Netear LB1120 web management page inaccessible from different subnet

I have a new Netgear LB1120 modem with the latest firmware in router mode.  I can access its web page (192.168.2.70) just fine from the LAN if the source address is 192.168.2.x.  However, I cannot ping nor access its web page from a different subnet.  Note that this is the only device on the LAN that I cannot access from a different subnet so it is not a routing issue.  Traceroute confirms that the packets make it onto the 192.168.2.x LAN.

When I have seen this behaviour on other devices, there is usually some way to disable or pierce the device firewall to make it respond,

Note that I am not attempting remote management of the device from the WAN.  The problem is from the LAN side.