Decrypting using Azure Key Vault

public SecureString GetSecret()
{
  try
  { 
      // Get the Secret Uri from Key Vault
      string SecretUri = System.Environment.GetEnvironmentVariable("<KeyValutSecretUri>");
      var kvToken = new KeyVaultClient(new KeyVaultClient.AuthenticationCallback(GetToken));
      var kvSecret = kvToken.GetSecretAsync(SecretUri).Result;
      SecureString secpass = new SecureString();
      foreach (char charpass in kvSecret.Value)
      {
          secpass.AppendChar(charpass);
      }
      return secpass;
  }
  catch (Exception ex)
  {
      throw ex;
  }

}

public async Task<string> GetToken(string authority, string resource, string scope)
{
    AuthenticationResult authResult = null;
    try
    {
        string ClientId = System.Environment.GetEnvironmentVariable("ClientId");
        string ClientSecret = System.Environment.GetEnvironmentVariable("ClientSecret");
        var authContext = new AuthenticationContext(authority);
        ClientCredential clientCred = new ClientCredential(ClientId, ClientSecret);
        Task authTask = Task.Run(async () => authResult = await authContext.AcquireTokenAsync(resource, clientCred));
        authTask.Wait();
    }
    catch (Exception ex)
    {
        throw new Exception($"Function Error at Token Retrieval: {ex.Message}");
    }
    if (authResult == null)
        throw new InvalidOperationException("Failed to obtain the JWT token");
    return authResult.AccessToken;
}