Sometimes I think the industry treats humans like they are idiots. In fact the UPnP for example is what "some" people want but why is it turned on by default? WPS is turned on by default and 99% network routers I know have the address range 192.168.1.0/24 by default.
What do I want to say?
Plug your device into anybodies network - if you don't sit at your friends home you should not get an IP like [192.168.1.102]. If you are at your office your admin is a lazy a.. or he/she hates to spend 10 minutes after buying new equipment.
Imagine you've got an IP why not running nmap and search network devices. If you can see your office workstations ip I really would talk to the responsive admin. Now you've got permission to try from home and you know only one tool - the nmap network scanner. Open web browser and go to https://whatismyip.com. Make a nmap scan on the public IP - guess what 30 open ports with port number > 3000. Did admin forget to turn off UPnP on the security cams?
I'm happy that a huge amount of companies do not make these mistakes and this is worst case scenario. But I believe that almost 100% of all companies in the world have anywhere a misconfig anywhere. Searching these lacks of security could be a long story but some are really easy to find and very popular!
Is this hacking?
I would say yes. Finding a vulnerability and using it to break into a system does not base on software vuls. There are much more open gates you can go through which have nothing to do with a software failure. The software could be safe but if admin leaves root/admin as default username/credential the vulnerability is in misconfiguration not in software! Also social engineering is a very popular attack vector. So always think if you know the printer technician personally?