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CVE-2026-43334

Full vulnerability record from the local CVENow database.

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.

Severity
HIGH
CVSS score
8.8 (v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-05-08 14:16:43.130000
Last modified
2026-10-19 20:18:14.203000
View original CVE JSON 
{
  "id": "CVE-2026-43334",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-05-08T14:16:43.130",
  "lastModified": "2026-10-19T20:18:14.203",
  "vulnStatus": "Modified",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: SMP: force responder MITM requirements before building the pairing response\n\nsmp_cmd_pairing_req() currently builds the pairing response from the\ninitiator auth_req before enforcing the local BT_SECURITY_HIGH\nrequirement. If the initiator omits SMP_AUTH_MITM, the response can\nalso omit it even though the local side still requires MITM.\n\ntk_request() then sees an auth value without SMP_AUTH_MITM and may\nselect JUST_CFM, making method selection inconsistent with the pairing\npolicy the responder already enforces.\n\nWhen the local side requires HIGH security, first verify that MITM can\nbe achieved from the IO capabilities and then force SMP_AUTH_MITM in the\nresponse in both rsp.auth_req and auth. This keeps the responder auth bits\nand later method selection aligned."
    }
  ],
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          "baseScore": 8.8,
          "baseSeverity": "HIGH",
          "attackVector": "ADJACENT_NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
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