We have recently used a security scanning tool to assess security of an application. It raised a particular configuration as a Medium vulnerability. The claims made in the explanation of the discovered vulnerability don't seem to match with industry standards.

The claim is that "transport mode" security is insecure:

> 
> "Transport mode is the least secure option and should be avoided."
> 
> 
> 

This quote above comes from this article relating to WCF security:  

<https://vulncat.hpefod.com/en/detail?id=desc.semantic.dotnet.wcf_misconfiguration_transport_security_enabled#C%23%2fVB.NET%2fASP.NET>

The claim here made by HP *appears* to be that transport layer security, including SSL and TLS, is *less secure* than message-based security. The article further explicitly states that TLS is *susceptible* to man-in-the-middle (MITM) attack.

Further research into MITM attacks seems to indicate that the **opposite** is true: TLS is the *preferred* way to *prevent* MITM attack. Resources supporting TLS include: 

<https://en.wikipedia.org/wiki/Man-in-the-middle_attack> 

<https://stackoverflow.com/questions/549/the-definitive-guide-to-form-based-website-authentication/477578#477578>

[Do client certificates provide protection against MITM?](https://security.stackexchange.com/questions/26142/do-client-certificates-provide-protection-against-mitm)

So, the question is:  

**Is there any merit in the claim, by the HP article, that transport-mode security is to be avoided, for the reasons cited in that article?**

**UPDATE**: To add some context- the use case in our situation is calling a webservice, not a public site.