Certain worms include a patching step like this when they infect a machine to avoid losing control via re-infection. For a high school science research course

Certain worms include a patching step like this when they infect a machine to avoid losing control via re-infection. For a high school science research course I did an epidemiological modeling study on how "good" reverse-worms might affect the spread of infection, they're a pretty interesting thought experiment. With something involving exponential growth like this, early movers have a significant advantage. As far as I know, there hasn't been a successful reverse-worm that did not accidentally cause worse issues (flooding local networks with a high density set of boxes doing over-zealous scanning, or accidentally destroying boxes due to a slapdash narrowly tested script). Reverse-worms they can either wait around, detecting requests from infected-but-not-patched systems to re-infect and patch them—or just start scanning IP ranges themselves. The former feels somewhat less pernicious. "Try to infect this computer, you will be patched and help patch." But that relies on other worms not patching their zombies.