ASP.NET Core Information Disclosure Vulnerability

Publicly Disclosed:No;Exploited:No;Latest Software Release:Exploitation Less Likely CVE-2026-109476 · score 6.1/10

What could go wrong?

Private information could leak to someone who should not see it.

How urgent is it?

Check Microsoft’s page for details.

Who is affected?

.NET 8.0 installed on Windows, .NET 8.0 installed on Linux, .NET 8.0 installed on Mac OS, .NET 9.0 installed on Windows, .NET 9.0 installed on Linux, .NET 9.0 installed on Mac OS, .NET 10.0 installed on Windows, .NET 10.0 installed on Linux and 7 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, KB5135242, KB5135241. Official page.