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CVE-2024-56591 (GCVE-0-2024-56591)

Vulnerability from cvelistv5 – Published: 2024-12-27 14:50 – Updated: 2026-08-05 11:45
VLAI
Title
Bluetooth: hci_conn: Use disable_delayed_work_sync
Summary
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_conn: Use disable_delayed_work_sync This makes use of disable_delayed_work_sync instead cancel_delayed_work_sync as it not only cancel the ongoing work but also disables new submit which is disarable since the object holding the work is about to be freed.
Severity
8.8 (High)
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 19c40e3bcaf2d969f5d4ee85bbe1330b54d36d9c , < c55a4c5a04bae40dcdc1e1c19d8eb79a06fb3397 (git)
Affected: 19c40e3bcaf2d969f5d4ee85bbe1330b54d36d9c , < 2b0f2fc9ed62e73c95df1fa8ed2ba3dac54699df (git)
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Linux Linux Affected: 3.3
Unaffected: 0 , < 3.3 (semver)
Unaffected: 6.12.5 , ≤ 6.12.* (semver)
Unaffected: 6.13 , ≤ * (original_commit_for_fix)
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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/bluetooth/hci_conn.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
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              "status": "affected",
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              "versionType": "git"
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              "status": "affected",
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              "versionType": "git"
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              "version": "0",
              "versionType": "semver"
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              "status": "unaffected",
              "version": "6.12.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.13",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
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          "nodes": [
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                  "vulnerable": true
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              "negate": false,
              "operator": "OR"
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            "baseSeverity": "HIGH",
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              "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 \u2014 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\u0027s 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\u0027s 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\u0027s `-\u003efunction` and the work\u0027s `-\u003efunc` are later dereferenced out of it, so heap spraying yields a controlled write and an indirect call \u2014 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."
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    "cveId": "CVE-2024-56591",
    "datePublished": "2024-12-27T14:50:58.674Z",
    "dateReserved": "2024-12-27T14:03:06.003Z",
    "dateUpdated": "2026-08-05T11:45:13.959Z",
    "state": "PUBLISHED"
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      "version": "18"
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      "id": "CVE-2024-56591",
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      "title": "SUSE CVE CVE-2024-56591",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2024-56591.json",
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  }
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.