Insecure password warning in Firefox for ASDL Modem Login
I have a ASDL modem and every time I go to the login screen I see a lock icon on the left side of the address bar with a red slash or line through it. When I click on it a small drop down window appears telling me "18.104.22.168 - Connection is not secure - Logins entered on this page could be compromised". Why is it telling me this? Am I not secure to log in to my own modem? Am I being hacked or redirected? It did not used to show this in the past, so this is a new issue, I have logged on to this modem in the past and never got this message.
I checked out CenturyLink Modem : nothing to worry about.
Click on the little black arrow, next to that 'Connection is not secure' message. Then click on 'Learn More' , and you'll see what this is all about. You will not be sharing any personal information on that page. When you go to 'My Account', and check that 'i' in the circle again (or the padlock, same effect), you'll see that now you get the 'Secure Connection' message.
Data you enter on HTTP pages is not protected from interception because there is no encryption on HTTP connections: your username and password are sent out over the network as plain text. The slashed lock started appearing in this situation in Firefox 51.
This is by contrast to what happens on pages with HTTPS addresses and a green lock icon: Firefox and the server agree on long encryption keys that scramble your submissions. Anyone intercepting that communication gets unreadable gibberish.
Now... since you are only sending your login a few feet/meters, this may not be a major concern. Firefox doesn't know whether there is an intruder in your network intercepting the local traffic, you would need to rely on other tools to check for that.