Fooling around with encrypted reasoning blobs

(blog.cryptographyengineering.com)

48 points | by supermatou 3 days ago

5 comments

  • Groxx 1 hour ago
    One possible use for the "replay across accounts": if you can get a reasoning block that jailbreaks the model, you could share that block without sharing how you did it, and others can immediately take advantage of it too.
  • glitchc 1 hour ago
    Very interesting. The state management is the really insightful find here.

    I always wondered how these large AI companies managed access for millions of simultaneous users without having to allocate a dedicated LLM instance for each user. Pushing the complete state down to the user after every call makes perfect sense. The LLM itself stays memoryless and ready to respond to an arbitrary prompt. Very nice.

    • geocar 1 hour ago
      N.B. This is exactly how seaside, vba, and even arc[1] do server-side state generally: by encrypting the blob-representing-state and sending to the client to be sent back on future requests (where it will be decrypted and rehydrated).

      It's an old trick that everyone designing protocols should know, since there are lots of applications beyond AI companies.

      [1]: As in, pg's lisp: https://arclanguage.github.io/ref/srv.html#:~:text=The%20pre...

  • Reubend 2 hours ago
    Super cool side channel attack. I tend to agree that it's pretty impractical, but it's such a fun discovery!
  • Retr0id 3 hours ago
    Very cool idea to use thinking duration (either in tokens or in wall time) as a side-channel!
  • haeseong 56 minutes ago
    [dead]