Argon2id password derivation
Password key derivation moved from PBKDF2 to Argon2id to increase the cost of offline guessing against stored verifier material.
Mohith / 3 min readWhat changed
Client password derivation moved to Argon2id before commitment or proof material is generated. The change raises offline guessing cost if password-derived verifier material is exposed.
Derivation remains on the client side of the password boundary. The engine receives the derived commitment or proof inputs required by the protocol, not the plaintext password.
Boundary
Argon2id does not make weak passwords safe and does not remove breach response. A leaked password-derived commitment can still be tested offline.
Parameters must remain compatible between client generation and verifier expectations. Changes require versioned migration and test vectors rather than an uncoordinated server-only adjustment.