As has been mentioned, this has been patched already. Run Install Updates now.
After Install Updates, open a terminal:
apt policy wpasupplicant
should return:
Installed: 2.4-0ubuntu6.2
Candidate: 2.4-0ubuntu6.2
If you have 'hostapd' installed too, do:
apt policy hostapd
should return:
Installed: 1:2.4-0ubuntu6.2
Candidate: 1:2.4-0ubuntu6.2
we do not supply hostapd in Linux Lite. You would of had to have installed this yourself at some point.
Now we just have to wait for our:
Mobile phones
Tablets and e-readers that use Wi-Fi
Home and office routers
Home devices like NEST, Amazon Echo and Google Home
Printers, both home and office, that use Wi-Fi
Any other device that uses Wi-Fi
manufacturers to release patches too.
If you are 'super tinfoil' about this, use a 3G/4G connection until your device manufacturer has patched your other device/s and watch your browser address bar, make sure there is https where it should be!