Getting this warning when trying Cloudflare-dns.com from Chrome. Also it is flagged by our security software Untangle NGFW.
Cloudflare-dns.com normally uses encryption to protect your information. When Chromium tried to connect to (same URL, but had to remove or could not post) this time, the website sent back unusual and incorrect credentials. This may happen when an attacker is trying to pretend to be (ditto), or a Wi-Fi sign-in screen has interrupted the connection. Your information is still secure because Chromium stopped the connection before any data was exchanged.
You cannot visit (ditto) right now because the website uses HSTS. Network errors and attacks are usually temporary, so this page will probably work later.