Steam and related services use bad certificates

I can't use any of the steam services related to my steam account.

I get (as a for instance)

Unable to communicate securely with peer: requested domain name does not match the
server’s certificate.
HTTP Strict Transport Security: false
HTTP Public Key Pinning: false

I can still play CS:GO without problems. My steam client says Error -107 which is curiously devoid of Google hits.

How do I debug this?

Is this a problem on my end or theirs?

Firefox reports the error as

SSL_ERROR_BAD_CERT_DOMAIN

My steam client has now replaced the error -107 with

Invalid SSL Certificate

1 Answer

The solution I found to this problem was to enter steam web page on a computer that can access the web page, then export the certificates being used and later import them to the computer having the problem.