Why is this bad? Let's say a hacker knows this, and sets up a network called that, or called "AT&T WiFi" or "Starbucks" or any myriad of commonly-used SSID names. Many devices will connect to it automatically, and voila, he can watch the traffic going across his network, and possibly even hack into that device (computer, phone, etc.).
Are you worried yet? You should be. There are things you can do, however, to help limit the chances of this happening.
- Pay close attention when you are joining a new network. Some devices show a different icon if the network is a normal WiFi router, versus a mobile hotspot (in other words, using someone's cell phone to set up a WiFi hotspot would show as a different icon). If this is the case, and you didn't intend it to be a personal hotspot, then don't join it.
- Verify with the store or hotel you are at, what their WiFi name is. Maybe there are several listed that are spelled similarly.
- Frequently review the list of saved WiFi connections you used in the past, and delete any one you think you will never use again. Below are instructions for how to do this in various devices.
WindowsIn Windows 7, 8, or 10, go to Control Panel, Network and Sharing Center, and click Manage wireless networks (one way to get there is to click on the network icon in the tray, and pick "Network and Sharing Center" from the pop-up menu):
Then, select the network from the list, and pick the Remove button:
AndroidFor Android devices, go to the Settings app, go to WiFi, and simply tap the network in the list, you will have a Forget button to remove it from your list:
Apple Mobile (iOS)For iOS devices, go to Settings, WiFi, and tap the little Info "i" button next to the network name. There will be a "Forget this Network" option
Apple Macintosh (OS X)For a Mac, go to Network Preferences (you can get there easily from the WiFi logo on the system menu). Make sure to unlock the preferences for changes, and then click Advanced:
Finally, don't forget to click Apply to save your changes.
Note that you will have a similar thing for Apple TV, Roku, or any various TV devices, although you may not travel with them, and therefore probably don't join networks. But if you do, think about it.