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.
Affected products
linux: linux kernel
References8
- git.kernel.org/stable/c/01bb4045d2306c266178f49ce0c3576d237a3040 Patch
- git.kernel.org/stable/c/425a22c5373d4e1b46492ab869074ebeeade61f3 Patch
- git.kernel.org/stable/c/7ab69426e7ecbd18a222ee2ec87ca612d30197d7 Patch
- git.kernel.org/stable/c/91649c02c1baaa18cedf7fb425fa1f0f852c8183 Patch
- git.kernel.org/stable/c/c8ff0ca6508535bccabd81c5c9dcc63de8a3d4fb Patch
- git.kernel.org/stable/c/d05111bfe37bfd8bd4d2dfe6675d6bdeef43f7c7 Patch
- git.kernel.org/stable/c/ec17efb1ef91506cfd17a77692eaf4bbacb520ea Patch
- git.kernel.org/stable/c/fa14e0e19820b1bbdb42185c9c4efa950bcffef9 Patch
Metrics
- CVSS 3.1
-
8.8
HIGH
Score source: CNA
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 20 · as of 13 November 2026
- CWE
- CWE-863
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