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Smuggling arbitrary data through an emoji
191–200 of 206 posts
Re: Smuggling arbitrary data through an emoji
#19210 years or so ago I shocked coworkers with using U+202D LEFT-TO-RIGHT OVERRIDE mid in filenames on windows. So funnypicturegnp.exe became funnypictureexe.png Combined with a custom icon for the program that mimics a picture preview it was pretty convincing.
The source code version of that is CVE-2021-42574, and they have a website:
Basically it's possible to hide some code that looks like comments but compiles like code. I seem to recall the CVE status was disputed since many text editors already make these suspicious comments visible.
Re: Smuggling arbitrary data through an emoji
#193I love the idea of using this for LLM output watermarking. It hits the sweet spot - will catch 99% of slop generators with no fuss, since they only copy and paste anyway, almost no impact on other core use cases. I wonder how much you’d embed with each letter or token that’s output - userid, prompt ref, date, token number? I also wonder how this is interpreted in a terminal. Really cool!
Why does anybody think AI watermarking will ever work? Of course it will never work, any watermarking can be instantly & easily stripped... The only real AI protection is to require all human interaction to be signed by a key verified by irl identity and even then that will: A never happen, B be open to abuse by countries with corrupt governments and countries with corrupt governments heavily influenced by private in…
> any watermarking can be instantly & easily stripped...
I think it took a while before printer watermarking (yellow dots) was discovered. It certainly cannot be stripped. It was possibly developed in the mid-80s but not known to the public until mid 2000s.
Re: Smuggling arbitrary data through an emoji
#194Oh this is just the tip of the iceberg when it comes to abusing Unicode! You can use a similar technique to this to overflow the buffer on loads of systems that accept Unicode strings. Normally it just produces an error and/or a crash but sometimes you get lucky and it'll do all sorts of fun things! :) I remember doing penetration testing waaaaaay back in the day (before Python 3 existed) and using mere diacritics to…
Yeah. Zalgo text is a common test for input fields on websites. But it usually doesn't do anything interesting. Maybe an exception trigger on some database length limit. Doesn't typically even kill any processes. The exception is normally just in your thread. You can often trigger it just by disabling JS on even modern forms, but,, at best you're maybe leaking a bit of info if they left debug on and print the stack t…
A few months ago I made a post which I (should've) named "Unicode codepoints that expand or contract when case is changed in UTF-8". A decent parser shouldn't have any issues with things like this, but software that makes bad Unicode assumptions might.
Re: Smuggling arbitrary data through an emoji
#195It's worth noting, just as a curiosity, that screen readers can detect these variation selectors when I navigate by character. For example, if I arrow over the example he provided (I can't paste it here lol), I here: "Smiling face with smiling eyes", "Symbol e zero one five five", "Symbol e zero one five c", "Symbol e zero one five c", "Symbol e zero one five f". This is unfortunately dependent on the speech synthesi…
Ironically enough I have a script that strips all non-ascii characters from my screen reader because I found that _all_ online text was polluted with invisible and annoying to listen to characters.
Mine (NVDA) isn't annoying about non-ASCII symbols, interestingly enough. But for something like this form of Unicode "abuse" (?), if you throw a ton of them into a message or something, they become "lines" I have to arrow past because my screen reader will otherwise remain silent on those lines unless I use say-all (continuous reading for those who don't use screen readers).
Re: Smuggling arbitrary data through an emoji
#196i've found a genuinely useful application of this that isn't just "talk secretively":
I'm part of a community that has a chatroom on both discord and another platform. we have developped a bot that can make the bridge between the two, but it needs to maintain a table in a database of all the bridged messages, so that people use the "reply" feature on either platform, the reply is also performed on the other platform. With this, each platform's bridged message can contain hidden data that points to the other's platform ID, without the need to store it ourselves, and without it being visible to users.
obviously we won't be tearing down the infra already in place anytime soon, so we won't actually be doing that, but that's definitely a useful application for when you don't want to be hosting a database and just wish you could attach additional data to a restrictive format.
Re: Smuggling arbitrary data through an emoji
#197Earlier quoted context omitted.
You can also choose to legally declare that your patents may only be used for defensive purposes. But no one ever does this, because they do not actually intend to use them only for defensive purposes. This is a bogus defense of software patents.
Nope. That’s not how piles of patents are wielded defensively by the big companies. They don’t protect their IP with defensive patents, they defend their company using the threat of using unrelated patents offensively against the attacker.
Yes, I know. That's what this part of my post means:
> may only be used for defensive purposes
It's done with a clause in the public license like "if you sue us, then we revoke this license to you and may in turn sue you." You retain the MAD defensive benefit of the patents, while also not hampering innovation with your patent's existence. If the patents truly exist only for defense, then there is no reason not to do this.
Re: Smuggling arbitrary data through an emoji
#198The title lis little misleading: "Note that the base character does not need to be an emoji – the treatment of variation selectors is the same with regular characters. It’s just more fun with emoji." Using this approach with non-emoji characters makes it more stealth and even more disturbing.
I don't see this as all that disturbing. A detector for it wouldn't be hard to write (variant on something that doesn't actually have variants, flag it!), it seems to me it could be useful for signing things.
Re: Smuggling arbitrary data through an emoji
#199The ability to add watermarks to text is really interesting. Obviously it could be worked around , but could be a good way to subtly watermark e.g. LLM outputs
This is too strippable to be a good watermark, it would only catch the ones who are unaware. The leakers, yes, the cybersecurity people, no.
Rather, I see a use in signing things. Newspapers, politicians etc, generate a unique key and encode it into your article or whatever. Now it's easy for anyone to check if a quote attributed to you actually came from you. Sure, it's not secure but it doesn't need to be because it's simply a stable identifier. Even paywalled sites could display a snippet around the provided quote without being problematic.
Re: Smuggling arbitrary data through an emoji
#200Oh this is just the tip of the iceberg when it comes to abusing Unicode! You can use a similar technique to this to overflow the buffer on loads of systems that accept Unicode strings. Normally it just produces an error and/or a crash but sometimes you get lucky and it'll do all sorts of fun things! :) I remember doing penetration testing waaaaaay back in the day (before Python 3 existed) and using mere diacritics to…
Yeah. Zalgo text is a common test for input fields on websites. But it usually doesn't do anything interesting. Maybe an exception trigger on some database length limit. Doesn't typically even kill any processes. The exception is normally just in your thread. You can often trigger it just by disabling JS on even modern forms, but,, at best you're maybe leaking a bit of info if they left debug on and print the stack t…
Does Zalgo even work on HN? I've never thought of using it to test my systems, thank you. I've got some new testing to do tonight.
Edit: No, Zalgo doesn't work on HN. This comment itself was an experiment to try.