When I go to any github.com page in Chrome, I get a big ugly error:
You attempted to reach github.com, but the server presented a certificate issued by an entity that is not trusted by your computer's operating system. This may mean that the server has generated its own security credentials, which Chrome cannot rely on for identity information, or an attacker may be trying to intercept your communications.
You cannot proceed because the website operator has requested heightened security for this domain.
The same thing happens (in Chrome and with curl) when I go to https://www.digicert.com/ too. This strange problem started about a week and a half ago.
Here's what I see when I click the broken lock icon in the address bar:
But gist.github.com works just fine:
It doesn't work with curl either:
Everything works fine in Firefox.
How can I fix my root CA problem?
Here's what it looks like in Firefox:
Update:
I noticed that the first certificate in the chain is different in my broken Chrome/Safari as compared to Chrome on my other computer.
(There's no nasty red X anymore because I trusted it in Safari.) See how the issuers are different? What can I make of that?