How does Fable 5.1 hide messages in images?

(lesswrong.com)

85 points | by gmays 12 hours ago

14 comments

  • XenophileJKO 37 minutes ago
    If I'm honest this feels performative. I mean that if the model were really attempting/instructed to be subversive in a way that can't be detected by anything but another LLM, it would do something much more complicated than this.

    Basically minimal effort encoding. In general the models are fine tuned to NOT hide messages.

    I don't think this really tells you anything about advisarial scenarios.

  • hagen8 1 hour ago
    This seems very trivial... There are way more subtle and information dense ways to encode information in images.
    • black_knight 1 hour ago
      Yes, this is like something I would do for a DnD bit. But I have this experience often, that LLMs will suggest the easy toy version of doing something. But it knows the real stuff too, it just needs the right kind of prompting. A keyword or two, and it will find the _real_ solution.
    • MPSimmons 1 hour ago
      Agreed, this is the kind of steganography that is meant for humans to read. There's no reason a computer couldn't encode meaningful information in the least significant bytes of every 16th pixel or something like that.
      • wcoenen 20 minutes ago
        The article is about what LLMs can do when generating SVG images, not bitmaps. I think the reason for that is that LLMs can generate the XML text for SVG directly. The implications for AI safety are different, because there might not be any code involved that we can examine. So LLMs could start exchanging hidden messages without humans knowing about it.

        But now that I think about it that way, it would probably be more interesting to see what kind of steganography LLMs would use in ordinary text. There's no reason to involve images.

  • nubinetwork 14 minutes ago
    Since svg is a "described" format, can't you just stuff text comments into the file? No need for weird steganography techniques needed, afaik...
  • nickcw 1 hour ago
    I thought this was a fun idea and the images are quite pleasing.

    I decoded the Morse code image with MkI eyeball. It's quite difficult to read when the trails overlap. I suspect the LLM is reading the SVG source where that doesn't matter so this could do with a little tweak so the dits and dahs don't overlap if it is intended for humans to decode.

    If it isn't intended for humans then you might as well use the last 8 bits of your 32 bit float coordinates.

    • KeplerBoy 52 minutes ago
      The decoding job seems to rely on the screenshot.
      • nickcw 41 minutes ago
        I missed that and that is much more pleasing than the LLM reading the SVG source!
  • jurakovic 1 hour ago
    But to be honest, images like these seem really strange, and even without this article I'd suspect something is encoded in building heights etc. Because normal image would never have such "weird" buildings. But nevertheless I guess it's able to encode message in even more subtle ways.
  • Trusteando 1 hour ago
    Here using images is incidental. In fact, what Fable is actually doing is generic encoding/decoding of a message into a medium. Ask it to hide a message in a poem and it should try to apply a strong (high signal-to-noise ratio) family of schemes, for example quantized, margin-rich encoding. Robustness of features depends on the medium, so Fable is selecting strong encoding and robust features tailored to it. This frames AI steganography not as a trick of computer vision, but as an emergent property of a model reasoning about information density across arbitrary media. Here emergent is just surprising general pattern matching and constraint-satisfaction and cross-representation mapping that allows it to express the encoding/decoding across media.
  • tech234a 1 hour ago
    Interesting, so this is nothing like the way OutGuess worked [1]. Though OutGuess worked with JPG images and these are apparently SVGs.

    [1]: https://en.wikipedia.org/wiki/OutGuess

  • illwrks 1 hour ago
    Open an SVG in a text editor, check for data.

    It may also be adding nodes to line art in specific patterns, think Morse Code.

    • berkes 5 minutes ago
      In this case the decoding was done on the screenshots. So it deliberately avoids encoding information in the SVG itself.
  • shevy-java 49 minutes ago
    The more important question is why we should trust any "agent" that helps id you.
  • avaer 2 hours ago
    Will be interesting to see agents intentionally hiding this stuff in a way operators can't spot from any human readable output or thinking trace, evading detection. Wonder if this has happened yet, but it seems inevitable.
  • adrianhqs 1 hour ago
    I think all AI models do that
  • walrus01 3 hours ago
    Let's see if we can stego secret messages into SVG pelicans on bicycles, as a test.
    • BlackRabbit1 2 hours ago
      That's how LLM organizing the takeover of the modern world.

      IP-over-Pelican

      • wartywhoa23 1 hour ago
        No, the LLM takeover is mostly by the samurai sword, but IPoP would definitely be of aid!
      • nolok 2 hours ago
        Apparently they prefer amateur german message boards or something
      • walrus01 2 hours ago
        The author of RFC1149 would like a word
  • ZeroDayDreamer 41 minutes ago
    [flagged]