How to redirect Process' standart input/output (C#, .net 4.5, async code)

StreamPipe.cs

using System;
using System.Diagnostics;
using System.IO;
using System.Threading;
using System.Threading.Tasks;

namespace Test
{
    class Program
    {

        static void Main(string[] args)
        {
            var cmd = new Process
            {
                StartInfo = new ProcessStartInfo("cmd.exe")
                {
                    CreateNoWindow = true,
                    UseShellExecute = false,
                    RedirectStandardInput = true,
                    RedirectStandardOutput = true,
                    RedirectStandardError = true
                }
            };
            cmd.Start();

            StreamPipe pout = new StreamPipe(cmd.StandardOutput.BaseStream, Console.OpenStandardOutput());
            StreamPipe perr = new StreamPipe(cmd.StandardError.BaseStream, Console.OpenStandardError());
            StreamPipe pin = new StreamPipe(Console.OpenStandardInput(), cmd.StandardInput.BaseStream);

            pin.Connect();
            pout.Connect();
            perr.Connect();

            cmd.WaitForExit();
        }
    }

    class StreamPipe
    {
        private const Int32 BufferSize = 4096;

        public Stream Source { get; protected set; }
        public Stream Destination { get; protected set; }

        private CancellationTokenSource _cancellationToken;
        private Task _worker;

        public StreamPipe(Stream source, Stream destination)
        {
            Source = source;
            Destination = destination;
        }

        public StreamPipe Connect()
        {
            _cancellationToken = new CancellationTokenSource();
            _worker = Task.Run(async () =>
            {
                byte[] buffer = new byte[BufferSize];
                while (true)
                {
                    _cancellationToken.Token.ThrowIfCancellationRequested();
                    var count = await Source.ReadAsync(buffer, 0, BufferSize, _cancellationToken.Token);
                    if (count <= 0)
                        break;
                    await Destination.WriteAsync(buffer, 0, count, _cancellationToken.Token);
                    await Destination.FlushAsync(_cancellationToken.Token);
                }
            }, _cancellationToken.Token);
            return this;
        }

        public void Disconnect()
        {
            _cancellationToken.Cancel();
        }
    }
}

Cool!

I'm trying to achieve this on Ubuntu, redirecting streams from and to bash, but
When executing a sudo command, with the password prompt, the password we typed in is partially visible (some characters are shown) and even if we typed in correctly, it will just send to the sudo prompt what is shown.

And any echos on the shell (like our current location) each time command is prompted, is not printed to the console.

Any clue what's going on?