Homomorphic encryption is hyped by computer sciences because it offers great potentials. For example you can perform cloud based calculation while nobody gets to know you data.
I am wondering if there is any homomorphic encryption scheme that is CCA secure. Can't you always just choose a random message, encrypt it and link the ciphertext to the challenge? A decryption oracle will decrypt it without hesitation. As the attacker know one plaintext message, he can easily calculate the second one. By doing so he always wins the CCA experiment.