A newly identified network access vulnerability has been found in the OS of legacy IoT devices. Which of the following would best mitigate this vulnerability quickly?

Segmentation is the best immediate mitigation. By isolating the vulnerable legacy IoT devices onto a separate network segment, you can restrict their access to critical systems and limit the potential impact of an exploit. This contains the threat while a more permanent solution is developed. Patching is often not an option for legacy IoT devices due to vendor abandonment or hardware limitations. Replacement is a long-term solution, but not a quick mitigation. Insurance is a financial risk transfer mechanism, not a technical control to mitigate the vulnerability itself.