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A case study in PDF forensics: The Epstein PDFs

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Re: A case study in PDF forensics: The Epstein PDFs

#161

Post by vlovich123 »

mikkupikku wrote: post #121
ffsm8 wrote: post #97

Earlier quoted context omitted.

Depending on their technical capability, yes. I mean even in this thread you got what are essentially one-liners to do it. Definitely less hassle then doing it irl

I know I'm not the brightest bulb by any measure, but do some people really take less than at least a few minutes to come up with one-liners for problems as novel as graphical transformations to PDFs? Maybe if the presumed techie hacker / federal worker took it as an amusing challenge I could see this being done, but genuinely out of pure laziness? That's incredible if true.

It’s a mix of “they’ve done it many times before” and these days AI. But remember the “they’ve done it many times before” just means that in a technical and popular forum you’re likely to find the handful of people who have done so regularly enough to remember the one liner. Also this is probably easily searchable as well so even prior to AI not super hard.

Re: A case study in PDF forensics: The Epstein PDFs

#162

Post by foxglacier »

hiccuphippo wrote: post #120
anigbrowl wrote: post #71

I found this part interesting: There are also other documents that appear to simulate a scanned document but completely lack the “real-world noise” expected with physical paper-based workflows. The much crisper images appear almost perfect without random artifacts or background noise, and with the exact same amount of image skew across multiple pages. Thanks to the borders around each page of text, page skew can easi…

I mean, I do that all the time when they ask me to print something, sign it, and then scan it. Sign a blank paper, scan it, paste the original doc on it. Then keep the scan for future docs.

An easier trick I've used is just sign directly on the computer screen over the displayed document with a whiteboard marker and take a photo with my phone.

Re: A case study in PDF forensics: The Epstein PDFs

#163

Post by userbinator »

DavidPeiffer wrote: post #155
culi wrote: post #144

Earlier quoted context omitted.

There was a post on here about a project in stylometry that analyzed HN users comment history. The tool helped find accounts that had an extremely similar writing style to a given account. The site was soon removed due to privacy concerns but many users with multiple account attested to its accuracy https://news.ycombinator.com/item?id=33755016 It turns out stylometry is actually a pretty well-developed field. It mak…

>It makes me wanna write an AI browser assistant that can take my comments and stylize them randomly to make it harder to use these sorts of forensics against me The old trick years ago was to translate from English to different language and back (possibly repeating). I'd be curious how helpful it is against stylometry detection?

The old trick years ago was to translate from English to different language and back (possibly repeating). I'd be curious how helpful it is against stylometry detection?

If you want to be grouped with foreigners who don't know English, it might work well, although word choices may still be distinctive enough to differentiate even when translated.

Re: A case study in PDF forensics: The Epstein PDFs

#164

Post by [deleted] »

mikkupikku wrote: post #89
juujian wrote: post #87

Earlier quoted context omitted.

Not that I can speak from personal experience or anything... But somebody on an email chain may have requested a scanned version of the document to ensure there is no metadata and the employee might have found it easier to just flatten the pdf and apply a graphical filter to make the document appear like a scanned document. There might even be a webtool available somewhere to do so, I wouldn't know...

> the employee might have found it easier to just flatten the pdf and apply a graphical filter to make the document appear like a scanned document Is that remotely plausible? I can't imaging faking a scan being easier than just walking down the hall to the copier room.

[deleted]

Re: A case study in PDF forensics: The Epstein PDFs

#165

Post by wtcactus »

whattheheckheck wrote: post #153
PantaloonFlames wrote: post #136

Earlier quoted context omitted.

And for sure the DOJ knows this, or can know it if they want.

You think the personal lawyers of Donald Trump Pam Bondi and Todd Blanche will follow the money unbiasedly? As well as children's book, The Plot Against the King, author Kash Patel and FBI director? As well as Russian asset herself, Tulsa Gabbard director of National Intelligence want to do anything against their power source?

