[pdftex] OT: PDF Security

[Victor Ivrii]

On 5/2/05, Michael Chapman <pdftex at mchapman.com> wrote:
> 
> It's off topic, but seems to be hitting the news this morning (and as
> commented on an other thread the usability of PDFs now and centuries into the
> future does come into play ...)
> 
> "Copy-and-Paste Reveals Classified U.S. Documents
> 
> "In March, U.S. troops in Iraq shot to death Nicola Calipari, the Italian
> intelligence agent that rescued the kidnapped journalist Giuliana Sgrena .
> U.S. commission on the incident produced a report which public version was
> censored for more than one third. Now Italian press is reporting that all
> confidential information in the report is available to the public, just by
> copying "hidden" text from the PDF and pasting it in a word processor."
> 
> The 'before' and 'after' are available at:
> 
> http://www.corriere.it/Media/Documenti/Classified.pdf
> http://www.corriere.it/Media/Documenti/Unclassified.doc
> 
> The 'redacted' version was made with "Acrobat PDFMaker 6.0 for Word"
> with ... yes, you're ahead of me ... with "Security Method: None".
> 
> The producing agency is the same that banned all web (http) connection from
> France Telecom because allegedly/apocryphally they thought their security
> couldn't resist French schoolboys . . .
> 


As usual media is barking on the wrong tree. Document Properties of
the faulty pdf file
show that it was produced by Acrobat PDFMaker 6.0 for MS Word and
authored by richard.thelin. Therefore this dummy painted in MS Word
the words to hide and printed to PDF and the security was violated
with the original MSW document. Definitely in TeX we would not put
\colorbox{black}{foo} around the word foo we want to hide but around
\colorbox{black}{\phantom{foo}}

-- 
========================
Victor Ivrii, Department of Mathematics, University of Toronto