Please try to add winpty
before oppenssl:
winpty openssl ...
or you can run a new bash wrapped by winpty:
winpty bash
In the windows console, there is some problem with terminal input/output so winpty can help if some software requires unix
terminal behavior.
winpty
helped me to run openssl in this environment:
git version 2.7.3.windows.1
OpenSSL 1.0.2g 1 Mar 2016