python - NET::ERR_CERT_COMMON_NAME_INVALID - Error Message

Question

I built a website some time ago with Flask. Now all of a sudden when I try to navigate there I get the following:

NET::ERR_CERT_COMMON_NAME_INVALID

Your connection is not private Attackers might be trying to steal your information from www.mysite.org (for example, passwords, messages, or credit cards). Learn more

Does anyone know what's going on?

Answer 1

The certificate subject alternative name can be a domain name or IP address. If the certificate doesn’t have the correct subjectAlternativeName extension, users get a NET::ERR_CERT_COMMON_NAME_INVALID error letting them know that the connection isn’t private. If the certificate is missing a subjectAlternativeName extension, users see a warning in the Security panel in Chrome DevTools that lets them know the subject alternative name is missing.

https://support.google.com/chrome/a/answer/7391219?hl=en