Details
By default, the security appliance responds to incoming connection requests as either ‘blocked’ or ‘open.’ If you enable Stealth Mode, your security appliance does not respond to blocked inbound connection requests. Stealth Mode makes your security appliance essentially invisible to hackers.
Solution
Navigate to Firewall Settings->Advanced->Detection Prevention and check off ‘Enable Stealth Mode’.
This security hardening control applies to the following category of controls within NIST 800-53: System and Communications Protection.This control applies to the following type of system SonicWALL.