CVE-2026-43334
published 2026-05-08CVE-2026-43334: In the Linux kernel, the following vulnerability has been resolved: Bluetooth: SMP: force responder MITM requirements before building the pairing response…
PriorityP343high8.8CVSS 3.1
AVAACLPRNUINSUCHIHAH
EPSS
0.25%
16.6th percentile
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
18 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| linux | linux | — | — |
| linux | linux | >= 2b64d153a0cc9d2b60e47be013cde8490f16e0a5 < 425a22c5373d4e1b46492ab869074ebeeade61f3 | 425a22c5373d4e1b46492ab869074ebeeade61f3 |
| linux | linux | >= 2b64d153a0cc9d2b60e47be013cde8490f16e0a5 < 7ab69426e7ecbd18a222ee2ec87ca612d30197d7 | 7ab69426e7ecbd18a222ee2ec87ca612d30197d7 |
| linux | linux | >= 2b64d153a0cc9d2b60e47be013cde8490f16e0a5 < 01bb4045d2306c266178f49ce0c3576d237a3040 | 01bb4045d2306c266178f49ce0c3576d237a3040 |
| linux | linux | >= 2b64d153a0cc9d2b60e47be013cde8490f16e0a5 < 91649c02c1baaa18cedf7fb425fa1f0f852c8183 | 91649c02c1baaa18cedf7fb425fa1f0f852c8183 |
| linux | linux | >= 2b64d153a0cc9d2b60e47be013cde8490f16e0a5 < c8ff0ca6508535bccabd81c5c9dcc63de8a3d4fb | c8ff0ca6508535bccabd81c5c9dcc63de8a3d4fb |
| linux | linux | >= 2b64d153a0cc9d2b60e47be013cde8490f16e0a5 < fa14e0e19820b1bbdb42185c9c4efa950bcffef9 | fa14e0e19820b1bbdb42185c9c4efa950bcffef9 |
| linux | linux | >= 2b64d153a0cc9d2b60e47be013cde8490f16e0a5 < ec17efb1ef91506cfd17a77692eaf4bbacb520ea | ec17efb1ef91506cfd17a77692eaf4bbacb520ea |
| linux | linux | >= 2b64d153a0cc9d2b60e47be013cde8490f16e0a5 < d05111bfe37bfd8bd4d2dfe6675d6bdeef43f7c7 | d05111bfe37bfd8bd4d2dfe6675d6bdeef43f7c7 |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | >= 3.3 < 5.10.253 | 5.10.253 |
| linux | linux_kernel | >= 5.11 < 5.15.203 | 5.15.203 |
| linux | linux_kernel | >= 5.16 < 6.1.168 | 6.1.168 |
| linux | linux_kernel | >= 6.13 < 6.18.22 | 6.18.22 |
| linux | linux_kernel | >= 6.19 < 6.19.12 | 6.19.12 |
| linux | linux_kernel | >= 6.2 < 6.6.134 | 6.6.134 |
| linux | linux_kernel | >= 6.7 < 6.12.81 | 6.12.81 |
CVSS provenance
nvdv3.18.8HIGHCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
vendor_redhat8.8HIGH
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VulDB
Linux Kernel up to 6.19.11 Bluetooth smp_cmd_pairing_req channel accessible (WID-SEC-2026-1454)
vuldb·2026-06-18·CVSS 8.8
CVE-2026-43334 [HIGH] Linux Kernel up to 6.19.11 Bluetooth smp_cmd_pairing_req channel accessible (WID-SEC-2026-1454)
A vulnerability classified as critical was found in Linux Kernel up to 6.19.11. The impacted element is the function smp_cmd_pairing_req of the component Bluetooth. Such manipulation leads to channel accessible by non-endpoint.
This vulnerability is listed as CVE-2026-43334. The attack must be carried out from within the local network. There is no available exploit.
Upgrading the affected component is advised.
GHSA
GHSA-3ggx-x2j4-gfqr: In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: SMP: force responder MITM requirements before building the pairing res
ghsa_unreviewed·2026-05-08
CVE-2026-43334 GHSA-3ggx-x2j4-gfqr: In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: SMP: force responder MITM requirements before building the pairing res
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 resp
Red Hat
kernel: Bluetooth: SMP: force responder MITM requirements before building the pairing response
vendor_redhat·2026-05-08·CVSS 8.8
CVE-2026-43334 [HIGH] CWE-322 kernel: Bluetooth: SMP: force responder MITM requirements before building the pairing response
kernel: Bluetooth: SMP: force responder MITM requirements before building the pairing response
A flaw was found in the Linux kernel's Bluetooth Security Manager Protocol (SMP). An attacker could exploit this vulnerability during the Bluetooth pairing process by manipulating authentication requirements. This could lead to the selection of a weaker pairing method than intended, potentially allowing a remote attacker to conduct a Man-in-the-Middle (MITM) attack and intercept or alter communications between paired devices.
Package: kernel (Red Hat Enterprise Linux 10) - Affected
Package: kernel (Red Hat Enterprise Linux 6) - Not affected
Package: kernel (Red Hat Enterprise Linux 7) - Affected
Package: kernel-rt (Red Hat Enterprise Linux 7) - Affected
Package: kernel (Red Hat Enterprise L
No detection rules found.
No public exploits indexed.
https://git.kernel.org/stable/c/01bb4045d2306c266178f49ce0c3576d237a3040https://git.kernel.org/stable/c/425a22c5373d4e1b46492ab869074ebeeade61f3https://git.kernel.org/stable/c/7ab69426e7ecbd18a222ee2ec87ca612d30197d7https://git.kernel.org/stable/c/91649c02c1baaa18cedf7fb425fa1f0f852c8183https://git.kernel.org/stable/c/c8ff0ca6508535bccabd81c5c9dcc63de8a3d4fbhttps://git.kernel.org/stable/c/d05111bfe37bfd8bd4d2dfe6675d6bdeef43f7c7https://git.kernel.org/stable/c/ec17efb1ef91506cfd17a77692eaf4bbacb520eahttps://git.kernel.org/stable/c/fa14e0e19820b1bbdb42185c9c4efa950bcffef9
2026-05-08
Published