Screenly OSE - hacked

Hey all, I received a message from a client that their screen was replaced by a hacked message with just a twitter link - https://twitter.com/bjh4cker. It was not critical as I just re-setup the card

I believe the issue was when I set this up I had a custom port setup to forward to the internal screenly device, so I believe that is how it was done. Trying to get to the public IP have an authentication popup, failing was an NGINX error.

So, I did remove that port as I can now VPN in and pretty confident that will solve that. But are there any other things known as to why/how this was done (with our without the admin). The OSE doesn’t offer password authentication, but I do see some articles on how to get that.

Thanks.