CVE-2026-43334

HIGH

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

Title source: cna
STIX 2.1

Description

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.

Scores

CVSS v3 8.8
EPSS 0.0025
EPSS Percentile 16.5%
Attack Vector ADJACENT_NETWORK
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Details

Status published
Products (27)
linux/Kernel 3.3.0 - 5.10.253linux
linux/Kernel 5.11.0 - 5.15.203linux
linux/Kernel 5.16.0 - 6.1.168linux
linux/Kernel 6.13.0 - 6.18.22linux
linux/Kernel 6.19.0 - 6.19.12linux
linux/Kernel 6.2.0 - 6.6.134linux
linux/Kernel 6.7.0 - 6.12.81linux
Linux/Linux < 3.3
Linux/Linux 2b64d153a0cc9d2b60e47be013cde8490f16e0a5 - 01bb4045d2306c266178f49ce0c3576d237a3040
Linux/Linux 2b64d153a0cc9d2b60e47be013cde8490f16e0a5 - 425a22c5373d4e1b46492ab869074ebeeade61f3
... and 17 more
Published May 08, 2026
Tracked Since May 08, 2026