Using ASP.NET Server Controls in MVC?

On my current project I need to add a functionality that allows the user to view a thumbnail of their uploaded PDF. I’ve found a handy component that achieves this (the basic version is free, but it’s enough for my current needs). Anyways, the control is pretty outdated (2010), therefore there doesn’t seem to be MVC support. On the demos they depict usage of the control as such:

Reference to type ‘HttpContextBase’ claims it is defined in ‘System.Web’ but it could not be found

I’m getting a really weird error that I’ve only found a few times with some pretty extensive googling. I’m making an authorization attribute to add onto my Actions in an ASP.NET MVC project in a class library. I installed the ASP packages through NuGet and can use intellisense to get the HttpContext from the filterContext, but it’s saying that the HttpContext type can’t be found where it’s supposed to be.