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Be careful what you copy: Invisibly inserting usernames into text

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Re: Be careful what you copy: Invisibly inserting usernames into text

#101

Post by itronitron »

zbobet2012 wrote: post #23
elaus wrote: post #17

Earlier quoted context omitted.

> There are other, far more interesting ways, to watermark text than this that are both harder (to impossible) to detect that produce better results. This sounds interesting, could you elaborate?

The post above mentions some. One good way is synonym replacement. In this method the actual _text_ is altered every time to produce a unique arrangement of synonyms used through out the text. For example I can replace "two" with "2" or "fast" with "quick" to obtain a bit to embed things in. See here for examples: http://failheap-challenge.com/showthread.php?16311-Taking-th... Another is to alter the _frequency_ of c…

interesting, I wonder if that is why there are so many typos and grammatical errors in news articles these days

Re: Be careful what you copy: Invisibly inserting usernames into text

#102

Post by ohitsdom »

zbobet2012 wrote: post #9

I did this (non-publicly) many years ago for my eve online alliance. A substantial problem exists in that forging the identity of _someone else_ is fairly easy in a naive scheme if someone detects these characters. That means you can sow chaos by blaming innocent folks. In practice you'll want to "sign" the inserted data as well. Also because of the overhead here and the fact that you will want the signature to occur…

On forging the identity of someone else, the author did mention it and the workaround is pretty simple (using a secret ID for each user):

> There are some caveats to this method of course. For example, if a user knew of the script they could theoretically insert their own zero-width characters and accuse someone else. A better solution would be to insert a unique user ID that is not publicly available instead of the username.

Re: Be careful what you copy: Invisibly inserting usernames into text

#104

Post by cesarb »

nzpopa wrote: post #57
zbobet2012 wrote: post #9

I did this (non-publicly) many years ago for my eve online alliance. A substantial problem exists in that forging the identity of _someone else_ is fairly easy in a naive scheme if someone detects these characters. That means you can sow chaos by blaming innocent folks. In practice you'll want to "sign" the inserted data as well. Also because of the overhead here and the fact that you will want the signature to occur…

What about fingerprinting a photographed text? I'm thinking that by encoding the hidden message to bits and representing them in spaces around some arbitrary anchor keywords from the original text might work. Extracting the message then requires either OCR, either manual work(counting spaces).

It could also be encoded in the choice of serif or sans-serif for each character: http://elonka.com/friedman/

Re: Be careful what you copy: Invisibly inserting usernames into text

#105

Post by Mashimo »

sshagent wrote: post #71
zbobet2012 wrote: post #9

I did this (non-publicly) many years ago for my eve online alliance. A substantial problem exists in that forging the identity of _someone else_ is fairly easy in a naive scheme if someone detects these characters. That means you can sow chaos by blaming innocent folks. In practice you'll want to "sign" the inserted data as well. Also because of the overhead here and the fact that you will want the signature to occur…

I miss Eve so much, there isn't a mention of Eve on this site that doesn't get me pining for the game again. Sadly everyone i flew with no longer play :/ What the status of the game, last i looked i barely recognised any on the sov/influence map.

Still a lot of people playing it. A bit less subscribers, but not too bad.

In 0.0 it's captials everywhere. People mine in Rorquals, people do PvE in Carriers and Supers. If you tackle a small ships doing PvE it opens a cyno and Captials jump in.

They now have fighters that have good applications against smaller ships. So the good old rock paper scissors for shipssize in eve is not more.

Still a diverse game, from solo to large fleet fights. I have my fun.

Re: Be careful what you copy: Invisibly inserting usernames into text

#106

Post by ksrm »

zbobet2012 wrote: post #9

I did this (non-publicly) many years ago for my eve online alliance. A substantial problem exists in that forging the identity of _someone else_ is fairly easy in a naive scheme if someone detects these characters. That means you can sow chaos by blaming innocent folks. In practice you'll want to "sign" the inserted data as well. Also because of the overhead here and the fact that you will want the signature to occur…

The advantage of putting the (signed) full username in there is that you can demonstrate to a third party (like a court?) who is to blame. Just encoding a number for each user, or giving each user a different number of Es is deniable to a certain extent.

Re: Be careful what you copy: Invisibly inserting usernames into text

#107

Post by colejohnson66 »

megaremote wrote: post #63
skookumchuck wrote: post #53

Earlier quoted context omitted.

> Then how would you indicate that a space or newline is intended? They aren't invisible, you can see the result as spaces and the next line. > how would I indicate that a length of text is to be displayed from right to left when I post Hebrew text to an English-expecting text field? That is also a visible effect.

Nope, not always. Try putting a newline in HTML, it is ignored.

To be fair, that’s because HTML is a descendent of SGML

Re: Be careful what you copy: Invisibly inserting usernames into text

#108

Post by jessriedel »

irrational wrote: post #20

How difficult would it be to write a browser extension to either remove all zero-width characters or somehow make it super obvious that they are being used on the page? I just searched for "zero-width" and "zero width" in Chrome and Firefox's extensions stores, but didn't come up with anything.

Would probably be better to do this at the OS level, no? Just ensure that shift-cmd-V/shift-ctrl-V strips zero-width characters in addition to formatting. I can't think of a situation where I'd want to keep one but not the other, and you could always do that manually if it came up.

Re: Be careful what you copy: Invisibly inserting usernames into text

#109

Post by Rotareti »

JorgeGT wrote: post #64
thedailymail wrote: post #51

In addition to the use of Diff Checker mentioned by the author, spell-checkers will also highlight words that are broken up by zero-width characters.

Sublime Text package "Sublime Gremlins" [1] detected and highlighted the zero-width characters: https://i.imgur.com/LNlcgRK.png --- [1] https://github.com/redoPop/SublimeGremlins

VSCode version: https://github.com/nhoizey/vscode-gremlins

Re: Be careful what you copy: Invisibly inserting usernames into text

#110

Post by sakarisson »

teolandon wrote: post #19

Also be careful of copy-pasting bash commands or install instructions to your terminal, they can contain hidden zero-width malicious commands, as well as a newline at the end to make the command run immediately. Ohmyzsh on my machine detects copy-pasted text and warns you.

Yeah, OhMyZsh also warned me on my Mac. I definitely think it is a must for Unix environments.
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