using System;

using System.Text;

using System.Security.Cryptography;

using System.IO;

public class Program

{

    public static void Main()

    {

        byte[] cipherText = Convert.FromBase64String("hPAh3+pW5qEEWsjiYM/ZFw==");

        var rawKey = "L4gZCH62iDO8gM5ijyBfCa9ISEBveVIij1Lu0a2IDB4=";

        var rawIV = "OXYRybNW1LBkR56wTxr1kQ==";

        byte[] Key = Convert.FromBase64String(rawKey);

        byte[] IV = Convert.FromBase64String(rawIV);

​

        string plaintext = null;

​

        using (Aes aesAlg = Aes.Create())

        {

            aesAlg.Key = Key;

            aesAlg.IV = IV;

            aesAlg.Mode = CipherMode.CBC;

            aesAlg.BlockSize = 128;

            aesAlg.KeySize = 128;

            aesAlg.Padding = PaddingMode.Zeros;

            using (ICryptoTransform decrypt = aesAlg.CreateDecryptor(aesAlg.Key, aesAlg.IV))

            {

                byte[] decryptedText = decrypt.TransformFinalBlock(cipherText, 0, cipherText.Length);

                plaintext = Encoding.ASCII.GetString(decryptedText);

            }

        }

​

        Console.WriteLine(plaintext);

//      Console.WriteLine(Convert.ToBase64String(plaintext));

    }

}

​

​