I've encountered a strange thing. I connected to an open Wi-Fi, then I was just fooling around. First, I visited 192.168.0.1 and it was a router configuration page but default password didn't work.
Then I navigated to 192.186.1.1 and I saw the configurator of a completely different router that isn't even on this network. The SSID is different, and it's also encrypted with WPA2-PSK. The default username and pasword (admin/admin) worked.
How come I managed to connect to it? How can I notify the owner? Is it illegal?
Here's a screenshot:

