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Add signed hash to pdf as signature

Hi, we have a case & want to know if ASPOSE.PDF is capable to digitally signing a PDF document with a signed HASH of the document. Note the private key is not available for the certificate used to sign the document


At the moment, you can sign document and calculate its hash. But cannot store this value within document because it changes the hash. You may store hash value in separate file. An investigation ticket has already logged in our issue tracking system as PDFNET-48741. Would you please provide some more details about your requirement so that we may further proceed with investigation and share our feedback with you.

Please find below the requested:
1- We compute the Hash of document
2- Sending the computed hash to signing provider
3- Signing provider return the Signature Data ( Signed Hash )
4- We set signature data (Signed hash) to the Signature

We have tried another library “Syncfusion” to sign our documents and it is working fine, so we wanted to know if aspose has this capability or we need to procure another component. below is the sample code from the other library for your reference.

ComputeHash = Convert.FromBase64String(SignatureData);
Syncfusion.Pdf.Security.PdfSignature signature = new Syncfusion.Pdf.Security.PdfSignature(document, document.Pages[0], null, “DigitalSignature”);
signature.ComputeHash += Signature_ComputeHash;

    private static void Signature_ComputeHash(object sender, PdfSignatureEventArgs arguments)
        arguments.SignedData = ComputeHash;

Awaiting your feedback.


Thanks for sharing the requested information.

We have updated the earlier logged ticket accordingly and will investigate it as per provided information. We will let you know as soon as we have some definite updates regarding ticket resolution. Please be patient and spare us some time.