Ecrypt data using aes-256-cbc without salt
$ echo 'this is hello world' | openssl aes-256-cbc -a -nosalt -k hello
HEQ/s/mOMof648tJxJvvwtHUTcq2j021RbgvqLA02lY=
-a means encoding the output using base64
-nosalt force openssl do encryption without salt
-k the encryption key