Advanced eBook Processor (AEBPR)

Advanced eBook Processor, or simply AEBPR, is a program to decrypt eBooks in Acrobat eBook Reader format (PDF files with EBX security handler), as well as Adobe Acrobat PDF files protected using standard security method, WebBuy technology, or any other Acrobat security plug-in (like FileOpen, SoftLock etc) by converting them into plain PDF files – without any protection and restrictions. Decrypted file can be opened in any PDF viewer

(e.g. Adobe Acrobat Reader) with edit, copy, print, annotate functions enabled. All versions of Adobe Acrobat are supported. Can also decrypt eBook Pro (*.EBK) files, extracting all html pages and images from them.

Please note that unauthorised distribution of copyrighted materials is strictly prohibited. Please consult the license on PDF file or eBook you’ve purchased before processing it with AEBPR.

An eBook (electronic book) is simply a file that contains text and images – as in usual (printed) book, but with additional features such as hyperlinks (cross-references), searching capabilities and sometimes sounds/music. To read an eBook, you should have a PC with an appropriate software, or a special hardware device.

Most popular eBook formats are Adobe Acrobat PDF and Microsoft Reader .LIT. They are open-standard and cross-platform compatible. Open-standard means that it is not a proprietary (controlled by one person or company) digital file format. Nowadays, Acrobat .PDF's and Microsoft Reader.LIT's are quickly becoming the de-facto standard on the Internet for documents and previously published materials.

The software to view, print, and search an Acrobat .PDF file is free and available for over 14 different computer platforms (all versions of Windows; Mac, Unix, Linux etc) – this means that an eBook in the .PDF file format can be viewed on virtually any computer around the world.

For now, AEBPR doesn’t work with .LIT eBooks, and support .PDF and .EBK formats only.

One of the key features of all eBook formats is protection and security. The publisher can set security on a .PDF file to require a password just to open the file, and/or another password to block printing, changing, selecting text and graphics, and from changing any form field on the .PDF file. Specially for eBooks, some additional options have been added by Adobe.

PDF documents can be encrypted to protect their contents from unauthorized access. Access to a protected document's contents is controlled by the security handler. As already noted, PDF file may require a password just to open the file, and/or another password to block printing, changing, selecting text and graphics, and from changing any form field on the .PDF file. Please see the next chapter to learn what AEBPR can do with the documents protected with the standard security handler.

Adobe Content Server software makes it easy for you to sell electronic books (eBooks) securely online. Adobe Content Server packages and protects eBooks and distributes them in PDF format directly from any Web site. Anyone with the free Adobe Acrobat eBook Reader software can purchase your content with ease. That technology allows to enable or disable the following consumer permissions: copy text to clipboard, print all or a defined number of pages, lending, expiration, and text to speech. Adobe Content Server can encrypt eBooks in the Electronic Book Exchange (EBX) or Adobe PDF Merchant DRM (Digital Rights Management). When the file is encrypted, special master voucher for its distribution is being created. The master voucher is a separate, XML-based file that contains an encrypted key to the eBook and the set of privileges that accompany it. When a customer purchases an Adobe PDF eBook directly from an e-commerce site, it’s automatically downloaded into the customer’s personal Acrobat eBook Reader library for immediate viewing. Acrobat eBook Reader unlocks the encrypted key that came with the eBook and its master voucher. Now the eBook is tied to the customer’s Acrobat eBook Reader and can’t be transmitted elsewhere unless lending or gifting permission has been enabled.

Also, Adobe Acrobat provides a plug-in architecture to extend its functionality (actually, protection provided by Adobe Content Server described above is based on plug-in technology, too). Plug-ins can provide a rich and powerful addition to the core product, and give the capability to implement many new commands, and functions. There is are a special plug-ins called Security Handlers, that are responsible for a number of different functions. They set the access permissions for a file during a save, authorize access to a document when opening, setup and establish the key used for encryption and decryption. All security handlers are different, but AEBPR provides a generic method to break (decrypt) PDF files protected with ANY handler.

With a standard security handler, Adobe Acrobat features two levels of password protection.

Protecting document with access restriction (“owner”, also called “security” or “master”) password does not affect a user's ability to open and view the PDF file, but prevents user from editing (changing) the file, printing it, selecting text and graphics (and copying them into the Clipboard), adding/changing annotations and form fields etc (in any combination). If the file is protected this way, you open it in Adobe Acrobat Reader (again, the password is not required for that) and select File | Document Security menu item.

Fortunately, there is no need to recover that password at all: instead, we can remove it (decrypt the file), so the resulting document will not have any restrictions. However, such decryption possible only if “user” password (see below) is not set or known.

