Home / ubuntu / Questions / 1110174
Accepted
RedM
Asked: 2019-01-16 23:19:06 +0800 CST

How do I digitally sign PDFs in 2019?

  • 772

This older post is either pointing to mostly dead software or the answers are not fully applicable.

I want to take a PDF document, stick in an image of my signature and have this be digitally signed using a certificate so that the document is secured and any changes will be picked up.

I'd like to open a document, navigate to the relevant signature page, click on the line or draw a box, enter a password and my signature should be drawn and certificate used to digitally sign the doc.

I've tried the following options and here are the problems:

  • Libre Office: Difficult to sign existing PDF's, better to create pdf's with. Have to add signature image separately.

  • PortableSigner: Hard to position signature but does the job

  • Master PDF Editor: Works well but takes 70 dollars to prevent ugly watermark being added to PDF's

  • Foxit Reader: Only adds image without any certificate signing.

Any ideas?

encryption pdf libreoffice open-source

7 Answers

  1. I use DocuSign, which is free web app (for single signatures). It also serves as a (hopefully) trusted third party.

    From DocuSign - Wikipedia:

    DocuSign, Inc. is an American company headquartered in San Francisco, California that allows organizations to manage electronic agreements. As part of the DocuSign Agreement Cloud, DocuSign offers eSignature, a way to sign electronically on different devices. DocuSign claims it has over 475,000 customers and hundreds of millions of users in more than 180 countries. Signatures processed by DocuSign are compliant with the US ESIGN Act. and the European Union's eIDAS regulation, including EU Advanced and EU Qualified Signatures.

    • 2

  2. Here's how to add a picture into an existing PDF file.

    I would sign the pdf with GNU Privacy Guard (GPG). There is a list of frontends, I use GNU Privacy Assistant (GPA, apt install gpa). It works pretty well.

    • 2

  3. I recommend you go through the list of OpenSC based applications. OpenSC is the base library of most applications using smartcard and USB key hardware certificates.

    At first glance, the following seem interesting for your use case (though I haven't tried them myself yet):

    • 1
  4. Best Answer

    You may also want to take a look at the Simple Signer. In addition to LibreOffice Draw, it can also add a visual stamp onto the document (which is linked to your signature) as known from the Adobe Reader.

    In addition to that, you can choose if you want to sign or certify your document.

    • 1

  5. You create in LibreOffice your usual document as new document (*.doc or *.odt) - when document is created finish, then add watermark like it is described here :

    https://libreofficehelp.com/how-to-add-watermark-in-libreoffice-writer/

    When watermark is set finish, you then can export this document to format PDF.

    • 0

  6. I'd like to open a document, navigate to the relevant signature page, click on the line or draw a box, enter a password and my signature should be drawn and certificate used to digitally sign the doc.

    Web based Online interactive Digital Signing solution available for free use, which can sign interactively by drawing rectangle. Digital Certificate can be picked from client's USB Token or Smartcard on Linux clients and is available at https://web.signer.digital

    If you are developer, the components (browser extension, again free to use) may also be integrated with any server side pdf library in your web applications.

    • 0

  7. You need a (free) adobe.com account, but you can upload your PDFs to https://documentcloud.adobe.com and use their 'Fill & Sign' tool. Probably a bit clumsy if you have a lot of PDFs to manage, but it's a quick route to getting the job done for infrequent PDF users like me.

    • 0