Yudu Offline Reader Hack

  • Top 10 PDF cracks
  • DRM restriction removal
  • How to hack 'protected' PDF

Top 10 ways to unlock secure, protected PDF files, such as college eBooks, for easy offline viewing on mobile devices. Convert images to PDF, and more.

By default the downloadable offline version can be accessed in the toolbar as shown below: To link directly to the offline version (the downloadable zip file) we simply need to add /flash/resources/.shortname.zip to the end of the URL, where shortname is the name given in the Settings - General tab of your publication as shown below: The. Yes, you can download your Yuzu eTextbook offline by downloading the Android, iOS, Windows, or Mac app from their respective app store. Visit Yuzu.com to download the apps. Then sign in with your bookstore account and click the title to download. If you need assistance, contact Yuzu Customer Care at customercare@yuzu.com or 1-844-YUZUNOW (1-844.

YUDU Reader Walkthrough. The YUDU Reader interface has been designed to appear as simplistic and sleek as possible but hide a number of great tools and features that the reader can make use of. Here we go through a few of the options on the toolbar to ensure you are fully up to date with the offering of the YUDU Reader. Navigation Bar - Using. Thus, the IPC laid the foundation of secularism.It was widely appreciated as a state-of-the-art code and was, indeed, the first codification of criminal law in the British Empire.How significant it is?Today, it is the longest serving criminal code in the common-law world. The passcode, set by default on credit card machines since 1990, is easily found with a quick Google searach and has been exposed for so long there's no sense in trying to hide it.

What are PDF Files?

Yudu Offline Reader Hack

According to Wikipedia, the Portable Document Format (PDF) format is a subset of the PostScript format that concentrates on layouts and graphics, including compression, encryption, and embedded fonts. This makes sense having read somewhere that there is usually no problem with renaming .pdf files to .ps and treating them as PostScript for programs and scripts that operate on those types of files. Furthermore, one could surmise that renaming .ps files to .pdf is probably a bad idea because .ps files may contain additional capabilities not found in the PDF specifications. Adobe graciously allows royalty-free hacking of their patented PDF format by lowly software developers like us.

Why Cracking is Necessary

If somebody creates a PDF and then forgets the password, they need some way to recover the lost password.

Some school or company eBooks can not be opened or viewed without an active Internet connection to unlock content. This presents a problem for students and professionals who travel, or are otherwise not always online.

Once unlocked, some PDFs can be viewed offline, but only from within Adobe Reader, and only if they reside in the same folder in which they were decrypted. This presents problems for readers who don't like Adobe, and those who use removable drives or habitually organize their folders.

The remote host required by the protected PDF plugin will not be there forever. Hence, remotely-locked and protected PDF files will eventually quit working. They are like books that must be returned to the library. If they were purchased they should be converted into a plain, unencrypted format ASAP!

Once opened, most remotely-locked and protected PDFs allow printing. A clever person might try printing to a PostScript file, but the resulting PostScript file is still protected against ps2pdf converting it back to PDF.

ps2pdf output.ps
This PostScript file was created from an encrypted PDF file.
Redistilling encrypted PDF is not permitted.

Why Cracking is Not Necessary

This information is provided for personal, professional, and educational use only! The companies involved have released newer software, so we can read these documents on our devices without resorting to hacks. Illegally distributing Copyrighted material is illegal in most parts of the world. Depending on the locale, there could be additional penalties for cracking PDF passwords, or removing digital rights management (DRM) restrictions in connection with distribtion. We assert our basic human rights, including the right to customize material that we created, bargained for, or purchased. We expect to be able to modify our digital assets for our own uses, such as for offline presentation on other devices. We also expect to be able to gift, donate, loan, and even re-sell our dog-eared eBooks to friends as one would anything else, such as 'books.' That said, even asserting ones own digital rights these days could lead one into trouble. Many companies and schools have policies against using their computers for resource-intensive tasks such as cracking passwords. If there are any questions seek professional legal counsel.

Why Use Free and Open Source Tools?

Most PDF unlocker programs found on the Internet today are proprietary. That is they are programs for which no source code can be viewed. It is not good practice to go around downloading and running proprietary software. These programs could contain anything. Just because they pass a virus scan, or cost a lot, does not mean they are safe. New viruses, bugs, and backdoors are made all the time. At least with open source there are many eyes presumably reviewing the code. The mere presence of source code does not guarantee absolute safety. Therefore, the best security practice is to review and compile the code for oneself, or rely on a trusted software distribution center, or distro, to review and compile the code and provide signed binaries for download.

PDF Encryption

Our research indicates that there are at least three broad, general types of protections for PDF files.

