Chapter 1 What’s New for FortiOS 5.0 : New features in FortiOS 5.0 Patch 3 : URL Filtering
  
URL Filtering
URL filtering has changed to allow certificate-based URL filtering for HTTPS traffic, which is used when deep-scan is disabled.
Certificate-based filtering extracts the hostname from the TLS handshake. If a valid hostname is found, it is used for the local or FortiGuard category query. If no hostname is found, HTTPS server CN web filtering will be used instead.