Thanks Tilman Hausherr and Marc Kaufman for your time & help. I came across following post at iText tech support faq talking about similar topic. https://itextpdf.com/en/resources/faq/technical-support/itext-7/how-decrypt-pdf-document-owner-password
Seems the following pdf file which they have shared is encrypted and does not allow to overwrite the owner password using PDFBox (2.0.15). http://gitlab.itextsupport.com/itext/sandbox/raw/master/resources/pdfs/hello_encrypted2.pdf I'm just wondering how does this works and are there any similar implementation in PDFBox. On Wed, May 22, 2019 at 7:45 AM Marc Kaufman <[email protected]> wrote: > Which is, of course, a violation of the "agreement" between PDF and > Readers (ignored by everyone, it seems, except Adobe). In > Acrobat/Reader, you need to open with the Owner password in order to > change permissions. Opening with the User password should honor > permissions and not allow changing of permissions. > > Marc > > On 5/21/2019 9:42 AM, Tilman Hausherr wrote: > > Am 17.05.2019 um 09:47 schrieb RJC 2009: > >> Here is my test program which is trying to disable the printing > >> option and > >> protect the document with an owner password. > >> > >> However, if I use the resultant PDF and run the program again with a > >> DIFFERENT owner password then it ENABLE the printing option. > >> > >> > >> > >> Basically I need to disable the printing option in PDF with an owner > >> password and the printing option cannot be enabled back without using > >> the > >> original owner password. > > > > > > I should have read the text more carefully (and continue reading after > > "2.0.5"). This is by design. When you open with the user password then > > the file is decrypted and can be manipulated, reencrypted, everything. > > The owner password is just an extra so that a software can decide that > > you're the owner. That is why there are so many tools on the internet > > that allow to change the permissions of PDF files. > > > > Read also this: > > > > https://www.cs.cmu.edu/~dst/Adobe/Gallery/anon21jul01-pdf-encryption.txt > > > > > > Tilman > > > > > > --------------------------------------------------------------------- > > To unsubscribe, e-mail: [email protected] > > For additional commands, e-mail: [email protected] > > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [email protected] > For additional commands, e-mail: [email protected] > >