  • User password - Password required to decrypt and open PDF file
  • Owner password - Security signatures prevent copying, etc...
  • 3rd party JS - Content unlocked via the Internet.

PDF unlocker programs found on the Internet today only deal with user password and owner passwords. None of these programs deal with PDF files that encrypt the content using 3rd party plug-ins (but we can remove the plugins using free and open source tools, provided that we can use the password first to unlock and permit the plugin to download the secret content).

PDF files with 3rd party plug-ins have a login page on page 1, where the viewer enters their username and password. The remaining pages appear blank until they are unlocked.

3rd party plug-ins employ JavaScript (JS) on the password page to send the password or certificate to a 3rd party server. This requires an active Internet connection. If the computer is offline, Adobe Reader will respond with a not-so-friendly 'unknown error' and can't open the PDF. Once connected and the unlock request finally gets through, the 3rd party server verifies the login and either responds with the actual content, or exchanges a certificate to unlock the file contents for viewing. From that point on, Adobe's reader may prevent access if the file has been copied to another device, or even to another location on the same PC. Additional JS may track the file whenever and wherever it is opened, reporting potential Copyright violations.

Usually a document that uses 3rd party JS is also restricted using one or more of the following security signatures as well.

Security Signatures

Yudu offline reader hack download

According to PDF Rights Management, Adobe's questionable implementation of Digital rights management (DRM) controls and security signatures started with allowing the creation of documents with any of the following restrictions:

  • printing
  • modification
  • copying
  • adding / changing comments or form fields

Later PDF restriction possibilities were refined to include restricting assembly, extraction for accessibility, commenting, filling in form fields, signing, or template creation. Starting with PDF 1.5 these permissions are managed by usage rights (UR) signatures (Wikipedia).

Now on to the hacks.

Hack Number 1

Tools: Web Browser, Bookshelf
Target: All

Students using the popular Bookshelf online ebook viewer web page can print copies using 'print frame' or 'save frame' techniques. Bookshelf's print button may say something like, 'printing of this title is restricted to two pages at a time,' with restrictions set by publisher. Simply open the book in Bookshelf's online viewer, right-click on the frame containing the book or chapter, choose 'this frame', and either 'print frame', or 'save frame'. Voila! All pages are printed or saved. This is confirmed to work on Firefox and Chrome web browsers, printing, or saving to any of HTML, PostScript, or PDF formats.

Not using Bookshelf? Find an unencrypted copy of the ebook viewable or downloadable online. With so many file sharing sites, ebook readers, and search engines out there, one can find earlier versions, or unencrypted copies of just about anything free or cheap. Dig through Google Books, Amazon, Pastebin, Bearshare, Pirate Bay, The Dark Web. Gopher. FTP it. Usenet still exists...

Caution: Proprietary Viewers. The installable Bookshelf app (not to be confused with the Bookshelf web page we just used) purports to download ebooks for offline viewing on Windows, iOS, OSX, Android, and Kindle. This requires purchase and activation of Bookshelf app on up to two machines. It is doubtful that the resulting downloads can be copied or shared as they would remain encrypted and controlled within the Bookshelf downloads folder where they can spy on users and report on their whereabouts when opened. Bookshelf apps appear to be proprietary and not recommended.

Hack Number 2

Tools: Adobe Reader, qpdf and Ghostscript's ps2pdf
Target: 3rd party JS, content restrictions.

This method entails first downloading the PDF ebook, and running qpdf on the download using the --qdf option to normalize and uncompress the data. Once normalized and uncompressed, the PDF may be unlocked from within Adobe Reader and printed to file. The resulting PostScript file is unprotected and may be freely redistilled (converted) back to PDF with Ghostscript's ps2pdf. Presto. No more 'Redistilling encrypted PDF is not permitted' message!

qpdf --qdf input.pdf output.pdf
acroread output.pdf # unlock, print-to-file output.ps
ps2pdf output.ps # output.pdf is now unlocked

Hack Number 3

Tools: Adobe Reader, sed, and Ghostscript's ps2pdf
Target: 3rd party JS, content restrictions.

