Bryan, We had a new ASA and Firesight installed a couple weeks ago and we see the exact same thing. Its reporting https://s3-us-west-1.amazonaws.com as web application Ultrasurf. 

I'm running into this same issue on 10.5.2.10-15. Also, this is my first time dealing with CUAC and the system was set up before I started here, so any guidance would be appreciated.