  Non-malleability is an important security property for public-key encryption
(PKE). Its significance is due to the fundamental unachievability of integrity
and authenticity guarantees in this setting, rendering it the strongest
integrity-like property achievable using only PKE, without digital signatures.
In this work, we generalize this notion to the setting of quantum public-key
encryption. Overcoming the notorious "recording barrier" known from
generalizing other integrity-like security notions to quantum encryption, we
generalize one of the equivalent classical definitions, comparison-based
non-malleability, and show how it can be fulfilled. In addition, we explore
one-time non-malleability notions for symmetric-key encryption from the
literature by defining plaintext and ciphertext variants and by characterizing
their relation.

Quantum Physics;Cryptography and Security