PDF Crack is a tool for recovering the pass for Encrypted PDF files. Encrypted files means the metadata of the file was encrypted with some characters.
It has some special features like:
- Checks with the system password and also the user provided password.
- It can crack password by brute-forcing method only for character sets and only when we provide the maximum and minimum length of the password.
- Searches the password from the wordlist.
- Optimized search for owner-password when user-password is known.
To install PDF Crack,
$ sudo apt-get install pdfcrack
The general usage of pdfcrack for brute-forcing is,
$ pdfcrack -f <file_name>
The genearal usage of pdfcrack when we provided a wordlist is,
$ pdfcrack -f <file_name> -w <location_of_wordlist_file>
Here is an example, using a wordlist. On opening the PDF, we found that the file was protected.
We used dictionary attack(using a wordlist) to find the password.
In this way cracking the password of PDF files is done when you don't know/forget the password.
If you unfortunately, click ctrl+c then it will save the process until you clicked into an another file called savedstate.sav in the directory where the PDF is present or the current directory.
For further reference visit,
$ man pdfcrack