List of blog entries

  • 2021-11-05 @Matthias Valvekens
    PDF Days Online 2021 talk: Cryptography in PDF: future perspectives

    Around the end of September, I shared some of my ideas on how we could iterate on PDF’s cryptographic feature set at the 2021 edition of the PDF Days, organised by the PDF Association. Originally, this event was scheduled to take place in Berlin, but it got moved online due to COVID-related concerns. I’ve embedded the video below.

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  • 2021-10-10 @Matthias Valvekens
    PDF As She Is Wrote #2: The quirks of PDF public-key encryption

    The previous instalment in this series had to do with digital signing in PDF. This post is about another, lesser known application of PKI in PDF: using PKI to encrypt PDF files. The idea is that this allows you to encrypt a PDF file with key material from one or more X.509 certificates, so that only the designated recipients can decrypt the document using their respective private keys.

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  • 2021-09-29 @Matthias Valvekens
    FOSDEM 2021 talk: Document security and digital signatures in PDF

    Last February, I gave a talk on PDF’s security features at FOSDEM ’21. The session was recorded, and is embedded below. This was my first talk at a non-maths conference; take that as you will.

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  • 2021-09-22 @Matthias Valvekens
    PDF As She Is Wrote #1: How are signers identified?

    This is the first installment in PDF as She Is Wrote . With this post, I intend to start a series on the way the PDF standards (mainly ISO 32000-x) are implemented in the “real world”. The focus is on implementation behaviour, not the minutiae of what the standard says (or should say), although I’ll occasionally comment on that as well. Given my area of interest, a significant portion of the content will relate to digital signing in some way.

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