2.11.168 is the latest firmware for My Cloud Mirror gen 1 [1]. 2.30.165 is the latest firmware for My Cloud Mirror gen 2 [2].
Both firmwares were released in Nov 2017, and I suspect the vulnerabilities were fixed at that time as well. At the very least nas_sharing.cgi was removed in both versions. But I haven't had a chance to finish my investigations [3].
From what I can tell the hard-coded backdoor vulnerability was remediated, but I see no indication the unrestricted file upload vulnerability has been remediated in any of the firmwares I tested. But I'm not a security expert. I've reached out to Gulftech and WD for clarification.