Is this some James Bond-esque fantasy ?
I thought this was going to be an article about a credible-but-obscure threat. Instead, I get a Rube Goldberg machination that would only work in a Hollywood spy film.
Let's list the setup requirements :
1) a bot-infiltrated network
2) an open scanner next to a window
3) a drone with a laser
4) nobody looking out the window wondering what the heck a drone is doing there while a document is being scanned
5) nobody standing between the scanner and the drone while a document is being scanned
6) the document being scanned is miraculously transparent to laser light while simultaneously being scannable
7) no heavy gust of wind during the entire process
I can accept that, to scan a document, the user leaves the cover open. I have done that very thing every time I had a sheaf of papers to scan. But, if I have a sheaf of papers to scan, I am not moving from in front of the scanner, which would put me squarely in the path of the laser beam. And if I am only scanning one (or two), then I always close the cover.
Plus, on multifunction printers these days, the cover is likely not just a cover, but integrates a paper-feed mechanism that is way too heavy to effectively leave the cover open.
And, if we're talking big multifunction printers, they're in a separate room, likely without windows, or a window high up.
All of that to spend over 3 seconds sending "d x.pdf", which is 7 bytes. God forbid you need to send a dozen ddos orders - you'll be there all day and somebody will end up taking a shotgun to your drone (or, more realistically, calling security).
If this is your solution to sending commands to your virus bot, you're going to die of hunger before next month.