it happens with student machines too
had a similar issue happen in a Tech College (TAFE) here in australia a while back.
One of the classes (not one I taught - this time) was to install a windows server VM and a windows client VM and have the client pickup the dhcp address (and other dhcp settings) from the server.
except (of course) one student reconfigured their VM network and went into 'bridged' mode.
of course, after a while - after the class was finished and the students had left - the local IT support guy comes in not happy about a rogue dhcp server from "that room". of course, we couldn't log on as the student, and many had just locked the machine and left their session (and VMs) running.
so, mad panic "what do we do???"
I just started walking around, press and hold the power button until each machine had shut down - "there, fixed". and then suggested the teacher have a good hard talk with the class about rogue dhcp servers. did anyone lose work? maybe. don't care. needs must.