> Sometimes you want to send out a finalized document and want to make 99% of the users unable to edit them. That's what PDFs are for. Imagine lawyers needing t

> Sometimes you want to send out a finalized document and want to make 99% of the users unable to edit them. That's what PDFs are for. Imagine lawyers needing to send out a finalized contract. That is not what PDFs are for. PDF is, well, a Portable Document Format. It is not convenient to modify a PDF, but PDF is not securely resistant to modification (discounting its cryptographic features [0]). Its resistance to modification is a side-effect of its design, not a primary goal. An attacker will be able to modify your PDF. This gets easier every year, as we'd expect. That doesn't matter, though, as an attacker can always recreate the document, with whichever changes they wish. (Again, neither of these attacks will work if you use cryptographic signing.) If you want secure assurance of authenticity, you use cryptographic signing. No excuses. If you're a lawyer, I'd hope you aren't placing any stock at all in the inconvenience of modifying a PDF. [0] https://acrobat.adobe.com/uk/en/sign/capabilities/digital-signatures-faq.html https://acrobat.adobe.com/uk/en/sign/capabilities/digital-si...