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  1. PDFBox
  2. PDFBOX-3848

Get the exact original PDF that was signed(without signature fields)

    Details

    • Type: Bug
    • Status: Closed
    • Priority: Major
    • Resolution: Not A Problem
    • Affects Version/s: 2.0.6
    • Fix Version/s: None
    • Component/s: AcroForm, Signing
    • Labels:
      None

      Description

      I am trying to get the original pdf from the signed pdf.

      I am able to remove the signature using doc.getSignatureDictionaries().get(0).getSignedContent(signedPDF);

      However, the signature field stays.

      However, when I try to remove the signature fields using the following code:

      PDDocument pdDoc = PDDocument.load(origPDF);
      PDDocumentCatalog catalog = pdDoc.getDocumentCatalog();
      PDAcroForm form = catalog.getAcroForm();
      List<PDField> acroFormFields = form.getFields();
      for (PDField field: acroFormFields) {
      if (field.getFieldType().equalsIgnoreCase("Sig"))

      { System.out.println("START removing Sign Flags"); field.setReadOnly(true); field.setRequired(false); field.setNoExport(true); System.out.println("END removing Sign Flags"); System.out.println("START flattenning field"); field.getAcroForm().flatten(); field.getAcroForm().refreshAppearances(); System.out.println("END flattenning field"); //field.getAcroForm().refreshAppearances(); }

      The signature field is removed, but the image that was used for visible signature, somehow, magically appear. (The document that I load here is the one that has signature removed using origPDF = doc.getSignatureDictionaries().get(0).getSignedContent(signedPDF);

      See the attached files:
      Example.pdf (Original file)
      Example_Signed.pdf (Signed File)
      Example_Signed_orig.pdf (after removing the signature)
      Example_Signed_final.pdf (after flattening the Example_Signed_orig.pdf)

      See the stackoverflow post for more details:

      https://stackoverflow.com/questions/44843095/verifying-pdf-signature-in-java-using-bouncy-castle-and-pdfbox

        Attachments

        1. Example.pdf
          11 kB
          Nikola Radosevic
        2. Example_Signed.pdf
          36 kB
          Nikola Radosevic
        3. Example_signed_orig.pdf
          21 kB
          Nikola Radosevic
        4. Example_signed_final.pdf
          20 kB
          Nikola Radosevic

          Activity

            People

            • Assignee:
              Unassigned
              Reporter:
              nikola.radosevic Nikola Radosevic
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              Dates

              • Created:
                Updated:
                Resolved: