High 8.8Published May 8, 2026

CVE-2026-43334Bluetooth: SMP: force responder MITM requirements before building the pairing response

Updated under an hour ago (Oct 26, 2026, 5:20 PM ET)

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No exploitation reported and no EPSS estimate yet.

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Exploited in the last 30 days

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.

CVSS: 8.8 HIGH (v3.1, CNA)CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness (CWE): CWE-863
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Linux
NVD analysis: Modified
Record last updated: Oct 19, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Linux Linux linux:linux (from the name)	from 2b64d153a0cc9d2b60e47be013cde8490f16e0a5 before 425a22c5373d4e1b46492ab869074ebeeade61f3; from 2b64d153a0cc9d2b60e47be013cde8490f16e0a5 before 7ab69426e7ecbd18a222ee2ec87ca612d30197d7; 2b64d153a0cc9d2b60e47be013cde8490f16e0a5 builds before 01bb4045d2306c266178f49ce0c3576d237a3040; from 2b64d153a0cc9d2b60e47be013cde8490f16e0a5 before 91649c02c1baaa18cedf7fb425fa1f0f852c8183; from 2b64d153a0cc9d2b60e47be013cde8490f16e0a5 before c8ff0ca6508535bccabd81c5c9dcc63de8a3d4fb; from 2b64d153a0cc9d2b60e47be013cde8490f16e0a5 before fa14e0e19820b1bbdb42185c9c4efa950bcffef9; from 2b64d153a0cc9d2b60e47be013cde8490f16e0a5 before ec17efb1ef91506cfd17a77692eaf4bbacb520ea; from 2b64d153a0cc9d2b60e47be013cde8490f16e0a5 before d05111bfe37bfd8bd4d2dfe6675d6bdeef43f7c7	CNA record
linux linux_kernel linux:linux_kernel	from 3.3 before 5.10.253; from 5.11 before 5.15.203; from 5.16 before 6.1.168; from 6.2 before 6.6.134; from 6.7 before 6.12.81; from 6.13 before 6.18.22; from 6.19 before 6.19.12; 7.0; and 5 more ranges	NVD

References

References

https://git.kernel.org/stable/c/425a22c5373d4e1b46492ab869074ebeeade61f3	patch
https://git.kernel.org/stable/c/7ab69426e7ecbd18a222ee2ec87ca612d30197d7	patch
https://git.kernel.org/stable/c/01bb4045d2306c266178f49ce0c3576d237a3040	patch
https://git.kernel.org/stable/c/91649c02c1baaa18cedf7fb425fa1f0f852c8183	patch
https://git.kernel.org/stable/c/c8ff0ca6508535bccabd81c5c9dcc63de8a3d4fb	patch
https://git.kernel.org/stable/c/fa14e0e19820b1bbdb42185c9c4efa950bcffef9	patch
https://git.kernel.org/stable/c/ec17efb1ef91506cfd17a77692eaf4bbacb520ea	patch
https://git.kernel.org/stable/c/d05111bfe37bfd8bd4d2dfe6675d6bdeef43f7c7	patch

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.