So if I opt out, there won't be a hotspot broadcasting from my hub, but I will be able to have my private WiFi from hub?
What you are seeing on the hub manager, are devices that are connecting to BT Wifi. If you look carefully, you will see that the IP adresses allocated to them begin with a 10.xx.xx.xx.
This is a separate IP subnet to the 192.168.1.xx that is allocated to your home network.
As its been said, if you are not happy, then opt out, but you will lose access to other hotspots when you are away from home.
The other option would be to use a third party router, as they do not transmit BT Wifi etc, and you can still stay opted in and use other hotspots.
I have no idea what you are talking about when you say you "listened for any new shares which I created randomly to check it and they were there"
I suspect that whatever you are doing or seeing has nothing to do with being connected to BTWifi because as has been stated, BTWifi is totally separate from the home network of the BT Homehub that is transmitting it.
The only possible explanation, and I don't know if it is possible, if you can access somebody else phone's shared folder while on BTWifi it is because the the person who's shared folder you can access are using the BTWifi and have not set their phone's shared folders to turn off while on a public network.
This is not the fault with BTWifi it is the fault of the phone users not having a clue about personal security while using public networks.
Nobody will be able to access your private Home network while using BTWifi.
Ok, since there's a lot of misunderstanding, let me show you what I experienced. My network:
1st example: On Main PC, I created some shares. Random folder with a single photo. I could access it through Laptop, 2nd laptop and Random phone by simply using "net share" command in cmd on windows. So, basically, everyone who was connected to BT WiFi could find it.
2nd example: From Main PC and Laptop with shares, I could access shares from 2nd laptop which was connected to BT WiFi. Shares supposed to be able to be accessed only by LAN.
3rd example: I just checked if I can access a USB connected straight to HUB. I could, from private WiFi, BT WiFi and Cable connected PC...
I already disabled all WiFi and waiting for delivery of off brand router, but still. Don't share anything private with your network if you use BT Hub...
@LordWazon Just in case three people telling you the networks are completely separate and there is no security risk, here is a fourth.
Do you seriously think a company such as BT would operate a system that allowed anybody to connect to private networks?
What I really find amazing is that you are the only one out of over a million BT customers that has found this serious security flaw!!
If you dont want to opt out of the Openzone but dont want it to function on your system, you could just get a different non BT VDSL modem/router.
lots to choose, I use a Draytek Vigor 130 as the modem into a Netgear R7800.
Not only does it not have an Openzone/Fon wifi transmission, its not commandable by BT/Openreach so it doesnt shutdown and restart like mine and many other users suffered for awhile after a firmware update a few years ago.
That said, you cant hack into your home network from connecting to it.