Public Wi-Fi is a great place to have your personal information stolen. So many of these places have little if any security on their network and I doubt that the routers are kept up to date. Wi-Fi router updates(Firmware updates) just seem to be an aspect that falls through the cracks. Because of that, these routers can have malicious software installed on them to gather information. If a public network does not have a password on it then look out! Much of your information is transmitted in the clear.
As I’ve said before, I’m not the paranoid type but I DO NOT under any circumstance log into email accounts, financial accounts or any retail accounts using public Wi-Fi. These public Wi-Fi networks are okay for reading the news or general shopping around or getting directions on a map. You really need to be suspicious of the overall security of these networks.
As I said, if a wireless network does not have a password you are transmitting information in the clear. That means that it is not encrypted as it passes over that network. This is what you can potentially have happen because of that. I can sit in a place with public Wi-Fi and use a free piece of software call Wireshark and gather all kinds of login information. If you log into a financial account there is the potential that I can get your login information. The other problem is that when you log into accounts like this they will always ask you to have a one-time code texted or emailed to you in order to verify that it is actually you. This location feature keeps people from logging into your account from any random place. Once you get that text or email to prove that it’s you then you have approved that location for logins into your accounts. Don’t do that!
If you are out somewhere and need to check email or financial information just use your regular cell data. Make sure wi-fi is turned off and that you are using cell data to log in. Public Wi-Fi is great for casual stuff but just be very careful what you use it for.