Curl OpenSSL error 141A318A tls_process_ske_dhe:dh key too small

The usual recommendation for this error is to set the "CipherString" parameter in /etc/ssl/openssl.cnf to "DEFAULT:@SECLEVEL=1".

• https://askubuntu.com/a/1233456
• https://imlc.me/dh-key-too-small

In PHP, you can achieve the same thing with curl_setopt():

curl_setopt($ch, CURLOPT_SSL_CIPHER_LIST, 'DEFAULT@SECLEVEL=1');

This is a better solution than editing openssl.cnf since it allows you to relax security for just one specific call, rather than system-wide.

If you are using the file_get_contents() function, this works nicely

$context=array(
    "ssl"=>array(
        'ciphers' => 'DEFAULT:!DH'
    ),
); 

$json = file_get_contents($url, false, stream_context_create($context));