QCB is Blindly Unforgeable

ePrint Report: QCB is Blindly Unforgeable

Jannis Leuther, Stefan Lucks

QCB is a proposal for a post-quantum secure, rate-one authenticated encryption with associated data scheme (AEAD) based on classical OCB3 and \(\Theta\)CB, which are vulnerable against a quantum adversary in the Q2 setting. The authors of QCB prove integrity under plus-one unforgeability, whereas the proof of the stronger definition of blind unforgeability has been left as an open problem. After a short overview of QCB and the current state of …

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