|Summary:||Password required on document that opens without using Acrobat|
|Product:||poppler||Reporter:||Robinson Tryon (qubit) <qubit>|
|Status:||RESOLVED FIXED||QA Contact:|
|Priority:||high||CC:||arnaud.versini, m.weghorn, qubit|
|i915 platform:||i915 features:|
|Bug Depends on:|
Slides from LibreOffice2013 presentation
Slides from LibreOffice2013 presentation - cleaned with MuPDF
Description Robinson Tryon (qubit) 2013-10-20 21:16:21 UTC
Created attachment 87897 [details] Slides from LibreOffice2013 presentation Hi, LibreOffice is in the process of assembling slides from our last conference and one of our presenters gave us a PDF export [see attachment] of PowerPoint slides which opens in Adobe Acrobat on Windows without a password, but gives a "Password required" prompt on Evince 3.4.0 on Ubuntu 12.04.3. Testing with pdf2ps 9.05, gives the following error: " **** This file uses an unknown standard security handler revision: 6" ...which looks like this bug: http://bugs.ghostscript.com/show_bug.cgi?id=693305 (I stole the title from bug 3498, but I believe this is a separate issue :-)
Comment 1 Albert Astals Cid 2013-10-20 22:04:43 UTC
FWIW Adobe Acrobat on Linux doesn't open the file here either.
Comment 2 James Cloos 2013-10-21 05:06:36 UTC
Interesting. GhostScript also is unable to open it, but mupdf can do so. The mupdf src has this comment about /R 6: /* * Compute an encryption key (PDF 1.7 ExtensionLevel 8 algorithm) * * Adobe has not yet released the details, so the algorithm reference is: * http://esec-lab.sogeti.com/post/The-undocumented-password-validation-algorithm-of-Adobe-Reader-X */ That will be needed to handle this document. -JimC
Comment 3 Robinson Tryon (qubit) 2013-10-23 14:35:27 UTC
Created attachment 88038 [details] Slides from LibreOffice2013 presentation - cleaned with MuPDF (In reply to comment #2) > Interesting. > > GhostScript also is unable to open it, but mupdf can do so. Excellent. Looks like we can mupdf to convert the PDF files. WORKAROUND: Build MuPDF from source (3379bea "Remove duplicated line.") and use mutool to massage a (seemingly) encrypted PDF into something more standard. For example: qubit@loopbackoffice:~/src/mupdf/build/debug/mutool clean LibO\ Conf\ 2013\ as\ presented.pdf LibO-Conf-2013_cleaned-with-mupdf.pdf Evince can open the output PDF properly.
Comment 4 Michael Weghorn 2018-01-11 08:10:42 UTC
This is no longer reproducible since support has been added to poppler a while ago. This is also documented in the referenced LibreOffice bug report.