‘cURL error 60 SSL certificate problem’ occurs when we make a cURL call to third party services.

Here at Bobcares, we have seen several such cURL command related errors as part of our Server Management Services for web hosts and online service providers.

Today we’ll take a look at the causes for this error and see the fix.

What causes ‘cURL error 60 SSL certificate problem’ error to occur

Digital certificates are mainly used in transferring sensitive content. These digital certificates are issued by certificate authorities or CA.

When a cURL receives a server CA that is not signed by one of the trusted certificates in the installed CA certificate store, then it will lead to an error: “failed to verify the legitimacy of the server” during the SSL handshake. As a result, SSL will then refuse the communication with the server leading to an SSL error.

In short, this error occurs because cURL makes sure to verify and make a secure connection request using a self-signed certificate. But when it doesn’t find any valid certificate then it throws this error message.

How we fix the error ‘cURL error 60 SSL certificate problem’

Now let’s see how our Support Engineers resolve this error message.

1. Re-download the cURL CA-Bundle from the cURL site to fix this error. Here are the steps for it.

• First, download the “cacert.pem” from the link: http://curl.haxx.se/docs/caextract.html
• Next copy the complete page and save it as “cacert.pem”
• Now, open the php.ini file and add the following line in it.
  curl.cainfo = “[pathtofile]cacert.pem”
  In, case, if the php.ini file doesn’t have the curl.cainfo line, then just add it to the end of the file. Then add the file path where cacert.pem file is saved.
• Finally, restart the web server or on Windows, restart the application pool and try the request again.

2. If the insecure certificate is a self-signed, known-trusted certificate, then load the certificate to your local trusted certificate location for your OS.

[Need any further assistance in fixing curl errors? – We are here to help you.]

Conclusion

In short, this error occurs when cURL doesn’t find any valid certificate to communicate over https. Today, we saw how our Support Engineers fix this error.