Ms. Nguyen Thuy - an office worker in District 3, Ho Chi Minh City - said that after connecting to free Wifi at locations around sidewalk cafes or parks, a few days later she often received calls from strange phone numbers advertising services such as tourism, beauty, stock investment...

"To use that free Wifi, Ms. Thuy was required to provide information such as full name, date of birth or age, and some Wifi even required logging into a Facebook account using the link provided by that Wifi. "I wonder if this is the reason why the information was leaked, but I am very concerned whether my information will be taken for fraud or not?" - Ms. Thuy worried.

Meanwhile, Mr. Quoc Tan, an office worker in Ho Chi Minh City, said that when using free Wifi, he felt like someone was eavesdropping and the related website would be displayed a few minutes later.

"For example, if I say I'm going to Phu Quoc, Facebook will show ads for tour packages to go there or Wifi will send a website with similar content and ask users to fill in their name and phone number to continue connecting to Wifi" - Mr. Tan cited.

According to some cybersecurity experts, users can have their data hacked by accessing some fake Wifi access points created by hackers. Then, to use Wifi, users must provide information, which means they have obtained user information.

In addition, with the increasingly strong development of technology, hackers can easily infiltrate public Wifi to scan the devices in use and collect data...

"To avoid being hacked by free Wifi, users need to find out which unit the Wfii network they are about to connect to belongs to. For example, if you are working at ABC unit, ask the manager there first before connecting. Or users can install software such as AVG Antivirus, Kaspersky Mobile Antivirus and Kaspersky Mobile Antivirus to prevent hackers from accessing the device to eavesdrop and steal data" - cyber security experts recommend.

In addition, experts say users should ensure that the website they are accessing uses the HTTPS protocol, with a padlock icon displayed on the browser, which will protect information. In addition, when accessing free Wifi, users should not use accounts related to money such as bank accounts or e-wallets to minimize data leakage.