Decrypt given data previously encoded with aes-256-cbc cipher algo. AES with 256-bit key in Cipher Block Chaining (CBC) mode, which introduces an IV to enhance security. One of the most widely used AES modes, employed in SSL/TLS, IPSec, and disk encryption. Secure when used with padding and a random IV, but vulnerable to padding oracle attacks if improperly implemented. Our decryption process assumes the IV string is prepended in the encoded string during the encryption process. You can not decrypt and get the correct results if the IV or passphrase mismatch occurs between encryption and decryption process.