PDF Password Cracker Professional edition allows to search for "owner" and "user" passwords with brute-force and dictionary attacks, effectively optimized for speed (however, don't expect to recover long passwords in a reasonable time with these attacks). In addition, it has Key search attack, which guarantees the decryption (regardless the password length and complexity) of PDF files that use 40-bit encryption (the attack takes about 3-4 days on fast CPU systems).

The standard security provided by PDF consists of two different methods and two different passwords. Owner Password allows to prevent PDF file from printing, editing (changing), selecting text and graphics (and copying them into the Clipboard), or adding/changing annotations and form fields; User Password locks the file so the password is required to open or view the file. If only owner password is set, decryption is being done instantly; decrypted file can be opened in any PDF viewer (e.g. Adobe Acrobat Reader) without any restrictions, i.e. with edit/copy/print/annotate functions enabled. Alternatively, owner password can be recovered using brute-force or dictionary attacks.

Additionally, PDF Password Cracker Pro supports "key search" attack that allows to decrypt (in a reasonable time) PDF files with 40-bit security regardless the password length, guaranteed.

Key Features of PDF Password Cracker Pro
- Easy to use
- Drag and drop PDF files
- Do NOT need Adobe Acrobat software
- Support Windows 98, ME, NT, 2000, XP, 2003, Vista Systems
- Support PDF 1.7 (Acrobat 8.x) files, including 40-bit RC4 decryption, 128-bit RC4 decryption, AES decryption, compressed files and unencrypted metadata
- Support Adobe Standard 40-bit decryption, Adobe Advanced 128-bit decryption and AES decryption
- Recovers user password required to open the file
- Brute-Force, or Dictionary attacks are used to recover the password
- Additional user dictionaries support, case changes, multiple mistypes and other modifications for each dictionary word
- Program automatically saves password search state and can resume after a stop or a crash
- Patterns can be used to minimize search time if any part of the password is known
- Non-English characters in passwords are supported

How to use the PDF Password Cracker Pro product?
- Open the PDF Password Cracker Pro program by either going to Programs, select PDF Password Cracker Pro v3.0 and click PDF Password Cracker Pro v3.0. The interface below will display.
- Click the "Load" button to locate the file which you would like to remove the passwords, then click the "Open" button.
- Click the "Decrypt" button or "Start" button, then PDF Password Cracker Pro will test the passwords for your PDF file automatically.
- Once PDF Password Cracker Pro retrieved the user password, it will popup a "Save As" dialog, you may save to a normal PDF file directly, all restrictions will be removed from this decrypted PDF file.

Known limitations
PDF files protected using PDF Merchant and EBX digital rights management schemes or 3rd party plugins such as FileOpen, SoftLock etc cannot be decrypted.
Brute-force attack is effective for short passwords only, usually up to 7-8 chars. Recovering longer ones will take too much time (months, years) even on a very fast computer. If your file has "user" password and use 40-bit encryption, you can use Key search attack.