WD claims to have fixed security issues with this new firmware release but when I check the version numbers for several important components, they are the same as in the previous firmware version. Of course it is possible, that WD backported the security patches to their packages but this seems just too weird to me.
They claim to fix a vulnerability related to remote access.
Nothing more specific in the release notes.
That may mean they only modified the REST API, which you wouldn’t be able to see by checking library version numbers…
you will get the problem to ethernet speed (just reach 100 mb instead of 1 gigabit)