“According to Kaspersky Lab data, 7,176 of around 32,000 of public Wi-Fi spots (over 20 percent) in the host cities of the upcoming FIFA World Cup do not use encryption or authentication algorithms,” a report released by the company said, adding that using such networks can lead to leaks of confidential data.

According to the report, all members of the public using unencrypted Wi-Fi connections are leaving themselves open to hackers, who could be lying in wait by these spots.

The three cities with the largest number of unsafe public Wi-Fi spots are St. Petersburg, Kaliningrad and Rostov-on-Don (37, 35 and 32 percent, respectively), while Saransk and Samara are the safest ones (10 and 17 percent of unsafe spots).

Russia will host the 2018 FIFA World Cup from June 14 to July 15, with the games set to be held in Moscow, St. Petersburg, Kaliningrad, Volgograd, Kazan, Nizhny Novgorod, Samara, Saransk, Rostov-on-Don, Yekaterinburg, and Sochi.