
If you want to crack pdf file passwords use pdfcrack.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).
pdfcrack Features
Supports the standard security handler (revision 2 and 3) on all known PDF-versions
Supports cracking both owner and userpasswords
Both wordlists and bruteforcing the password is supported
Simple...