MVC4 AntiForgery token cookie name is appended with random string - asp.net-mvc-4

Question

I am encountering an issue with MVC4's
#Html.AntiForgeryToken()
html helper. On my development machine, when I run the project, upon inspecting the headers (using Fiddler) , the name of the token returned is
__RequestVerificationToken
But when deployed to an IIS version 7.5 (Windows 2008 R2), then token name looks like:
__RequestVerificationToken_L2V6b3JkZXI1
Where is this getting changed? Is it because my application is not deployed to the "root folder" of the IIS? E.g. my application is deployed to
"http://myserver/myapp" instead of "http://myserver"

Answer 1

I found the answer after looking at the source code:
http://aspnetwebstack.codeplex.com/SourceControl/latest#src/System.Web.WebPages/Helpers/AntiForgeryConfig.cs
Yes, because my application was deployed to a path, the following code below appends the encoded equivalent of the path... Hope this finding will save you trouble.
// If the app path is provided, we're generating a cookie name rather than a field name, and the cookie names should
// be unique so that a development server cookie and an IIS cookie - both running on localhost - don't stomp on
// each other.
internal static string GetAntiForgeryCookieName(string appPath)
{
if (String.IsNullOrEmpty(appPath) || appPath == "/")
{
return AntiForgeryTokenFieldName;
}
else
{
return AntiForgeryTokenFieldName + "_" + HttpServerUtility.UrlTokenEncode(Encoding.UTF8.GetBytes(appPath));
}
}

Answer 2

Resolution to this problem is very easy by the use of AntiForgeryConfig class.See the reference below.
https://learn.microsoft.com/en-us/dotnet/api/system.web.helpers.antiforgeryconfig?view=aspnet-webpages-3.2
Namespace:System.Web.Helpers
You need to add below code under Application_Start() event of Global.asax file.
if (AntiForgeryConfig.CookieName.Contains("__RequestVerificationToken"))
{
AntiForgeryConfig.CookieName = "__RequestVerificationToken";
}