10 - BruCON 0x0B - Defeating Bluetooth Low Energy 5 PRNG for fun and jamming - Damien Cauquil

Опубликовано: 05 Апрель 2025
на канале: BruCON Security Conference

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Bluetooth Low energy version 5 has been published in late 2016, but we still have
no sniffer supporting this specific version (and not that much compatible devices
as well). The problem is this new version introduces a new channel hopping algorithm
that renders previous sniffing tools useless as devices can no longer be attacked
and connections analyzed. This new algorithm is based on a brand new pseudo-random
number generator (PRNG) to provide better collision avoidance while kicking out
all of our good old sniffing tools.

Unless some random hacker manages to break this not-that-strong PRNG and upgrades
his BLE sniffing tool to support this algorithm ;). In this talk, we will explain
why this PRNG is vulnerable and how it can be easily defeated to sniff and jam
communications between two BLE 5 devices. A new version of BtleJack will be
released during this talk, providing an efficient way to sniff BLE 5 connections
to our fellow IoT hacker family.