembly.DevServer 10.0.14; Microsoft.AspNetCore.Components.WebAssembly.Server 10.0.13; Microsoft Visual Studio 2019 version 16.11 16.11.61; Microsoft Visual Studio 2026 version 18.10 18.10.4; Microsoft Visual Studio 2026 version 18.11 18.11.2; Microsoft Visual Studio 2026 version 18.12 18.12 Insiders 3. Check the vendor advisory for mitigations.

In the news

CVE-2026-102870 ASP.NET Core Remote Code Execution Vulnerability

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-102870

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