This method entails using Adobe Reader to unlock the file via the Internet in the usual way and then print to file. The resulting PostScript file is protected and has to be hacked with sed before it can be redistilled (converted) back to PDF with Ghostscript's ps2pdf. The conversion process runs very slowly because of PostScript errors introduced from the sed hack, but it is good for small chapters when technique #1 does not work, or when qpdf can not be installed on the system.

acroread output.pdf # unlock, print-to-file output.ps
sed '/mark currentfile eexec/,/cleartomark/ d' output.ps |
ps2pdf - output.pdf

Hack Number 4

Tools: pdfcrack
Target: password-protected PDF
Bonus: Free and Open Source
Drawback: Not for 3rd party JS

If somebody creates a PDF and then loses the password, they can recover the password with the pdfcrack command line password recovery tool. The tool leverages a brute force attack against the PDF password until it opens. The attack proceeds offline and nothing is exchaned via the Internet. Owner passwords can be found with the -o switch. Password cracking of longer passwords can take days or weeks to crack, so we limit the password length to 9 characters. This hack can not and does not work over the Internet with content locked by a 3rd party JS plugin. How could it? It would have to hack into the 3rd party server to do that!

pdfcrack -n 9 input.pdf

Hack Number 5

Tools: Google Drive
Target: password-protected PDF
Drawbacks: 2Mb file size, Not for 3rd party JS

Upload the owner password protected PDF to Google Drive. Google will convert the PDF for viewing online. Google Drive limits uploads to 2Mb.

Hack Number 6

Tools: Foxit Reader, CutePDF
Target: 3rd party JS, content restrictions
Drawbacks: Proprietary software. Relies on bugs.

Download Foxit Reader and CutePDF Writer. Unlocked PDF files can currently be printed to PDF from within Foxit Reader by selecting the CutePDF device from the list of available printers. This hole may become patched in later versions.

Hack Number 7

Tools: Adobe Reader, Microsoft XPS Viewer, CutePDF
Target: 3rd party JS, content restrictions
Drawbacks: Proprietary software. Relies on bugs.

Install Microsoft XPS Document Writer. Open the protected PDF in Adobe Reader reader. Print the file choosing the Microsoft XPS Document Writer from the list of available printers. Use XPS Viewer to open the resulting XPS file. Now print to PDF using CutePDF. This hole may become patched in later versions.

Hack Number 8

Tools: Ghostscript, GSView
Target: content restrictions

Install Ghostscript and GSView. Change the extension of the PDF file to .ps and open with GSView. If .ps file can be opened and viewed, it can be saved as a PDF file. Resulting PDF is free of restrictions, including restrictions on printing.

Hack Number 9

Tools: Web browser
Target: password-protected PDF

Visit the PDF Unlocker web site. Select the PDF file to unlock and let it upload to the server. Click the Download button to obtain the unlocked PDF file.

Hack Number 10

Tools: Web browser
Target: password-protected PDF

Yudu Offline Reader Hack Pc

Drawbacks: Proprietary software. Not for 3rd party JS
Hack

Various 'unlocker' programs exist on the Internet. Search for PDF password recovery. Proprietary software alert. Caveat emptor (buyer beware). These programs do not really unlock 3rd party JS plugins. Some demos available online even spend a minute conducting a fake test that pretends to open the file. They say the PDF can be unlocked, but then, after purchase, these programs unlock file passwords only. They do not actually work against 3rd party JS server passwords. How could they? They would have to hack the server to do that. While server hacking is certainly possible, it is beyond the scope of this howto.

Summary

Many of these techniques involve opening a PDF file from within Adobe Reader, allowing JavaScript to unlock it, and then printing it to file. There are many ways to print to PostScript or PDF, and literally hundreds of ways to break the restrictions on the resulting files. Earlier methods that no longer work include using Ghostscript to convert the PDF (or PostScript) file to earlier versions of PostScript, and then back to PDF. Those earlier PostScript drivers have been deprecated, but older versions of Ghostscript still provide them.

Convert to PDF When All Else Fails

Yudu offline reader hack free
Tools: Web browser
Target: content restrictions

Some PDFs won't allow printing or saving, and some of them are timed access. If it can be viewed, it can be screen captured. Simply open it up, preferably on a large desktop that can be tilted to where it shows the whole page, and take a screenshot of each page. It might be a good idea to empty out the screenshots folder first! Hopefully this will create a series of numbered images there. Then use something like imagemagick to convert the series of numbered images into a PDF file. The result might be great, or not so pretty depending on the desktop resolution, page dimensions, and other factors. The document can not be text searched because it is composed out of images, but there are programs that can optically recognize the text, and create a searchable index for PDF files. Hope this helps!

Links

Adobe Reader
Foxit Reader
CutePDF
pdfcrack command line password recovery tool
How to Unlock a Secure PDF File
PDF Rights Management
Portable Document Format

Copyright © 2020 Henry Kroll III, thenerdshow.com This web page is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License.

UpdatedBarnes and Noble tonight confirmed it was hacked, and that its customers' personal information may have been accessed by the intruders. The cyber-break-in forced the bookseller to take its systems offline this week to clean up the mess. See our update at the end of this piece. Our original report follows.

Bookseller Barnes and Noble’s computer network fell over this week, and its IT staff are having to restore servers from backups.

