I have had this before. SSH got corrupted while updating my device to get GCC/make to work. Last time, a couple of years ago, on another WD Live single drive I managed to get hold of an update package that re-installs SSH via the update screen on the WDDRIVE's web page. Very useful indeed.
But I do not know what I did with the file! I have googled around for it, and does not seems to even be mentioned here. But I know it exists and works.
Where can I get it from?
SSH reinstall deb