{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "cbe640d6cae590b9a7d81ce86fe9a90e83eec1d5"
            },
            {
              "fixed": "b3e647a4aa4d2d054f86a783f5c426035e1dc237"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "7a17308c17880d259105f6e591eb1bc77b9612f0"
            },
            {
              "fixed": "b84eeb7636d6962dd882d5e0b31475e4f404313c"
            },
            {
              "fixed": "01afd198c2c286cd3b81f44d4e33a2e638711550"
            },
            {
              "fixed": "d5541eb148da72d5e0a1bca8ecd171f9fc8b366f"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "6.12.6"
            },
            {
              "fixed": "6.12.96"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.12.96"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.39"
            },
            {
              "fixed": "7.1.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64404.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: ISO: avoid NULL deref of conn in iso_conn_big_sync()\n\niso_conn_big_sync() drops the socket lock to call hci_get_route() and\nthen re-acquires it, but dereferences iso_pi(sk)-\u003econn-\u003ehcon afterwards\nwithout re-checking that conn is still valid.\n\nWhile the lock is dropped, the connection can be torn down under the\nsame socket lock: iso_disconn_cfm() -\u003e iso_conn_del() -\u003e iso_chan_del()\nsets iso_pi(sk)-\u003econn to NULL (and the broadcast teardown path can also\nclear conn-\u003ehcon on its own). When iso_conn_big_sync() re-acquires the\nlock and reads conn-\u003ehcon, conn may be NULL, causing a NULL pointer\ndereference (hcon is the first member of struct iso_conn).\n\nThis path is reached from iso_sock_recvmsg() for a PA-sync broadcast\nsink socket (BT_SK_DEFER_SETUP | BT_SK_PA_SYNC), so the dropped-lock\nwindow can race with connection teardown driven by controller events.\n\nRe-validate iso_pi(sk)-\u003econn and its hcon after re-acquiring the socket\nlock and bail out if the connection went away, as already done in the\nsibling iso_sock_rebind_bc().",
  "id": "CVE-2026-64404",
  "modified": "2026-07-27T03:56:22.169151221Z",
  "published": "2026-07-25T08:50:46.523Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/01afd198c2c286cd3b81f44d4e33a2e638711550"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b3e647a4aa4d2d054f86a783f5c426035e1dc237"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b84eeb7636d6962dd882d5e0b31475e4f404313c"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/d5541eb148da72d5e0a1bca8ecd171f9fc8b366f"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64404.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-64404"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.8.0",
  "summary": "Bluetooth: ISO: avoid NULL deref of conn in iso_conn_big_sync()"
}