Recently there was an exploit discovered in the RDP protocol implementation of Microsoft. Because RubyRDP uses this for connecting to servers it is important to know this. In a new update with version 3.8.0.0 an option is implemented to help you with this bug as it is still not and will likely not be patched by Microsoft. The full article can be found under here by Check Point however the recommendation is that until a patch is available that you turn off clipboard redirection.
In previous versions of my client it was turned on by default and not available to be changed however from 3.8.0.0 and moving forward you are able to turn it off if you wish. Please understand that the application that I write is just a simple wrapper around Microsoft’s RDP implementation. If you would like the exploit to be patched redirect (no pun intented) your attention to them.
My advise is please update to 3.8.0.0 and disable Clipboard Redirection in the options menu.
https://research.checkpoint.com/reverse-rdp-attack-code-execution-on-rdp-clients/