Encrypt given data using rc2-40-cbc cipher algo. RC2 with a 40-bit key size in CBC (Cipher Block Chaining) mode, providing encryption by chaining together blocks. Used in environments with key-length restrictions, RC2-40-CBC offered some measure of security, though it was always considered weak. RC2-40-CBC is extremely insecure, vulnerable to modern cryptographic attacks, and should not be used. Our encryption process prepends the IV string used during the encryption process in the encrypted data so that it can be used during decryption.