Wcf: adding username to message header is safe?

Question

I am connecting to a WCF service in an ASP.NET application. I log in using one username and password and passing the actual whoevever username registered in the ASP.NET web application in the message header, as shown below.

  using (OperationContextScope scope = new OperationContextScope(myService2.InnerChannel))
  {
    Guid myToken = Guid.NewGuid();

    MessageHeader<string> messageHeader = new MessageHeader<string>(HttpContext.Current.User.Identity.Name);
    MessageHeader untyped = messageHeader.GetUntypedHeader("token", "ns");

    OperationContext.Current.OutgoingMessageHeaders.Add(untyped);

    lblResult.Text = myService2.GetData(1231);
  }

I also use the service certificate below

      <serviceCredentials>
        <serviceCertificate findValue="CN=tempCert" />
        <userNameAuthentication userNamePasswordValidationMode="MembershipProvider"
          membershipProviderName="MySqlMembershipProvider" />
      </serviceCredentials>

What bothers me is this protection enough to stop people getting the username stored in the message header?

ASP.NET Configuration

    <system.serviceModel>
    <behaviors>
        <endpointBehaviors>
            <behavior name="NewBehavior">
                <clientCredentials>
                    <serviceCertificate>
                        <authentication revocationMode="NoCheck"/>
                    </serviceCertificate>
                </clientCredentials>
            </behavior>
        </endpointBehaviors>
    </behaviors>
    <bindings>
        <wsHttpBinding>
            <binding name="wsHttpEndpoint" closeTimeout="00:01:00" openTimeout="00:01:00" receiveTimeout="00:10:00" sendTimeout="00:01:00" bypassProxyOnLocal="false" transactionFlow="false" hostNameComparisonMode="StrongWildcard" maxBufferPoolSize="524288" maxReceivedMessageSize="65536" messageEncoding="Text" textEncoding="utf-8" useDefaultWebProxy="true" allowCookies="false">
                <readerQuotas maxDepth="32" maxStringContentLength="8192" maxArrayLength="16384" maxBytesPerRead="4096" maxNameTableCharCount="16384"/>
                <reliableSession ordered="true" inactivityTimeout="00:10:00" enabled="false"/>
                <security mode="Message">
                    <transport clientCredentialType="Windows" proxyCredentialType="None" realm=""/>
                    <message clientCredentialType="UserName" negotiateServiceCredential="true" algorithmSuite="Default" establishSecurityContext="true"/>
                </security>
            </binding>
        </wsHttpBinding>
    </bindings>
    <client>
        <endpoint address="http://localhost/WCFTestService/Service.svc" behaviorConfiguration="NewBehavior" binding="wsHttpBinding" bindingConfiguration="wsHttpEndpoint" contract="WCFTestService.IService" name="wsHttpEndpoint">
            <identity>
                <certificate encodedValue=""/>
            </identity>
        </endpoint>
    </client>
</system.serviceModel>

and on the service side -

  <system.serviceModel>
<bindings>
  <wsHttpBinding>
    <binding name="wsHttpEndpointBinding">
      <security>
        <message clientCredentialType="UserName" />
      </security>
    </binding>
  </wsHttpBinding>
</bindings>
<services>
  <service behaviorConfiguration="ServiceBehavior" name="Service">
    <endpoint address="" binding="wsHttpBinding" bindingConfiguration="wsHttpEndpointBinding"
      name="wsHttpEndpoint" contract="IService">
      <!--<identity>
        <dns value="" />
      </identity>-->
    </endpoint>
    <endpoint address="mex" binding="mexHttpBinding" contract="IMetadataExchange" />
  </service>
</services>
<behaviors>
  <serviceBehaviors>
    <behavior name="ServiceBehavior">
      <serviceMetadata httpGetEnabled="true" />
      <serviceDebug includeExceptionDetailInFaults="false" />
      <serviceCredentials>
        <serviceCertificate findValue="CN=tempCert" />
        <userNameAuthentication userNamePasswordValidationMode="MembershipProvider"
          membershipProviderName="MySqlMembershipProvider" />
      </serviceCredentials>
    </behavior>
  </serviceBehaviors>
</behaviors>

Answer 1

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