pdfcrack software package provides PDF files password cracker, you can install in your Ubuntu 14.04 LTS (Trusty Tahr) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install pdfcrack
pdfcrack is installed in your system.
Make ensure the pdfcrack package were installed using the commands given below,
$ sudo dpkg-query -l | grep pdfcrack *
You will get with pdfcrack package name, version, architecture and description in a table
| Distro | Ubuntu 14 04 lts trusty tahr |
| Section | Utilities |
| Package | pdfcrack |
| Version | 0.12-1 |
| Description | PDF files password cracker |
| Sub Section | Utils |