[okular] [Bug 461371] PDFs digitally signed with Okular become locked in Adobe Acrobat so no one else can sign it

[Nicolas Fella]

https://bugs.kde.org/show_bug.cgi?id=461371

Nicolas Fella <nicolas.fella at gmx.de> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |nicolas.fella at gmx.de

--- Comment #2 from Nicolas Fella <nicolas.fella at gmx.de> ---
PDF allows for some fine-grained control about what you can do with a signed
document and what not

Looking at https://www.verypdf.com/document/pdf-format-reference/pg_0733.htm I
see this:

The access permissions granted for this document. Valid values are:
1 No changes to the document are permitted; any change to the document
invalidates the signature
2 Permitted changes are filling in forms, instantiating page templates, and
signing; other changes invalidate the signature.
3 Permitted changes are the same as for 2, as well as annotation creation,
deletion, and modification; other changes invalidate the signature

Default value: 2

Okular/Poppler doesn't set this, so the default (2) applies. That should
explain why you cannot add a new signature (which is technically similar to
adding an annotation). You should be able to do the things described in 2, like
filling in forms.

Note that this is my understanding based on reading the linked site and the
poppler source, I haven't reproduced the issue to confirm yet

-- 
You are receiving this mail because:
You are the assignee for the bug.