Bluetooth: SCO: serialise sco_conn lifetime against sco_recv_scodata()

{
  "id": "15bf42afe2c1ee20c06e4caa38312144bd6b5b181159936cd5421c826125f19e",
  "url": "https://osv.dev/vulnerability/CVE-2026-99011",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Bluetooth: SCO: serialise sco_conn lifetime against sco_recv_scodata()",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: Bluetooth: SCO: serialise sco_conn lifetime against sco_recv_scodata() sco_recv_scodata() upgrades the weak hcon->sco_data back-pointer to a strong reference under hdev->lock: hci_dev_lock(hdev); hcon = hci_conn_hash_lookup_handle(hdev, handle); ... conn = sco_conn_hold_unless_zero(hcon->sco_data); hci_dev_unlock(hdev); but the pointer is cleared from the other side without that lock. When the last sco_conn reference is dropped, sco_conn_free() ran conn->hcon->sco_data = NULL; with no hdev->lock held, so the RX path could read hcon->sco_data and call kref_get_unless_zero() on an sco_conn that was concurrently freed: BUG: KASAN: slab-use-after-free in sco_conn_hold_unless_zero+0xbe/0x160 Write of size 4 by task kworker/u17:0 Workqueue: hci0 hci_rx_work Call Trace: sco_conn_hold_unless_zero+0xbe/0x160 sco_recv_scodata+0x13f/0x490 hci_rx_work+0x3af/0x730 kref_get_unless_zero() only guards against a zero refcount, not against the backing memory already being freed. Give hcon->sco_data an actual reference on the sco_conn it points to, so the object cannot be freed while the pointer is still installed, and only clear and drop it from sco_conn_del(), which runs under hdev->lock (its callers, sco_connect_cfm() and sco_disconn_cfm(), hold it). The reader in sco_recv_scodata() also takes hdev->lock, so the store and the read are now serialised: the RX path either observes NULL or a reference that is guaranteed to stay ",
    "evidence": "osv:CVE-2026-99011",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "6.18.57",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "7.2.11",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-99011",
      "aliases": [
        "CVE-2026-99011"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
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              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
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                {
                  "fixed": "b108ea7ebba147465f4158d8133f0e8f013762ed"
                },
                {
                  "fixed": "8a98d58f6cfe70d51138cd9ce894e72671d95f8a"
                },
                {
                  "fixed": "816fb1590a4c8cf8d05cd076057616be02e276f0"
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          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-99011.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.13.0"
                },
                {
                  "fixed": "6.18.57"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.19.0"
                },
                {
                  "fixed": "7.2.11"
                }
              ]
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          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-99011.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:39.820216594Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/816fb1590a4c8cf8d05cd076057616be02e276f0",
        "https://git.kernel.org/stable/c/8a98d58f6cfe70d51138cd9ce894e72671d95f8a",
        "https://git.kernel.org/stable/c/b108ea7ebba147465f4158d8133f0e8f013762ed",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/99xxx/CVE-2026-99011.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-99011",
        "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/2026/99xxx/CVE-2026-99011.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-99011",
        "evidence": "/id"
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    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 507320,
  "published_at": "2026-10-23T12:20:36.46+00:00"
}