Blackouts don’t work
It’s been reported that yet again sensitive information has been posted on the web because people don’t understand the difference between what you see and what you get. A pdf document posted by the Civil Aviation Authority contained blacked out sections that were about airport security. However, the sensitive sections could be read quite easily: they just used black on black, or something similar.
Pdf documents contain all the text that was in the document from which they were produced; just because it’s not immediately visible (black on black, or a black block superimposed) it doesn’t mean that it’s disappeared. Just select the text to see it, or if necessary copy and paste into another application, or view the pdf file with a text editor.
November 16th, 2006 at 13:38
“Pdf documents contain all the text that was in the document from which they were produced;” This is misleading. I produce my PDFs using pdflatex from LaTeX files, and I know how to put information in my LaTeX files that will not end up in the PDF! You make this sound like a PDF problem, when in fact it’s more like a WYSIWYG editor problem. The reason I say this is that a semi-rational response to what you wrote would be “oh, we’d better put the .doc files up instead, then, if PDF is so insecure”.
November 28th, 2006 at 22:11
[…] pdf documents contain all the text that was in the document from which they were produced; just because itÂ’s not immediately visible (black on black, or a black block superimposed) it doesnÂ’t mean that itÂ’s disappeared. just select the …Read more: here […]