.esp files and script blocking

Peter Bonivart peter at UCGBOOK.COM
Fri Aug 6 22:41:17 IST 2004

Dan Farmer wrote:
> I think a better question is why is an eps file (encapsulated
> postscript) considered a script - I'd propose that it might be
> misclassified. Yes, the word script is in the name, but postscript is a
> programming language for describing a printed page, which can be
> rendered to either a postscript printer, or a screen if you have
> ghostscript or another software postscript renderer installed - in my
> eyes its file type should be classified as an image like gif, jpg, or
> pdf (which grew from postscript).

You answered that one yourself, it is a script.

> Maybe I'm forgetting something important about postscript, but I don't
> think I've ever heard of a postscript virus, trojan, exploit, etc. How
> could this possibly be considered dangerous content when compared to
> real scripting languages like shell, perl, javascript, applescript etc.

MS uses the unix file command which in turn uses the magic file to
determine the type of file. It identifies files with no regard to
whether they are dangerous or not. The classification has nothing to do
with MS at all, it's just a way of unix knowing file content without
using file suffixes like lesser OS:es. Maybe you could look at "man
magic" to find out how to make a unique signature for postscript files.

I don't see any reason to block scripts as file types though.

/Peter Bonivart

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