From AutoValidateAntiforgeryTokenAttribute documentation:
An attribute that causes validation of antiforgery tokens for all
unsafe HTTP methods. An antiforgery token is required for HTTP methods
other than GET, HEAD, OPTIONS, and TRACE. It can be applied at as a
global filter to trigger validation of antiforgery tokens by default
for an application.
AutoValidateAntiforgeryTokenAttribute allows to apply Anti-forgery token validation globally to all unsafe methods e.g. POST, PUT, PATCH and DELETE. Thus you don’t need to add [ValidateAntiForgeryToken] attribute to each and every action that requires it.
To use it add the following code to your ConfigureServices method of Startup class
services.AddMvc(options =>
{
options.Filters.Add(new AutoValidateAntiforgeryTokenAttribute());
});
If you need to ignore Anti forgery validation you can add [IgnoreAntiforgeryToken] attribute to the action.