Comment by twalkz

Comment by twalkz 7 days ago

18 replies

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> My printer does not print tracking dots. Can I hide this fact?

> If there are really no tracking dots, you can either create your own ones (deda_create_dots) or print the calibration page (deda_anonmask_create -w) with another printer and use the mask for your own printer

The thought of being able to “spoof” the tracking dots of another printer has interesting implications for deniability. Though I guess in this case you’d still need access to the original printer to print the anonmask…

decimalenough 7 days ago

Per Wikipedia, the dots' "arrangement encodes the serial number of the device, date and time of the printing", so all you really need to spoof somebody else's printer is the serial number. Which can likely these days even be accessed remotely through printer settings.

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  • CobrastanJorji 7 days ago

    No need to examine the printer. Just find a sheet of paper that printer printed, decode the dots, and then print your super illegal whatever with their printer's dots and a timestamp that makes sense for whatever you're framing them for doing. Nobody's ever gonna believe "the dots were a lie." They sound too much like fingerprints.

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    • dylan604 7 days ago

      Or just go to a big box retailer, grab a couple of serial numbers off of the packaging, and then randomize per page.

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      • thfuran 7 days ago

        Better than nothing, but you probably don't want to produce a document that purports to have been printed by three different printers that were likely only in the same place during a relatively short period surrounding when you went to see them. You'd be better off just making up serial numbers.

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  • timewizard 7 days ago

    It depends on how it gets the serial number. If it reads it from internal memory then spoofing your own serial number on each document print is the obvious workaround.

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tgsovlerkhgsel 7 days ago

Once you are at the level of forensic investigations that go down to the tracking dots, most attempts at spoofing anything will be relatively obvious and provide further evidence that narrows down the list of suspects to those aware of such techniques.

You might fool someone who does such analysis casually but I'd expect an actual experienced investigator to e.g. go "the tracking dots are clearly brand X, but the raster used for greyscale is obviously from Y, soooo"

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  • thinkingemote 7 days ago

    Have these dots been used as evidence in a court?

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    • UncleEntity 7 days ago

      They've been used to figure out who leaked government documents in a few cases IIRC.

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