Web User Interface
V7 came in with v 7.1.33: Advanced - QoS/Security (Tab) - Security(Section)__Use hidden security tags
V8: Advanced - QoS/Security (Tab) - Security(Section)__Use hidden security tags
Phone User Interface
You can protect the phone's web interface with hidden security tags against remote attackers trying to change phone settings with faked HTTP POST requests (XSRF attack).
This feature works only if you have changed HTTP User and Password as well as the Administrator Password from the default value!