Thanks for the update. Unfortunately, most older clients will never see an update. I have noticed that some open-source router firmware have used a workaround to protect older clients. This is from the DD-WRT website and regards adding a setting to “Disable EAPOL Key Retries”:
“An AP-side workaround for key re-installation attacks (KRACK), this option can be used to mitigate KRACK on the station side (router), to help protect client devices that no longer receive updates, or receive updates very slowly. Since many devices out there will not receive an update anytime soon (if at all), it makes sense to include this workaround.”
More information is available here: https://www.dd-wrt.com/wiki/index.php/QCA_wireless_settings#Disable_EAPOL_Key_Retries
Might this be a possibility for Koala?