ASP.NET Core Denial of Service Vulnerability

Publicly Disclosed:No;Exploited:No;Latest Software Release:Exploitation Less Likely CVE-2026-109478 · score 7.5/10

What could go wrong?

An attacker could make a program or service crash or stop responding.

How urgent is it?

Check Microsoft’s page for details.

Who is affected?

.NET 9.0 installed on Linux, .NET 9.0 installed on Mac OS, .NET 9.0 installed on Windows, .NET 8.0 installed on Windows, .NET 8.0 installed on Linux, .NET 8.0 installed on Mac OS, Microsoft Visual Studio 2022 version 17.14, Microsoft Visual Studio 2026 version 18.11 and 1 more versions

What should I do?

Install this month’s updates via Windows Update, Intune or your update tool, then restart.

Known problems

Microsoft lists known issues per update: KB5135243. Official page.