I think chatter is putting it mildly. There's plenty of evidence in this work [1] that is hard to explain. At the very least it's a failed attempt at benchmaxxing the model, but more likely is straight up training on the test set (and the attempt at hiding it failed). Something leaked pretty heavily in their setup.

And there's indications of it happily replying with fake encrypted data in oAI format here [2]. While this is a bit less conclusive than [1], it's still dubious.

[1] - https://r40.org/papers/kimi_k31_benchmark_audit.pdf

[2] - https://x.com/PeterNutter1/status/2118084568419045704

Hypothesis for why K3.1 dropped so much in relative position to other models when AA switched to private evals? Primarily FrontierCode, CritPt V2, and the new private version of AA Omniscience where the model massively underperforms relative to its performance on public benchmarks?