Abstract：The definition and related conclusions of chosen ciphertext security IND-CCA (INDistinguishability against adaptive-Chosen Ciphertext Attack) of hybrid encryption of symmetric and asymmetric encryption are discussed. Having studied two kinds of hybrid encryptions of different use and their security definitions, it is found that there is a difference in the oracles. Then the definition of IND-CCA is unified as security for the adversaries can only access the whole decryption oracle of hybrid schemes, which makes the unification of security conclusions of hybrid schemes possible, and supplies the ground for proper use of hybrid schemes. A hybrid scheme called REACT+ has been proposed with its security proof.
2005, Vol. 27 
