Let’s Encrypt certificate expired on older Macs

I have a number of older machines that I use on a regular basis, so I’m no stranger to the struggles of not being able to browse current websites on older machines with older browsers and the typical SSL/TLS support issues that you run into. I was surprised to see this error this week on my 2008 Mac Pro running Mac OS X 10.11 El Capitan and a latest version of Chrome:

Looking at the certificate for any site not loading it looks like the certificate has expired:

I’m not seeing this on my other later/current machines though, so clearly something on these older machines is no longer getting updates. Browsing around a few other sites and seeing the same issue on many sites so it was not just limited to a single site, so I realized something else was going on. Some Googling found this article:

Following the steps to download the updated certificate from LetsEncrypt and install it into Keychain did the job.

nginx ssl cert error:

When you concatenated your SSL .crt intermediate and root certs together, it’s likely you ended up with lines line this:

—–END CERTIFICATE———-BEGIN CERTIFICATE—–

To fix this, manually edit to insert a newline between the end and begin like this, and you should be all set:

-----END CERTIFICATE-----
-----BEGIN CERTIFICATE-----

New WoSign/StartCom certificates issued after Jan 1st 2017 blocked on Apple products

My first 1 year free SSL certificate with StartSSL is about to expire this month, so time to renew for another year. At this point last year I wasn’t sure what would happen at this point 1 year later, but appears you just apply for another new certificate, and then replace it on the servers where you are using it.

 

However, once I had requested my new certificate and uploaded it to my OpenShift account, Chrome blocked access to my site with a ‘certificate revoked’ error. I bit of digging turned up this article. Due to a number of security related issues with the Certificate Authority WoSign and later their undisclosed purchase of StartCom/StartSSL, it appears use of certificates from either of these companies are now blocked on all Apple products if issued after Jan 1st 2017, and also on Firefox and Chrome too. More info on Wikipedia here, and Mozilla here and here.