The Register reports
Beating the unique identifiers that printers can add to documents for security purposes is possible: you just need to add extra dots beyond those that security tools already add. The trick is knowing where to add them.
[...] researchers from the Technical University of Dresden [...] Timo Richter, Stephan Escher, Dagmar Schönfeld, and Thorsten Strufe reckon they've cracked the challenge of knowing how to anonymise printed documents, and presented their work to the Association of Computer Machinery's 6th ACM Workshop on Information Hiding and Multimedia Security in Innsbruck, Austria [the week of June 22].
In this paper, the TU Dresden researchers explain that they tested 1,286 documents printed on machines from 18 manufacturers, creating an extraction algorithm to identify well-known dot-patterns--and at the same time, discovering four previously undiscovered patterns coding at 48, 64, 69, and 98 bits.
Identifying new patterns is important, from a privacy point of view, since as the authors points out, an activist in a dictatorship could easily be unmasked by their printer (unless they happen to use a Brother, Samsung, or Tektronix printer, none of which seemed to carry tracking codes, the researchers said).
[...] The group has published [a] toolkit that automates the obfuscation workflow, here.
Previous: "Printer Dot Sanitisation" Software Seeks to Cleanse Yellow-Dot Watermarks
(Score: 4, Interesting) by deimtee on Thursday June 28 2018, @09:13PM (7 children)
If they decode the dot patterns, another interesting project might be to write a program to add user-defined dot codes to Brother, Samsung, or Tektronix printers. Print a different random SN into every document.
If you cough while drinking cheap red wine it really cleans out your sinuses.
(Score: 4, Funny) by DECbot on Thursday June 28 2018, @09:49PM (1 child)
I assume you mean "random" as in "always the username and printer serial number of my smelly, annoying coworker that sits across from me."
cats~$ sudo chown -R us /home/base
(Score: 0) by Anonymous Coward on Sunday July 01 2018, @03:04PM
(Score: 1) by tftp on Friday June 29 2018, @01:34AM (3 children)
(Score: 0) by Anonymous Coward on Friday June 29 2018, @01:45AM (2 children)
I'd prefer HaHa'); DROP TABLE Printers;--
O just Bobby Tables [xkcd.com]
(Score: 2) by maxwell demon on Friday June 29 2018, @07:27AM (1 child)
Since it encodes serial numbers, I suspect the encoding doesn't cover the complete ASCII character set, but only numeric, or at most alphanumeric characters. So, no semicolon or quote for you to add.
The Tao of math: The numbers you can count are not the real numbers.
(Score: 2) by DannyB on Monday July 02 2018, @04:11PM
Does anybody still use ASCII? Try UTF-8!
Characters for line drawing. Playing cards. Musical and mathematical notation. All known human languages. Romulan, Klingon, Vorlon, Minbari, Narn, Cardassian, Centuari, Dwarvish and languages not yet invented. And best of all . . . emojis!
To transfer files: right-click on file, pick Copy. Unplug mouse, plug mouse into other computer. Right-click, paste.
(Score: 0) by Anonymous Coward on Friday June 29 2018, @01:39AM
Just be sure to that the dot pattern matches one of a printer with compatible toner properties to not give away the deception so easily.