curl server certificate verification failed

Question

I have a bunch of PHP scripts that use curl to communicate with various services. Currently, one of those services' SSL certificate got updated and my curl started crying about it when I try to get it from my server's CLI:

~$ curl https://example.com

curl: (60) server certificate verification failed. CAfile: /etc/ssl/certs/ca-certificates.crt CRLfile: none
More details here: http://curl.haxx.se/docs/sslcerts.html

curl performs SSL certificate verification by default, using a "bundle" of Certificate Authority (CA) public keys (CA certs). If the default bundle file isn't adequate, you can specify an alternate file using the --cacert option.
If this HTTPS server uses a certificate signed by a CA represented in the bundle, the certificate verification probably failed due to a problem with the certificate (it might be expired, or the name might not match the domain name in the URL).

If you'd like to turn off curl's verification of the certificate, use the -k (or --insecure) option.

Currently, I hardcoded verify => false to all of my requests in order to keep my scripts operating but that's not something I would like to have laying around.

I got the latest cacert file from mozilla, put it in /etc/ssl/certs/ca-certificates.crt and then ran sudo update-ca-certificates which ran successfully (I suppose..)

~$ sudo update-ca-certificates
Updating certificates in /etc/ssl/certs...
0 added, 0 removed; done.
Running hooks in /etc/ca-certificates/update.d...
done.

But then again curl is not too happy about it, still can't get my resource without passing the -k flag.

Answer 1

You can use the openssl s_client command to further debug the issue, in order to find out what exactly seems to be the problem with the certificate.

openssl s_client -showcerts -servername myservice.com -connect myservice.com:443