HTB:CA2023 Forensics Interstellar Encryption C2 Function

Encryption.cs

private static string Encryption(string key, string un, bool comp = false, byte[] unByte = null)
{
	byte[] array = null;
	if (unByte != null)
	{
		array = unByte;
	}
	else
	{
		array = Encoding.UTF8.GetBytes(un);
	}
	if (comp)
	{
		array = Program.Compress(array);
	}
	string result;
	try
	{
		SymmetricAlgorithm symmetricAlgorithm = Program.CreateCam(key, null, true);
		byte[] second = symmetricAlgorithm.CreateEncryptor().TransformFinalBlock(array, 0, array.Length);
		result = Convert.ToBase64String(Program.Combine(symmetricAlgorithm.IV, second));
	}
	catch
	{
		SymmetricAlgorithm symmetricAlgorithm2 = Program.CreateCam(key, null, false);
		byte[] second2 = symmetricAlgorithm2.CreateEncryptor().TransformFinalBlock(array, 0, array.Length);
		result = Convert.ToBase64String(Program.Combine(symmetricAlgorithm2.IV, second2));
	}
	return result;
}