Hm, why are so many DrayTek routers stuck in a bootloop?

Multiple ISPs reported large numbers of DrayTek gateways repeatedly rebooting and going offline, likely tied to recently disclosed and patched buffer-overflow vulnerabilities in DrayTek firmware; the vendor and ISPs advise firmware upgrades (including TFTP recovery) and disabling remote access/SSL VPN on unpatched devices. Incidents were observed in the UK and reported across Australia and Asia, and the story notes a historical botnet of compromised DrayTek devices, suggesting possible active exploitation of unpatched routers.