The democrats had these files and all that information in their power for what? 5 years? And what did they do?

Stop making this a partisan issue. It’s not, and nobody that’s not completely biased beyond any rationality will ever see it as such.

Re: A case study in PDF forensics: The Epstein PDFs

#166

Post by bigyabai »

ttoinou wrote: post #159
whattheheckheck wrote: post #153

Earlier quoted context omitted.

You think the personal lawyers of Donald Trump Pam Bondi and Todd Blanche will follow the money unbiasedly? As well as children's book, The Plot Against the King, author Kash Patel and FBI director? As well as Russian asset herself, Tulsa Gabbard director of National Intelligence want to do anything against their power source?

Yet this was released under their term and not previous presidential terms

> previous presidential terms

Term, not plural. There was one (1) interceding administration following Epstein's death.

Trump promised that the Epstein files would be released if he was reelected, and then withheld files. Congress passed a bill remediating this, hence the newer tranche of files: https://en.wikipedia.org/wiki/Epstein_Files_Transparency_Act

Re: A case study in PDF forensics: The Epstein PDFs

#167

Post by usr1106 »

meinersbur wrote: post #127
mikkupikku wrote: post #89

Earlier quoted context omitted.

> the employee might have found it easier to just flatten the pdf and apply a graphical filter to make the document appear like a scanned document Is that remotely plausible? I can't imaging faking a scan being easier than just walking down the hall to the copier room.

The time advantage of faking a scan becomes better the more pages you have to scan. https://xkcd.com/1205/

Nice. But 5 years seems unrealistic. Who stays on the same job using same processes 5 years these days? Even if the task might remain the same, input formats might change, requiring extra maintenance to the tool. Should recalculate that for 3 years before using it in my automation decisions.

Re: A case study in PDF forensics: The Epstein PDFs

#168

Post by lordgrenville »

tombrossman wrote: post #90
anigbrowl wrote: post #71

I found this part interesting: There are also other documents that appear to simulate a scanned document but completely lack the “real-world noise” expected with physical paper-based workflows. The much crisper images appear almost perfect without random artifacts or background noise, and with the exact same amount of image skew across multiple pages. Thanks to the borders around each page of text, page skew can easi…

GNOME Desktop users can put this in a Bash script in ~/.local/share/nautilus/ for more convincing looking fake PDF scans, accessible from your right-click menu. I do not recall where I copied it from originally to give credit so thanks, random internet person (probably on Stack Exchange). It works perfectly. ROTATION=$(shuf -n 1 -e '-' '')$(shuf -n 1 -e $(seq 0.05 .5)) for pdf in "$@"; do magick -density 150 $pdf \ -…

Nothing about this is specific to GNOME, right? Imagemagick is cross-platform

Re: A case study in PDF forensics: The Epstein PDFs

#169

Post by luplex »

usr1106 wrote: post #167
meinersbur wrote: post #127

Earlier quoted context omitted.

The time advantage of faking a scan becomes better the more pages you have to scan. https://xkcd.com/1205/

Nice. But 5 years seems unrealistic. Who stays on the same job using same processes 5 years these days? Even if the task might remain the same, input formats might change, requiring extra maintenance to the tool. Should recalculate that for 3 years before using it in my automation decisions.

you do not work in the public sector, where processes change rarely, slowly, and partially

Re: A case study in PDF forensics: The Epstein PDFs

#170

Post by nullbio »

anigbrowl wrote: post #71

I found this part interesting: There are also other documents that appear to simulate a scanned document but completely lack the “real-world noise” expected with physical paper-based workflows. The much crisper images appear almost perfect without random artifacts or background noise, and with the exact same amount of image skew across multiple pages. Thanks to the borders around each page of text, page skew can easi…

The real question is: Which of the documents are the ones that are "simulating" scanned documents, and what political narrative do they reinforce?

The only reason I can think of for why someone would want to do this is to pass off fraudulent or AI generated images as real.

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