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Originally Posted by CommanderROR
1) does it work on your device?
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No. It needs Reader 7.0 to be read, and Reader for Pocket PC 2.0 is not up to that level. If you want portability, you better use 40-bit encryption.
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2) could you remove the "owner information" and how easy was it?
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Didn't even try. However ... as the document reads perfectly without password (once I fire up Reader 7.0), I doubt that it would be a serious problem.
Reader can clearly decrypt the information on it's own, and display it. When I try to do something that's not in the rights field (P), it's Reader, not the PDF file that implements the protection.
So I simply get my own reader (say, xpdf -- haven't checked if it does 1.5 decryption, though), remove the test for 'is this forbidden by DRM', if there is one, recompile it, run, open the file, save the file without encryption or compression, fire up a text editor, and remove the lines you've added manually. (There used to be a PostScript file around that could be used in GhostView that did much the same thing ... pdf_sec.ps. Don't know if it can be made to work for AES encryption) Once the PDF reader (or equivalent) decides to ignore the DRM specification in the file, you can do almost anything.
However ... once you require the user to enter a password before the document can be read, you get better protection. Then the password guessing and cryptanalysis starts in earnest.
I'm not entirely sure, but it may be possible simply to delete the
page the added text is on -- much rougher, but equally effective.
There's no security without passwords or equivalents: there's just obfuscation.