BLAKE2b produces wrong tag when using `reset()` with a different-length key

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## Summary `hazardous::mac::blake2b::Blake2b::reset()` does not correctly reset the state when a key is supplied that has a different length than the one used upon initialization with `hazardous::mac::blake2b::Blake2b::new()`, because it errorneously uses a cached length. ## Impact Initialization `hazardous::mac::blake2b::Blake2b` with a key of some length `N`, followed by a reset with a key of length `!= N` will produce an incorrect BLAKE2b tag, causing `hazardous::mac::blake2b::Blake2b::verify()` to fail. This means under honest protocol conditions, parties could experience failing tag verifications. ## Resolution Upgrade to `v0.17.16` or `v0.18.1`.

Source published

30 Oct 2026 12:00:00 UTC

Source modified

30 Oct 2026 11:15:02 UTC

Observed here

30 Oct 2026 11:49:33 UTC

Source terms

OSV · upstream source license applies

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