title: How is a private key encrypted in a pem certificate?
body: <p>As part of trying to debug an issue, I am trying to understand how a private key is encrypted in a <code>pem</code> certificate, because I am wondering whether <code>curl</code> does not manage to decrypt the private key.</p>
  <p>I have a <code>-----BEGIN ENCRYPTED PRIVATE KEY-----</code> section in my <code>pem</code>.</p>
  <p>Is it encrypted with the passphrase? Is there some other kind of encryption scheme involved?</p>
  <p><strong>More precisely</strong></p>
  <p>A colleague suggests a private key could be encrypted in a <code>pem</code> even without a passphrase. Is this correct?</p>