Friday, July 2, 2010

I need your encrypted PDF files

I just released some major improvements to jsunpackn today in version 0.3.2c. The main new feature is the ability to parse encrypted PDF documents. One problem though, the output isn't quite perfect. For example, see one of these encrypted PDFs where jsunpackn extracted JavaScript:

Note, how certain characters in the output are not quite right, therefore the JavaScript decoding doesn't go beyond the first stage. If you find any PDF files with the string "/Encrypt" in them, please let me know, I'd like to test them to see if I can improve the parsing further. In the process of supporting the /Encrypt tag, I was able to build a testbed and was able to detect 20 new PDFs in my testcases with the new parsing!

I would like to thank Dave Touretzky (from the Computer Science Department and the Center for the Neural Basis of Cognition at Carnegie Mellon University) for posting details of encrypted PDFs within his Gallery of Adobe Remedies.