CVE-2026-43334

In the Linux kernel, the following vulnerability has been resolved:

Bluetooth: SMP: force responder MITM requirements before building the pairing response

smp_cmd_pairing_req() currently builds the pairing response from the

initiator auth_req before enforcing the local BT_SECURITY_HIGH

requirement. If the initiator omits SMP_AUTH_MITM, the response can

also omit it even though the local side still requires MITM.

tk_request() then sees an auth value without SMP_AUTH_MITM and may

select JUST_CFM, making method selection inconsistent with the pairing

policy the responder already enforces.

When the local side requires HIGH security, first verify that MITM can

be achieved from the IO capabilities and then force SMP_AUTH_MITM in the

response in both rsp.auth_req and auth. This keeps the responder auth bits

and later method selection aligned.