These vulnerabilities are already patched in the latest beta updates. An update will be released to the public soon.
Until then, use a VPN network.
As you prefer not using VPN:
Some network equipment manufacturers have already pushed updates to fix this. Maybe there’s already a firmware update for your modem/router.
If your iDevices are running iOS 11 and later, the possibility to execute an attack is extremely unlikely, so you should be fine.