hacking the 777
Indeed it is possible. I wrote a book about just such an event, back before the first a/c was delivered. The book was entitled The Last High Ground, and while the story bears absolutely no resemblance to what we're seeing now (uncommanded throttle-ups and t/r deployments were the plot point), the code inserted into the a/c systems was considered accurate and threatening enough by Boeing for them to ask the publisher to delete it. Which we did.
Robin White