PDF File -- Security lock

PDF File -- Security lock

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PDF File -- Security lock timbirr 04-12-2006
Posted by on April 12, 2006, 12:43 pm
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I was looking at a PDF file that was just a companies reproduction of a
product label -- a herbcide, for what its worth.

These labels are mostly long strings of boilerplate language with
safety precautions for use, etc. that can go on for pages upon pages
and are pretty much the same for each herbcide.

There are usually then one or two pages that deal specifically with the
herbicide itself.

So, rather than print off all the pages, I went to copy and paste the
relevant page and found that while I was allowed to print the relevant
document, copy function was disabled.

There was a little gold padlock in the bottom left corner of the
document that so informed me....

It was no big deal and I just typed out what I needed, which took
longer but gave me the same result....and looking back I probably could
have just restricted printing to the page I needed (but didn't think of
that at the time).

Anyway, is this common? Seems like a stupid thing to me -- I mean there
is nothing to stop anyone from "handcopying" as I did, or printing the
doc and then scanning it and then copying it.

Is there a way to defeat?


Posted by Sebastian Gottschalk on April 12, 2006, 12:48 pm
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timbirr@mailcity.com wrote:
> Anyway, is this common? Seems like a stupid thing to me -- I mean
> there is nothing to stop anyone from "handcopying" as I did, or
> printing the doc and then scanning it and then copying it.

It is stupid like any other DRM mechanism.

> Is there a way to defeat?

GhostScript completely ignores this bullshit and Advanced PDF Password
Recovery Pro removes it without reencoding.

Posted by Volker Birk on April 12, 2006, 1:09 pm
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timbirr@mailcity.com wrote:
[PDF clipboard and printing "security"]
> Anyway, is this common? Seems like a stupid thing to me

It is a stupid thing indeed. Next time you could print into a file, for
example as Postscript, and convert this to open PDF again.

Or you could use Free Software like xpdf which ignores this special type
of "security" at all.

Yours,
VB.
--
At first there was the word. And the word was Content-type: text/plain

Posted by Don Kelloway on April 12, 2006, 3:46 pm
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>I was looking at a PDF file that was just a companies reproduction of a
> product label -- a herbcide, for what its worth.
>
> These labels are mostly long strings of boilerplate language with
> safety precautions for use, etc. that can go on for pages upon pages
> and are pretty much the same for each herbcide.
>
> There are usually then one or two pages that deal specifically with the
> herbicide itself.
>
> So, rather than print off all the pages, I went to copy and paste the
> relevant page and found that while I was allowed to print the relevant
> document, copy function was disabled.
>
> There was a little gold padlock in the bottom left corner of the
> document that so informed me....
>
> It was no big deal and I just typed out what I needed, which took
> longer but gave me the same result....and looking back I probably could
> have just restricted printing to the page I needed (but didn't think of
> that at the time).
>
> Anyway, is this common? Seems like a stupid thing to me -- I mean there
> is nothing to stop anyone from "handcopying" as I did, or printing the
> doc and then scanning it and then copying it.
>
> Is there a way to defeat?
>

No. There is no way to prevent someone from handcopying a PDF document
that's been protected, but often the purpose of protecting the document
isn't so much as to prevent copying, but to prevent modification and then
professing it to be something other than what was originally presented.

Whereas the PDF document you refer to contained safety precautions, etc. I
wouldn't be surprised that the intention of the original author was to
prevent modification.

--
Best regards, from Don Kelloway of Commodon Communications
Visit http://www.commodon.com to learn about the "Threats to Your Security
on the Internet".



Posted by Sebastian Gottschalk on April 12, 2006, 3:55 pm
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Don Kelloway wrote:

> No. There is no way to prevent someone from handcopying a PDF document
> that's been protected, but often the purpose of protecting the document
> isn't so much as to prevent copying, but to prevent modification and then
> professing it to be something other than what was originally presented.

Wouldn't a digital signature be sufficient? Anyway, what more could be done?

> Whereas the PDF document you refer to contained safety precautions, etc. I
> wouldn't be surprised that the intention of the original author was to
> prevent modification.

As it can't prevent anything, it's just good for alluring people into
believing and paying this bullshit.

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