변조불가능성 like Man-in-the-middle
A scheme is malleable if it is possible to modify a ciphertext and thereby cause a predictable change to the plaintext. So, Malleability can be dangerous.
Provable security is not sufficient to imply non-malleability. (One-time Pad is trivially malleable). Secrecy and integrity are orthogonal concerns.
Confidentiality (Provable security) + Origin Authentication = Non Malleability
How to fix
- CRC 완전히 달성은 못함