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I would like to know, if renewing a SSL certificate will change my thumbprint? The certificate has expired.

If it can be same then under what conditions can it remain same.

Many thanks in advance.

Godwin
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2 Answers2

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It depends on what fingerprint you mean.

  • The public key fingerprint is a hash of the public key only. Since the public key stays the same on a simple renewing, this fingerprint will be the same too.
  • The certificate fingerprint as shown in the browser is instead a hash of the complete certificate. Since the contents of the certificate will change to reflect the new start and expiration time, this fingerprint will change too.
Steffen Ullrich
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Fingerprint for Public Key Pinning stays the same if you renew the cert with the same private key you used before. See this page for instructions how to generate the fingerprint, you can see it can be extracted from private key or CSR, not only from the cert itself.

zakjan
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