How to check if PDF was modified

pdf trace
stan picture stan · Nov 2, 2009 · Viewed 82.6k times · Source

I have a PDF generated by 3rd party system. Using PDF editor or els software I have modified it.
Is it possible to detect if PDF file was modified, without original file?

I will add some more details.

There is no encryption and no signature features.

Document is created by IT system. User receives document and modifies it.

Is it possible to track that change somehow?

I thought that all these applications leaves some data in PDF header or somewhere encoded inside file and it is possible to check it. However properties showed by windows explorer shows nothing... so I was interested if there is something smarter than viewing properties/header in explorer.

Answer

Bartek picture Bartek · Nov 2, 2009

You could always check the md5sum of the pdf file. I'm not sure what environment you are using but that should help get you started.

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