The effects of the collapse were first felt on Sunday, with owners of B&N's Nook tablets discovering they were unable to download their purchased e-books to their gadgets nor buy new ones. That is to say, if they had bought an e-book and hadn't downloaded it to their device before B&N's cloud imploded, they would be unable to open and read the digital tome. The bookseller's Android and Windows 10 apps were similarly affected.

It soon became clear the problem was quite serious when some cash registers in Barnes and Noble’s physical stores also briefly stopped working.

One Register reader told us that as a result of the downtime:

You can see all of your purchases on your Nook, but you can't download any of them if you haven't already. This includes purchases you might have made during the outage. When you try, you see an error: 'Internal error: Exception executing the command.' This is consistent, whether it is the app for Android phones, the app for Windows 10, or Nook devices themselves.

In other words, none of the books you've bought from today back to the day you signed up for a Nook account are available for you to download and read.

When you go to your account on the Nook website, your library is empty. 100 per cent empty – and there is usually a free thing or two in there when you first sign up, but now it's nothing. In some cases, the cover images of books etc don't download. In some cases, you can't use the online store, either.

B&N has yet to confirm any details of the ongoing network collapse – which has spanned at least three days now – though it is whispered that malware may have taken hold of the bookseller's machines and spread to stores and the Nook cloud. The company told The Register it has “a network issue and are in the process of restoring our server backups,” which sounds like a ransomware attack.

The book flogger also said it is “investigating the cause,” though stressed there has been “no compromise of customer payment details which are encrypted and tokenized.”

This weekend you better read those ebooks you bought from Microsoft – because they'll be dead come early July

READ MORE

That feels like a carefully worded statement and leaves open the possibility other customer records may have been compromised or meddled with – such as usernames, passwords, and contact details – but that payment information was protected.

Pressed for more detail on whether malware was responsible or whether user data had been compromised, a Barnes & Noble representative noted only that it was “working urgently to get Nook repaired,' and was investigating.

The length of time that the network has been down and the lack of communication from the company points to a more serious problem than a simple network failure. Initially the biz said the system would be back up within a few hours of the first reports of problems.

Partial restore

On Tuesday, some parts of the network reappeared, with cash registers and the BN.com website largely back up on Wednesday, although some webpages still showed problems and the Nook e-book system has been up and down all day, and at the time of writing is still suffering problems.

It wasn’t until Wednesday afternoon that a notice finally appeared on the Nook site announcing: “We're very sorry - NOOK Books are currently unavailable due to a system issue. We'll have this fixed as soon as we can.”

Yudu Offline Reader Hack Download

The Nook twitter account also finally acknowledged the problem mid-morning on Wednesday: “We are continuing to experience a systems failure that is interrupting NOOK content. We are working urgently to get all NOOK services back to full operation. Unfortunately it has taken longer than anticipated, and we sincerely apologize for this inconvenience and frustration,” it tweeted.

A second tweet continued: “Please be assured that there is no compromise of customer payment details which are encrypted and tokenized. We expect NOOK to be fully operational shortly and will post an update once systems are restored. Thank you for your patience.” ®

Updated to add

Shortly after this article was published, Barnes & Noble confirmed in an email to customers that it was hacked. The biz said it found out over the weekend, on October 10, that miscreants had broken into its computer systems, adding that customers' personal information stored on file may have been accessed or taken by the intruders. This info includes names, addresses, telephone numbers, and purchase histories.

Here are the salient portions of the message sent out this evening:

It is with the greatest regret we inform you that we were made aware on October 10, 2020 that Barnes & Noble had been the victim of a cybersecurity attack, which resulted in unauthorized and unlawful access to certain Barnes & Noble corporate systems.

Yudu Offline Reader Hack Free

Firstly, to reassure you, there has been no compromise of payment card or other such financial data. These are encrypted and tokenized and not accessible. The systems impacted, however, did contain your email address and, if supplied by you, your billing and shipping address and telephone number. We currently have no evidence of the exposure of any of this data, but we cannot at this stage rule out the possibility. We give below answers to some frequently asked questions.

Your payment details have not been exposed. Barnes & Noble uses technology that encrypts all credit cards and at no time is there any unencrypted payment information in any Barnes & Noble system. No financial information was accessible. It is always encrypted and tokenized. It is possible that your email address was exposed and, as a result, you may receive unsolicited emails.

While we do not know if any personal information was exposed as a result of the attack, we do retain in the impacted systems your billing and shipping addresses, your email address and your telephone number if you have supplied these. We also retain your transaction history, meaning purchase information related to the books and other products that you have bought from us.

We'll update this story again as more information arrives.

Yudu Offline Reader Hack Tool

Get ourTech Resources