PDFCrack is a GNU/Linux application (or any other POSIX -compatible system) tool for recovering passwords and content from PDF -files. It is small, command line driven without external dependencies. PDFCrack is released under GPL .
Install and pdfcrack on Ubuntu by typing:
cc@zeus:~$ sudo aptitude install pdfcrack
Run a quick cracking power benchmark:
cc@zeus:~/Desktop$ pdfcrack -b
Benchmark: Average Speed (calls / second):
MD5: 1728972.6
MD5_50 (fast): 97879.3
MD5_50 (slow): 69167.0
RC4 (40, static): 606555.3
RC4 (40, no check): 598050.0
RC4 (128, no check): 590141.7
Benchmark: Average Speed (passwords / second):
PDF (40, user): 453510.2
PDF (40, owner): 220250.0
PDF (40, owner, fast): 499995.0
PDF (128, user): 22000.0
PDF (128, owner): 10408.7
PDF (128, owner, fast): 22220.0
cc@zeus:~/Desktop$
Use the pdfcrack to crack an encrypted pdf-file by typing:
cc@zeus:~/Desktop$ pdfcrack test.pdf
Happy pdf-hacking and cracking