The vast majority of us put a ton of exertion into discovering free Wi-Fi, however open Wi-Fi systems have their own particular offer of issues—especially that it’s extremely shaky. Regardless of the possibility that a Wi-Fi arrange has a secret key, other individuals on the system could perceive what you’re doing, or—on the off chance that they were so inclinded—take individual data and passwords. Luckily, there’s a lot you can do to stay safe!
How much harm they can actually do and upto what extent ?
We all use WiFi and it is like treat when ever we get free/public wifi. Bt using a public WiFi is not always safe. It has its own risks. The same features that make free WiFi hotspot desirable for consumers make them desirable for hackers as well,such as- it requires no authentication to establish a network connection. This make very easy for hackers to access the secured devices on the network.
The biggest threat to free WiFi security is the ability for the hacker to position himself between you and the connection point. So instead of talking directly with the hotspot you are sending your information to the Hacker and if this type of thing takes place then hacker has access to every piece of information you are sending out on the Internet. Important emails, credit card information and even important and private information og your business. Once the hacker has that information, he can access your systems and create troubles for you.
Other than all this there are many more risks related to free WiFi. So always try to avoiding using public WiFi.