TSA cannot get PDF redaction right.

cryptome.org

31 points·muriithi··9 comments

They should demand that airplanes flying to the US be painted entirely black. That way the terrorists won't be able to see them and blow them up.

http://en.wikipedia.org/wiki/Paint_thinner

Foiled again!

One month ago; http://news.ycombinator.com/item?id=980465

Actually, I think it's just déjà vu plus the TSA never learns: The date on this is December 31!

yeah, it's a different document.

What is the right way to do PDF redaction?

Depends on what you mean by "redaction".

In context, we're talking about removing information from documents, so that partial documents can be released without the removed information being released. The problem is that the PDF format was simply not designed to support that, and the great majority of PDF editing tools (or perhaps all of them??) do not allow for it.

The solution is to create an entirely new PDF, in a way that ensures that the targeted information is not the file. For example, one could take an existing PDF, cover the targeted information with black rectangles, print the resulting document, and then scan the hard copy to create a new PDF.

I suppose one way would be to use an older "portable document" format (aka plain-text) and replace the sensitive text with strings of "x" characters.

They could just create the PDF from the blacked documents in the first place.

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