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 permutations (currently only trying first character as Upper Case) Save/Load a running job Simple benchmarking Optimised search for owner-password when user-password is known Install pdfcrack in Ubuntu sudo aptitude install pdfcrack pdfcrack Syntax pdfcrack -f filename [options] pdfcrack Options -b, - -bench - Perform benchmark and exit. -c, - -charset=STRING - Use the characters in STRING as charset. -m, - -maxpw=INTEGER - Stop when reaching INTEGER as password length. -n, - -minpw=INTEGER - Skip trying passwords sho...