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javapdfboxdigital-signature

What is the significance of the certificate in a PDF document signed using PDFBox?

How can I interpret the left icon in the first signature of a signed PDF document using PDFBox 3? The right icon is displaying correctly in the second signature, but I am unsure about the meaning of the left icon.

Here is a screenshot for reference:

screenshot

Solution

  • For Acrobat 9.0 Adobe had this cheat sheet for the meaning of the symbols in the signature panel:

    Acrobat Signature Validation Cheat Sheet

    The exact appearance of those symbols changed a bit over time but the Certifié icon can be recognized as

    Certified entry of table

    Thus, just like the second signature in your example it is a successfully verified signature. In contrast, though, it is a "certification" (aka "author") signature while the other is an "approval" signature.

    PDFBox creates certification signatures as first signatures only if you ask it to. E.g. the signing example code for that contains this code:

            // Optional: certify 
        if (accessPermissions == 0)
        {
            SigUtils.setMDPPermission(document, signature, 2);
        }

    If you don't want a certification signature, drop the SigUtils.setMDPPermission call.