I am not a programmer Philip, I just try to figure out what causes a problem and where to fix it. You could change the word update to something else, but anyone looking at the code would do the same in their attack.
This particular security patch is for the Admin Area Only. Hopefully, your Admin area is secure so no one can get into it to begin with. Use common sense and have difficult passwords and change the name of the admin folder. If on Linux type servers, use the .htaccess to ask for a name and password before letting you login to the admin area.