I just came across this article today explaining the vulnerability CVE-2018-0886 affects all RDP.
https://www.theregister....pport_provider_protocol/ 

I would like to bring this to the RDTab developers' attention.

Thanks for the heads up. Authentication through RD Tabs is facilitated through windows system libraries so the CredSSP patch will also "patch" RD Tabs and no new RD Tabs update will be needed to mitigate this vulnerability. I will probably need to add information to the resulting error message you may receive if the registry settings are deployed as indicated in the link. That won't affect functionality, it would be just to inform users what is happening and that they may need to update their systems.

I just tested on fully patched systems and RD Tabs works fine. Thanks for bring this to my attention, though!