Also, there are “open” (so-called “user”) passwords. If one is set, the file is encrypted with strong RC4 algorithm, and cannot be opened at all, if the password is not known. You need to know this password to be able to decrypt the file protected this way.

Simply select the PDF file you want to decrypt: press the Open document... button and browse for your file. If the given file is corrupted, or used by another application, or not encrypted, or has a user-level password set – appropriate error message will be displayed (in the last case, you can still decrypt the file with AEBPR, but have to know either user or owner password). Otherwise, the program will prompt you for the file name of decrypted file (select any). Resulting file will not have any restrictions at all.

Please note that this (demo) version of AEBPR decrypts only first 10% pages (but at least one page) of protected documents. All other pages are replaced with blank ones (just some watermarks and hyperlinks are being left).

If Adobe Acrobat Reader doesn’t show the menu and/or toolbar (and so you don’t see the Print item), you can simply press F7 to show menu and F8 to show toolbar.

Web Buy is Adobe technology that lets you download encrypted files from the Web and unlock them to read on your personal computer or reading device. It is also a fully integrated component of Adobe Acrobat and Acrobat Reader (versions 4.05 and later). With Web Buy, you can purchase and view digital content that has been produced by publishers using Adobe PDF Merchant, a digital rights management technology incorporated in the Adobe Content Server.

In general, a PDF file is encrypted with a 56 or 128-bit access key that is generated from a 160-bit string that can either be provided by the user, or randomly generated internally. This 160-bit Title key is stored in the sellers’ database to uniquely identify each document. WebBuy attempts to first locate a license file contained either in the same folder as the PDF that is being opened, or in the users' license file repository. If a license file is not found, then WebBuy will prompt the user to "Go Online" and purchase a license for the book. If a license is found, then WebBuy will use this to generate the access key for PDF, and if successful, will provide this key to the decryption algorithm. After completing this step, WebBuy will signal to the Viewer that authorization is complete and that the file can be opened. At this stage, the eBook will open in the Adobe Acrobat viewer. Also, WebBuy supports the concept of superdistribution. That is, if a licensed PDF is sent to a friend who does not have a license, when the file is opened, the friend is prompted to "go-online" and to obtain a valid license from the seller. There are a few values that identify the patricular environment: computer identifier, user identifier, UTC time identifier, storage device identifier.

The publisher may specify a few permissions to WebBuy-locked PDF files: printing, changing the document, selecting text and graphics, adding or changing annotations and form fields, key length, weaknesses.

If you have a valid license to open a particular PDF file protected with WebBuy, i.e. if you’ve purchased that document from your computer and so have an appropriate license file (it should have the same name as PDF file, but RMF extension), or copied that file from computer PDF has been purchased from, AEBPR can decrypt it (again, decrypted file can be opened using any PDF viewer, without any additional plug-ins or license files). Just press “Open document...” button, select the file, and the program will prompt you for the name of decrypted file. If RMF file could not be found, you’ll get an appropriate error message.

There are a lot of 3rd party security plug-ins for Adobe Acrobat that allow to protect PDF documents. Various restrictions (from copy, print) can be set; also, the document may expire (i.e. you’ll be able to open it only till the given date). The most known are FileOpen, SoftLock and Internet Standards Australia.

If the file is protected using FileOpen or BPTE_rot13 plug-in, AEBPR decrypts it immediately, whether or not you have necessary permissions to open it.

For all other security plug-ins, AEBPR uses “generic” algorithm, which works the following way. It just executes Adobe Acrobat or Adobe Acrobat Reader (whichever program is installed on your computer and associated with PDF files; version 4.05 or later is needed); sends a command to open the given file; catches the decryption key (used by the Reader to open that file), and closes the Reader. Once the key is there, the document can be decrypted. It absolutely doesn’t matter how strong the encryption is, does the plug-in require some hardware dongle attached to the parallel port etc.

eBook Pro files (*.EBK) have their own format. From developer’s site:

When the end-user first registers the eBook software, they need to be connected to the Internet so that our servers can verify that their username and password are valid. After the registration is complete, the eBook has been designed to randomly (and automatically) check back with our servers to verify that the user' s code is still valid (i.e. marked "active"). If the user does not happen to be connected to the Internet when the eBook attempts to verify the registration, the eBook will wait until an Internet connection IS available. The eBook will then take this opportunity to verify the validity of the username and password. Because the eBook has already been registered, there will be no need for the end-user to enter their username or password again.

The reality: eBook Pro files are not secure at all. Even if you don’t have valid user name and password, AEBPR will decrypt and unpack the given EBK file, generating the source: HTML files, images etc. You just have to select the target folder all these files will be saved to.


Home page URL : http://www.elcomsoft.com/aebpr.html