{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2024-56591",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2024-12-27T14:03:06.003Z",
        "datePublished": "2024-12-27T14:50:58.674Z",
        "dateUpdated": "2026-08-05T11:45:13.959Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-08-05T11:45:13.959Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: hci_conn: Use disable_delayed_work_sync\n\nThis makes use of disable_delayed_work_sync instead\ncancel_delayed_work_sync as it not only cancel the ongoing work but also\ndisables new submit which is disarable since the object holding the work\nis about to be freed."
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "version": "3.1",
                        "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
                        "baseScore": 8.8,
                        "baseSeverity": "HIGH"
                    },
                    "scenarios": [
                        {
                            "lang": "en",
                            "value": "AV:A - The vulnerable teardown path lives in the Bluetooth HCI connection layer and is driven by connection setup/disconnect events from a peer device, so the attacker must be within Bluetooth radio range of the target. Per kernel scoring convention Bluetooth reachability is Adjacent.\nAC:L - Although this is a race, the attacker controls both sides of it — repeatedly initiating and abruptly dropping L2CAP/LE connections drives `hci_conn_del()` on the HCI event path while concurrent channel teardown calls `hci_conn_drop()` and re-arms `disc_work`. The attempt can be retried indefinitely with no condition outside the attacker's influence.\nPR:N - No privileges on the target are required: L2CAP/LE connection establishment and teardown occur before pairing or authentication, and no capability check exists anywhere on the path from packet/event handling to `hci_conn_del()`.\nUI:N - The entire sequence is driven by attacker-initiated link establishment and disconnection handled automatically by the kernel's HCI event processing. No action by a local user or victim is needed.\nS:U - The use-after-free corrupts kernel heap memory within the same kernel security authority, with no crossing of a VM, IOMMU, or sandbox boundary.\nC:H - The re-armed delayed work leaves an armed timer and workqueue linkage inside a freed `hci_conn` slab object, and `hci_conn_timeout()`/`hci_conn_idle()` subsequently read attacker-groomed reallocated memory. This use-after-free gives an arbitrary kernel read primitive and can leak arbitrary kernel memory.\nI:H - `queue_delayed_work()`/`cancel_delayed_work()` write into the freed object, and the pending timer's `->function` and the work's `->func` are later dereferenced out of it, so heap spraying yields a controlled write and an indirect call — sufficient for control-flow hijack and kernel privilege escalation.\nA:H - Even unexploited, the use-after-free dereferences freed slab memory from timer softirq and workqueue context, producing KASAN splats, oopses, or a kernel panic, which syzbot reproduced reliably."
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "net/bluetooth/hci_conn.c"
                    ],
                    "versions": [
                        {
                            "version": "19c40e3bcaf2d969f5d4ee85bbe1330b54d36d9c",
                            "lessThan": "c55a4c5a04bae40dcdc1e1c19d8eb79a06fb3397",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "19c40e3bcaf2d969f5d4ee85bbe1330b54d36d9c",
                            "lessThan": "2b0f2fc9ed62e73c95df1fa8ed2ba3dac54699df",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "net/bluetooth/hci_conn.c"
                    ],
                    "versions": [
                        {
                            "version": "3.3",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "3.3",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.5",
                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.13",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }
            ],
            "cpeApplicability": [
                {
                    "nodes": [
                        {
                            "operator": "OR",
                            "negate": false,
                            "cpeMatch": [
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "3.3",
                                    "versionEndExcluding": "6.12.5"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "3.3",
                                    "versionEndExcluding": "6.13"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/c55a4c5a04bae40dcdc1e1c19d8eb79a06fb3397"
                },
                {
                    "url": "https://git.kernel.org/stable/c/2b0f2fc9ed62e73c95df1fa8ed2ba3dac54699df"
                }
            ],
            "title": "Bluetooth: hci_conn: Use disable_delayed_work_sync",
            "x_generator": {
                "engine": "bippy-1.2.0"
            }
        }
    }
}