{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "e07a06b4eb417f5271d33ce2240e93c62d98b7b4"
            },
            {
              "fixed": "1239ef0fa809b5952fca679db3faa3e1c00e1dac"
            },
            {
              "fixed": "cabd58d9bb66d49d481f762ce986173db397435d"
            },
            {
              "fixed": "93a737e4e042f59673cd580d35214f278d7b757d"
            },
            {
              "fixed": "024e05f73a4c1263d031614bc36700ec135eecb4"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.1.0"
            },
            {
              "fixed": "6.12.113"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.56"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.10"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98736.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: hci_conn: Lock parent access during enhanced SCO setup\n\nBluetooth: hci_conn: Lock parent access during enhanced SCO setup\n\nhci_enhanced_setup_sync() runs on the request workqueue without the\nhci_dev_lock held by its caller when setup was queued. Its CVSD\ncapability check and find_next_esco_param() dereference conn-\u003eparent\nwhile the receive workqueue can unlink and release that parent.\n\nThe following interleaving can cause a use-after-free:\n\n  hci_enhanced_setup_sync()       hci_disconn_complete_evt()\n  load conn-\u003eparent\n                                 hci_dev_lock()\n                                 hci_conn_del(ACL parent)\n                                   unlink SCO child\n                                   drop link's parent reference\n                                   clear child-\u003eparent\n                                   release ACL parent\n                                     bt_link_release()\n                                       kfree(parent)\n                                 hci_dev_unlock()\n  read parent-\u003efeatures[0][3]\n\nThe reference held for the queued SCO child does not keep its ACL parent\nalive after unlinking. Commit 42de40abe25d (\"Bluetooth: hci_conn: fix the\nSCO setup context lifetime\") protects the child stored in the queued\ncontext, but leaves these parent accesses unprotected.\n\nWith a 40 ms diagnostic delay after loading conn-\u003eparent, an instrumented\nkernel based on fd179f8a05be, which already contains 42de40abe25d,\n\n  BUG: KASAN: slab-use-after-free in hci_enhanced_setup_sync+0xda5/0xdf0\n  Read of size 1 at addr ffff888102204047 by task kworker/u17:0/93\n  Call Trace:\n   hci_enhanced_setup_sync+0xda5/0xdf0\n   hci_cmd_sync_work+0x13c/0x290\n   process_one_work+0x6b4/0x10e0\n\n  Allocated by task 92:\n   __hci_conn_add+0x304/0x1df0\n   hci_connect_acl+0x349/0x3e0\n   hci_connect_sco+0x3b/0x9a0\n   sco_sock_connect+0x475/0xca0\n\n  Freed by task 94:\n   kfree+0x121/0x3c0\n   bt_link_release+0x79/0xa0\n   device_release+0xc8/0x240\n   kobject_put+0x14d/0x280\n   hci_conn_del+0x524/0xe30\n   hci_disconn_complete_evt+0x403/0x8c0\n   hci_event_packet+0x71b/0xb20\n   hci_rx_work+0x293/0x730\n\nThe accessed address is 71 bytes into the freed ACL parent, at its\nfeatures[0][3] byte; the queued SCO child is a different object. The\ndiagnostic preserves the loaded parent across the delay, matching the\nunmodified compiled capability check, and does not change the parent\nreferences or teardown path.\n\nHold hci_dev_lock() across the codec switch, including every call to\nfind_next_esco_param(), and release it on all selection errors. Keep\nconfigure_datapath_sync() outside the critical section because it waits\nfor HCI events. Preserve parameter selection and existing return values.",
  "id": "CVE-2026-98736",
  "modified": "2026-10-20T02:30:20.532233317Z",
  "published": "2026-10-18T15:47:14.076Z",
  "references": [
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/024e05f73a4c1263d031614bc36700ec135eecb4"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1239ef0fa809b5952fca679db3faa3e1c00e1dac"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/93a737e4e042f59673cd580d35214f278d7b757d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/cabd58d9bb66d49d481f762ce986173db397435d"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98736.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-98736"
    }
  ],
  "schema_version": "1.9.0",
  "summary": "Bluetooth: hci_conn: Lock parent access during enhanced SCO setup"
}