https://devzone.nordicsemi.com/f/nordic-q-a/88055/le-secure-connections-pairing-phase-2Hi,Master: In BT core_v5.0 2.3.5.6.3 Authentication Stage 1 – Passkey Entry, as shown in the figure below Question: Why does the process loop 20 times, verifying one bit each time? Assuming eavesdropping by capturing packets: Loop 20 times Caien-USTelligent Community 13Fri, 20 May 2022 07:02:31 GMThttps://devzone.nordicsemi.com/thread/368718?ContentTypeID=1Fri, 20 May 2022 07:02:31 GMT137ad170-7792-4731-bb38-c0d22fbe4515:c4876e47-75d7-443b-95ee-477188ed52edoutspace<p>Thank you very much for your answer, although I am still a little unclear, but it does not affect my development work, thank you again</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/368629?ContentTypeID=1Thu, 19 May 2022 13:02:08 GMT137ad170-7792-4731-bb38-c0d22fbe4515:93f09932-8918-47cf-a4ec-aaab3604e6e6Kenneth<p>I can find this have also been discussed in this thread:&nbsp;<br /><a href="https://devzone.nordicsemi.com/f/nordic-q-a/82434/nrf52810-passkey-entry/342641#342641">https://devzone.nordicsemi.com/f/nordic-q-a/82434/nrf52810-passkey-entry/342641#342641</a></p> <p>Note that MITM attack breaks legacy pairing with any (even random) passkey from the first attempt. See <a href="https://eprint.iacr.org/2013/309.pdf">eprint.iacr.org/.../309.pdf</a> for the attack details.</p> <p>Best regards,<br />Kenneth</p> <div></div><div style="clear:both;"></div>