PDFCrack is a GNU/Linux (other POSIX-compatible systems should work too) tool for recovering passwords and content from PDF-files. It is small, command line driven without external dependencies. The application is Open Source (GPL).
I compiled it under Windows, but it is a console version, maybe some body like a GUI for it, but I am not familiar with GUI creation.
for detail,
We don't support Linux at this time. We've been told that in the future it might be a possiblity but right now it's just an idea. Part of the problem is that the language that we use to right our launchers (NSIS) does not support Linux. We don't actually edit the programs. We simply write a launcher that moves things to the HDD from the thumbdrive on start and then move them back on exit, along with some more complicated stuff, but that's the basic idea. Sorry about that, but welcome to PortableApps.com :).
Release Team Member
He said it compiles under windows too, he'd just like a GUI for it...
The developer formerly known as ZGitRDun8705
He mentioned he's compiled it for Windows, and thought somebody might be interested in trying to create a GUI for it, which might actually not be all that hard considering there's a few users that've already done a couple GUI's in Auto Hot Key.