MITM Attack on Gmail’s SSL in 2011


I have read these posts: https://www.cnet.com/news/fraudulent-google-certificate-points-to-internet-attack/

https://support.google.com/mail/forum/AAAAK7un8RU3J3r2JqFNTw/?hl=en&gpf=d/category-topic/gmail/share-and-discuss-with-others/3J3r2JqFNTw

As far as I know, a certificate should be installed on a server.

So I don’t quite understand how issuing a fraudulent certificate for *.google.com (the spelling of the common name is correct – it is not phishing) could trigger these browser warnings without installing it on a server.

I understand that a private key is in their hands but how did they manage to throw this certificate from the official Google website to users?

Did they install it on a Gmail server?

Could you explain, please?

Screenshot of certificate error in Chrome