Cross-site scripting (XSS) vulnerability in ASP.NET in Microsoft .NET Framework 4, 4.5, 4.5.1, 4.5.2, and 4.6 allows remote attackers to inject arbitrary web script or HTML via a crafted value, aka ".NET Elevation of Privilege Vulnerability."
The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.