PDF Password Cracker Enterprise 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).

PDF security overview
The standard security provided by PDF consists of two different methods and two different passwords. A PDF document may be protected by password for opening ('user' password) and the document may also specify operations that should be restricted even when the document is decrypted: printing; copying text and graphics out of the document; modifying the document; and adding or modifying text notes and AcroForm fields (using 'owner' password).

Key Features
bullet New PDF 1.7 (Acrobat 8.x) files support, including 64bit and 128bit RC4 decryption
bullet Support AES decryption
bullet Confidentiality (you crack your secret files, not someone from cracking service)
bullet All versions through Adobe Acrobat 8.0 are supported
bullet Decrypt PDF files protected with owner passwords
bullet Instantly remove restrictions on copying, printing and other actions with the file
bullet Full install/uninstall support
bullet Support drag and drop PDF files
bullet Do NOT need Adobe Acrobat software
bullet Support Windows 98, ME, NT, 2000, XP, 2003, Vista systems
bullet Support PDF1.7 (Acrobat 8.x) files, including 40-bit RC4 decryption, 128-bit RC4 decryption and AES decryption
bullet Decryption, compressed files and unencrypted metadata
bullet Decrypt protected Adobe Acrobat PDF files, removing restrictions on printing, editing, copying

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