The guest zone provides internet access for guests without requiring security setups, MAC filtering, or other configurations to occur.
Just call this one the hacker fast lane. A guest zone is usually provided to allow visitors to access the internet through your router. It typically has no access restrictions, requires no special passwords or configuration, and bypasses all security provisions like MAC filtering. This is a free pass for hackers to use your internet services, which is one of the reasons to put security precautions in place to begin with.
It’s kind of like providing a side entrance to your house that doesn’t even have a door on it, never mind locks and cameras - just a sign over it that says “Hackers Welcome.” ANYBODY can connect to a guest zone and use your internet. Depending on your ISP contract, this may cost you in extra bandwidth, or worse.
There are even stories of bad actors using their neighbour’s WiFi for illicit and illegal purposes. They do this because the authorities will trace the illegal activity back to the neighbour’s WiFi router, and blame the neighbour!
Bottom line: Just turn it off!
As a side note: during the experimentation for this article we noticed that some routers said that the guest zone was turned off when it fact it was still on! Double check by trying to search for local WiFi access points with a cellphone or notebook computer. If you see your guest wifi access point still running then you may want to consider getting some assistance to properly turn it off. In our case, it took reflashing the firmware to finally get it to turn off the guest zone on one of the routers.