Security Analysis of CPace

In response to standardization requests regarding password-authenticated key exchange (PAKE) protocols, the IRTF working group CFRG has setup a PAKE selection process in 2019, which led of CPace protocol balanced setting, parties share common password. subsequent efforts, further developed, yielding family whose actual security guarantees practical settings are not well understood. this paper, we provide comprehensive analysis universal composability framework. Our is realistic sense that it captures adaptive corruptions and refrains from modeling CPace’s \(\textsf {Map2Pt}\) function maps field elements curve points as an idealized function. order extend our proofs different variants optimized for specific elliptic-curve ecosystems, employ new approach represents assumptions required by proof libraries accessed simulator. By allowing modular replacement used proof, avoids repeated unchanged parts lets us efficiently analyze all variants. As result analysis, investigated enjoy UC security.