How to drop (rather than refuse) traffic on NetBIOS and other related ports?

How can I get a Turris Omnia to drop (rather than reject) traffic from the WAN to ports 135, 137, 138, 139 and 445 on the router, please?

By default, traffic from WAN to LAN is disabled (exclude honeypots). If you don’t enable it by redirecting in the firewall, just keep it quiet.

You can test opened port on youre extern IP (don’t worry opened honeypot ports) At the page bottom in the section ShieldsUP! https://www.grc.com/default.htm

I guess you want to skip messages about dropped packets to these ports (I know this on some servers).

You can insert custom firewall rules via luci in
“Network / Firewall/ Custom rules”

according to FW setup you can put the drop into chain input_rule or input_wan_rule.
I have tried to put custom rule into zone_wan_input but it got lost on reboot.