4 lines of code?
Heck I could do 250k worth of damage just by changing a + into a -
Might be extremely dangerous to the operator.. or some other poor guy standing by the machine.. but who cares, I'm 5000 miles away in darkest <insert the name of this week's enemy>
And thats by owning the machine used to store the robot programs......... which is why its wi-fi is turned off..... and a big notice saying "DO NOT CONNECT THISLAPTOP OR THE MACHINES TO THE NETWORK" is over it.
And before the "update update update and you'll be safe" crowd arrive, the machines have notices in the manuals saying "The OS should not be updated and machine manufacturer bears no responsibility if the OS is updated and the machine breaks down/goes mad and kills everyone"
So either security is baked into the controls from the start, or you air gap
Mind you, put the wrong command into the robot's PLC and it goes on a killing spree anyway