Something's thrown DrayTek routers into a bootloop

DrayTek router owners in the UK and beyond had a pretty miserable weekend after some ISPs began to notice a bunch of their customers' gateways going offline. Pretty much overnight on Saturday, a good number of some types of DrayTek routers began rebooting over and over, rendering them inoperable. DrayTek says if that's happening to you, disconnect the router from the internet and try upgrading the firmware. And surely apropos of nothing, don't allow remote administrative access. "The solution is to disconnect the WAN and then try to upgrade to the latest firmware ... Try the [Trivial File Transfer Protocol] TFTP firmware upgrade if the normal upgrade using the web UI does not work," the manufacturer stated Monday. "If remote access is enabled, disable it unless absolutely necessary. Use an access control list (ACL) and enable 2FA if possible. For unpatched routers, disable both remote access (admin) and SSL VPN. Note: ACL doesn’t apply to SSL VPN (Port 443), so temporarily disable SSL VPN until upgraded." The issues, highlighted by ISP Review, showed up on the radar of various telcos. Gamma, which services folks in the UK and Europe, acknowledged that some punters were struggling with their equipment, said the SNAFU wasn't caused by its network, and didn't name DrayTek. Zen, meanwhile, went from fearing a hardware fault within its own network was causing subscribers to drop offline, to confirming it was a problem with DrayTek gear, and shared pretty much the same recovery ins...