GuaPDF for Linux 2.3

The primary goal of GuaPDF is to
remove restrictions on any PDF document (you should have the right to do it, for example, if you forgot the password). Any Acrobat version up to 8 is supported, even with 128-bit AES or RC4 encryption. PDF permission password removal is an instant process. Decrypted file can be opened in any PDF viewer without any restrictions so you may edit/copy/print it.

GuaPDF can be also used for
remove the PDF open password. Decryption of the file with password for opening is guaranteed for PDF files with 40-bit key only (Acrobat 3, 4 compatible encryption). This process takes several days on one home computer.

Only standard PDF security is supported, neither third-party plug-ins nor e-books.

Features
GuaPDF is the unique software with full support of Acrobat 7, 8 files (including compressed files and AES encryption).
Advantages of GuaPDF are:
Guarantee of decryption
Newest PDF 1.7 (Acrobat 8.x) files support, including AES encryption, compressed files and unencrypted metadata
Very high speed (optimized for Pentium II/III, Pentium 4, Core 2 and AMD architecture)
Confidentiality (you crack your secret files, not someone from cracking service)
Versions for single processor, dual/dual-core processor and network version to use power of distributed clients
Portability (DOS, Windows, Linux, Solaris, Mac OS versions are available)
Running in GUI and keeps running in batch mode (as command-line utility)