I just installed an SSL certificate from Let's Encrypt on one of my domains. Everything was fine, green lock icon on Chrome. But just to be sure, I checked the domain on ssllabs.com. And to my surprise, It has the worst rating, an F. It seems that my server is vulnerable to OpenSSL CCS vulnerability (CVE-2014-0224).
My servers runs Ubuntu 14.04. I tried to update the packages and install a new version of OpenSSL, but I couldn't find any so I built it from source. But now that I have the latest version, I don't see any difference when I check the domain on SSLLabs, it is still rated F.
What should I do to fix this vulnerability once and for all ?
Thanks.