Advisories for Nuget/Microsoft.Owin package

Microsoft is releasing this security advisory to provide information about a vulnerability in .NET 6.0, .NET 5.0 and .NET Core 3.1. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability. A vulnerability exists in .NET 6.0, .NET 5.0 and .NET core 3.1 where a malicious client can manipulate cookies and cause a Denial of Service.

A security feature bypass vulnerability exists in the way Microsoft ASP.NET Core parses encoded cookie names. The ASP.NET Core cookie parser decodes entire cookie strings which could allow a malicious attacker to set a second cookie with the name being percent encoded. The security update addresses the vulnerability by fixing the way the ASP.NET Core cookie parser handles encoded names., aka 'Microsoft ASP.NET Core Security Feature Bypass Vulnerability'.