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PDF files password cracker
pdfcrack is a simple tool for recovering passwords from pdf-documents.
It should be able to handle all pdfs that uses the standard security handler
but the pdf-parsing routines are a bit of a quick hack so you might stumble
across some pdfs where the parser needs to be fixed to handle.

pdfcrack allows configure the size of the searched password, use an
external wordlist file and save cracking sessions to restore it later.

Homepage: http://sourceforge.net/projects/pdfcrack