Decrypt given data previously encoded with rc2-cfb cipher algo. RC2 in CFB (Cipher Feedback) mode, turning the block cipher into a stream cipher with feedback. CFB mode was used with RC2 to provide better encryption for data streams, though it still had vulnerabilities. RC2-CFB suffers from the inherent weaknesses of the RC2 algorithm and should not be used for secure communications. 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.