Dear white hat attackers,
recently we observed a number of Redis instances that were targeted by a simple attack,
consisting in setting a password using the
CONFIG SET requirepass <password> command
to instances which are left open on the internet.
This is, in my opinion, a good idea, since those Redis instances are going to be cracked anyway. I believe you are doing this in order to make Redis users aware they forgot to setup firewalling rules in order to make their instances not reachable from the outside.