Do
you have a PDF (Adobe Acrobat) file which cannot be printed, copied, or
edited? Your PDF file has had password security and other restrictions
added.
First we will
try to crack a pdf in windows using the options below. Then if we get no
success we will use backtrack. You can install backtrack on windows.
Goto : http://www.piratedthief.tk/2012/09/set-up-your-very-own-hacking-lab-on.html
Windows:
1.Freemypdf.com
Freemypdf.com is a free website
that allows you to view restricted Pdf files.Use this site to remove
passwords and restrictions (such as printing, copying text, etc.) from
PDFs.
Note: This only works for PDF
FILE that you open and read without any Third party plugins. PDF file
that require a password to be viewed cannot be unlocked by this service.
This is because this is not
cracking. Viewable PDFs with restrictions are not really protected, no
more than a door with a broken lock, as opposed to password-protected
PDFs.
4. PDFCrack
www.pdfcrack.com
PDFCrack! is a free online PDF cracker. No installation, no registration, it's free and easy to use.
3.Crack My PDF
www.crackmypdf.com/
CrackMyPDF is a free online PDF unlocker. Unlock PDF file and remove restriction for editing, copying, printing and extracting with just few clicks.4.PDF Unlock Online Utility
www.ensode.net/pdf-crack.jsf
Backtrack:
You can install backtrack on windows .goto : http://anonymoussoft.blogspot.com/2012/10/set-up-your-very-own-hacking-lab-on.html
The tool to crack the password is called pdfcrack ( http://pdfcrack.sourceforge.net/ ).
It's a nifty little tool that cracks both user and owner passwords
applied to .pdf files. To download the tools, make sure you are root
(unless you are using BackTrack, in which case you already are), and
type in-
apt-get install pdfcrack
Now you are ready to crack your password-protected .pdf file. Just go to your Terminal and type-
pdfcrack
After you type in this command, you will see plenty of options-
root@bt:~# pdfcrack
Usage: pdfcrack -f filename [OPTIONS]
OPTIONS:
-b, --bench perform benchmark and exit
-c, --charset=STRING Use the characters in STRING as charset
-w, --wordlist=FILE Use FILE as source of passwords to try
-n, --minpw=INTEGER Skip trying passwords shorter than this
-m, --maxpw=INTEGER Stop when reaching this passwordlength
-l, --loadState=FILE Continue from the state saved in FILENAME
-o, --owner Work with the ownerpassword
-u, --user Work with the userpassword (default)
-p, --password=STRING Give userpassword to speed up breaking
ownerpassword (implies -o)
-q, --quiet Run quietly
-s, --permutate Try permutating the passwords (currently only
supports switching first character to uppercase)
-v, --version Print version and exit
For this guide, I will show you two
methods of cracking- a Dictionary Attack, and a Bruteforce Attack. The
first method we will use is a dictionary attack. This will read every
line of a wordlist until a match to the .pdf file's password is found. I
specified above that you should have used password as
your password for your .pdf file. Make sure you are in the same
directory as your password-protected .pdf file, then type this in your
Terminal-
pdfcrack -f [password-protected pdf file] --wordlist=[path to wordlist]
I named my .pdf file "crackme.pdf", so in BackTrack 5 my command would look like this-
pdfcrack -f crackme.pdf --wordlist=/pentest/passwords/wordlists/darkc0de.lst
Here is the output from my command-
root@bt:~/Hacking/Tutorials# pdfcrack -f crackme.pdf --wordlist=/pentest/passwords/wordlists/darkc0de.lst
PDF version 1.3
Security Handler: Standard
V: 2
R: 3
P: -3904
Length: 128
Encrypted Metadata: True
FileID: b1de5d9d3ca2f5ec1dc4514f2a583907
U: 1f10ccc1e8a59d7083f9bbc1acf9c70900000000000000000000000000000000
O: 43710afb9adf32376fad13575c2ae401b12dd0cd7b6cde9fca684132393c6604
Average Speed: 14601.4 w/s. Current Word: 'J Arthur Moore'
Average Speed: 14024.8 w/s. Current Word: 'avvizzimento'
Average Speed: 13901.1 w/s. Current Word: 'ferebamque'
Average Speed: 14160.5 w/s. Current Word: 'mescoleremo'
found user-password: 'password'
As you can see, pdfcrack cracked the password, specified by this line of output-
found user-password: 'password'
Yes, password was the password I chose.
The command for brute-forcing, however, will look like this-
pdfcrack -f crackme.pdf --charset=abcdefghijklmnopqrstuvwxyz -n 6
The
output for this command will be similar to the Dictionary Attack
output. However, this method will take longer, because it has to use the
character set (charset) we specified to find the password, instead of
using a dictionary file.
Remember brute force password cracking can take several days so it is our last option.
