Crack PDF password on Ubuntu

pdfI was looking for some tools to crack or remove PDF passwords from an encrypted PDF file today. I googled for sometime and came across some native tools on Ubuntu as well as online websites which can be of help.

To start with, a brief on PDF passwords:

  • User password – doesn’t let you view the file.
  • Owner password – you can view the file but cannot print, copy contents etc.

The tools and site I found useful are:

  • PDFCrack: uses a brute force approach to find the passwords. Quite flexible. Available in the default repos. To install on Ubuntu:
    $ sudo apt-get install pdfcrack
  • PDFtk: lets you create a decrypted version of the file if you provide the password. Available in synaptic. To install on Ubuntu:
    $ sudo apt-get install pdftk
  • Witwall – similar functionality as PDFtk, but online. No need to install anything.

RarCrack: recover passwords for rar, 7z & zip

cool_penguin_smallForgetting passwords of your encrypted files is common. Here’s an open source solution for an attempt to recover the passwords using brute-force approach.

A similar utility to specifically crack zip file passwords is FCrackZip. It is written in Assembly and is fast. It uses brute-force as well as dictionary based attack. It can optionally unzip the files to verify the results.

Webpage: RarCrack!FCrackZip

Beware of privacy while registering for a domain

cool_penguin_smallGetting your own domain is exciting; a private web space to enjoy and show-off. But beware of inadvertently exposing personal information like address, mobile number, email etc. when you are registering for a domain as an individual and not as a registered company. A simple whois lookup can reveal all your information to complete strangers. Check this:

$ whois couponact.com
...
...
...
Registrant:
Prashanth kondakalla
# 4-1-102 Attapur
Hyderabad, Andhra Pradesh 500030
India

Registered through: GoDaddy.com, LLC (http://www.godaddy.com)
Domain Name: COUPONACT.COM
Created on: 28-Aug-11
Expires on: 28-Aug-13
Last Updated on: 23-Jan-12
Administrative Contact:
kondakalla, Prashanth  kpr@rws.in
# 4-1-102 Attapur
Hyderabad, Andhra Pradesh 500030
India
+91-994-986-9612

Technical Contact:
kondakalla, Prashanth  kpr@rws.in
# 4-1-102 Attapur
Hyderabad, Andhra Pradesh 500030
India
+91-994-986-9612
Domain servers in listed order:
NS1.CLICKWINKS.COM
NS2.CLICKWINKS.COM