aes-256-cbc iv decryption node

function decrypt(text) {
  const [ivStr, encodedStr] = text.split(':')
  const initVector = new Buffer(ivStr, 'base64');
  const decipher = crypto.createDecipheriv(
    'aes-256-cbc', CRYPTO_KEY, initVector
  );
  const encrypted = new Buffer(encodedStr, 'base64');
  let decrypted = Buffer.concat(
    [decipher.update(encrypted), decipher.final()]
  );
  return decrypted.toString();
}