ColdFusion 10 has an inbuilt mechanism in the administrator for notification & installation of the updates as and when they are available. When you login to the ColdFusion administrator, you would see the notification for the updates that are available and you can install the update right from the administrator.
In case you want to download and install the updates manually, you can refer to the following article
http://blogs.coldfusion.com/post.cfm/how-to-download-and-install-coldf usion-10-hotfix-directly