TLDR Tech / Crypto
Poseidon2b is secure!
A researcher has published a point-by-point defense of their Poseidon2b hash function implementation for potential use in Ethereum, asserting it holds against the recently published "Skipping Class" algebraic attack. The paper's exploit targets state widths t=12-24 using a tensor MDS construction. The production instance runs t=4 with a complete external MDS layer, placing it outside the attack's scope. The best published cryptanalysis of the specific parameters (GF(2^128), x^7 S-box, 8 external/58 internal rounds) projects attack work at approximately 2^410, well above the 128-bit security target. The researcher backs the claim with pinned source code and executable audits, inviting targeted cryptanalysis of the exact configuration rather than generalized arguments about Poseidon as a family.
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