WCF service is configured for client certificate with X509CertificateValidationMode.Custom and a custom X509CertificateValidator.
Binding is WebHttpBinding with WebHttpSecurityMode.Transport and HttpClientCredentialType.Certificate.
This setup enforces the client to provide a certificate attached to the request and its working fine with requests which has the certificate.
Now, I need to process requests which don't have a certificate attached and let them proceed based on some other conditions. but as I've noted it respond 403 before hitting my custom X509CertificateValidator.
How do I hook into WCF requests come without a certificate?