Smartphones are going crazy in the Warsaw metro and trains. What’s going on? We know the reason

As has been reported for about a month, Poles have been complaining about numerous cases of strange behavior of smartphones. Devices either prevent normal use or freeze completely. Such cases are said to occur primarily in the Warsaw metro, but not only. Occasionally, similar situations also occur in other public transport vehicles, including trains.

Strange behavior of smartphones in the Warsaw metro

According to the descriptions of people who have encountered the problem, the smartphone suddenly starts displaying a request for pairing from an external Bluetooth device (e.g. headphones). After closing the window, another one, another one, and another one immediately appears. In this way, we can receive dozens of messages about connection attempts within a minute.

Of course, each such window can be closed manually. The problem occurs, however, when the frequency of their pop-ups is so high that it makes it impossible to do anything on the smartphone screen. Moreover, some smartphones (reports indicate mainly iPhones) freeze or turn off in response to such a number of messages.

The only solution seems to be solely a Bluetooth module. However, in many cases it is impossible to touch the appropriate icon in time. Some people also describe that they managed to “save” the hanging phone only after leaving the subway.

We know the reason. Someone has a bad sense of humor

As Niebezpiecznik describes, it is a BLE Spam attack, a classic example of a DoS attack (denial of service – which involves overloading and, as a result, blocking the system or service) using the Bluetooth module. Using an appropriate script, the hacker is able to continuously flood all nearby devices with hundreds of pairing packets. This makes it completely impossible to use most smartphones, and in the case of iPhones (with iOS 17), it often leads to a complete suspension of even a locked phone (and then it is necessary to perform a so-called hard reset).

Of course, it is not clear who carries out such attacks on the subway or other public transport vehicles. Someone probably has a very bad sense of humor and is doing it as a joke. However, the website emphasizes that it does not have to be any outstanding hacker. “Unfortunately, we should expect that there will be more and more situations like the one in the Warsaw metro, because you don’t have to be an outstanding hacker to carry out this attack. All you need is an appropriate application for Flipper Zero or… Android” – write specialists. Danger which shows what people experiencing problems see on their screens.

Experts add that, unfortunately, such attacks are not only not funny, but also – in public places – can be dangerous. It’s not just about the need to “revive” your iPhones (not everyone can do that). Attacks similar to BLE Spam can affect not only smartphones, but also medical implants and even passing cars, blocking their multimedia systems in extreme cases.

How to defend yourself against cyberattacks in the subway?

There is basically only one solution (apart from the possible only telephone). You need to prevent your smartphone from trying to connect to external Bluetooth devices. In the case of iPhones, it is therefore necessary to completely use Bluetooth (which will prevent you from using headphones). Owners of Android smartphones are in a much better situation. In their case, it is enough to uncheck the “Scan for nearby devices” option in the settings. On Windows laptops, only the “Swift Pair” option is available in the Bluetooth settings.