CVE-2026-43334

Status: AnalyzedHigh (8.8)—

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

Version: 3.1
Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Base score: 8.8

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.25%
Percentile among all scored CVEs: 15
Score date: 10/5/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

ExploitationT1210 Exploitation of Remote Serviceslateral movement75 %
Primary impactT1556 Modify Authentication Processdefense impairment · persistence · credential access65 %
Secondary impactT1040 Network Sniffingcredential access · discovery60 %

Vulnerabilidad en emparejamiento SMP Bluetooth (red adyacente, AV:A) permite bypass de autenticación MITM; impacto en manipulación de autenticación y posible interceptación de comunicaciones.

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

🛡️ ATT&CK mitigations that cover these techniques

User Account Management Privileged Account Management Network Segmentation Multi-factor Authentication Vulnerability Scanning Threat Intelligence Program

Affected technologies (1)

Linux — Linux Kernel

CWEs

NVD-CWE-noinfo

References

Raw JSON (NVD)

Show

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