usb: typec: ucsi: validate connector number in ucsi_notify_common()

{
  "id": "51c407b328d2c46de3fa4e25f0b29ee37903553222207ce8a0fdfe2a5fc47f61",
  "url": "https://osv.dev/vulnerability/CVE-2026-31729",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "usb: typec: ucsi: validate connector number in ucsi_notify_common()",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: usb: typec: ucsi: validate connector number in ucsi_notify_common() The connector number extracted from CCI via UCSI_CCI_CONNECTOR() is a 7-bit field (0-127) that is used to index into the connector array in ucsi_connector_change(). However, the array is only allocated for the number of connectors reported by the device (typically 2-4 entries). A malicious or malfunctioning device could report an out-of-range connector number in the CCI, causing an out-of-bounds array access in ucsi_connector_change(). Add a bounds check in ucsi_notify_common(), the central point where CCI is parsed after arriving from hardware, so that bogus connector numbers are rejected before they propagate further.",
    "evidence": "osv:CVE-2026-31729",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "6.12.81",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.18.22",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.19.12",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2026-31729",
      "aliases": [
        "CVE-2026-31729"
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "bdc62f2bae8fb0e8e99574de5232f0a3c54a27df"
                },
                {
                  "fixed": "f6dcbf2b024d55549959402f1db6c614e51d52cb"
                },
                {
                  "fixed": "f4e608fe12b7ac6a4a57176ab0296bb5a110a078"
                },
                {
                  "fixed": "98429e9ec89a5e3a204112dfaa2dbe6ca28493a0"
                },
                {
                  "fixed": "d2d8c17ac01a1b1f638ea5d340a884ccc5015186"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-31729.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.5.0"
                },
                {
                  "fixed": "6.12.81"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.13.0"
                },
                {
                  "fixed": "6.18.22"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.19.0"
                },
                {
                  "fixed": "6.19.12"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-31729.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:31.081073660Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/98429e9ec89a5e3a204112dfaa2dbe6ca28493a0",
        "https://git.kernel.org/stable/c/d2d8c17ac01a1b1f638ea5d340a884ccc5015186",
        "https://git.kernel.org/stable/c/f4e608fe12b7ac6a4a57176ab0296bb5a110a078",
        "https://git.kernel.org/stable/c/f6dcbf2b024d55549959402f1db6c614e51d52cb",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31729.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-31729",
        "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
      ],
      "provider_metadata": {
        "cna_assigner": "Linux",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31729.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-31729",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 497893,
  "published_at": "2026-05-01T14:14:28.868+00:00"
}