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CVE-2023-54214 (GCVE-0-2023-54214)

Vulnerability from cvelistv5 – Published: 2025-12-30 12:11 – Updated: 2026-08-05 09:18
VLAI
Title
Bluetooth: L2CAP: Fix potential user-after-free
Summary
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: Fix potential user-after-free This fixes all instances of which requires to allocate a buffer calling alloc_skb which may release the chan lock and reacquire later which makes it possible that the chan is disconnected in the meantime.
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: a6a5568c03c4805d4d250f6bd9d468eeeb4ea059 , < b2fde8cb2a25125111f2144604e0e7c0ebcc4bba (git)
Affected: a6a5568c03c4805d4d250f6bd9d468eeeb4ea059 , < a6a7d1541fefddf7ca0cfb34c1bff63ff809cc49 (git)
Affected: a6a5568c03c4805d4d250f6bd9d468eeeb4ea059 , < 60aaccf16d1e099c16bebfb96428ae762cb528f7 (git)
Affected: a6a5568c03c4805d4d250f6bd9d468eeeb4ea059 , < b8ed41cc04fb74005aa51d17865ca3d022760335 (git)
Affected: a6a5568c03c4805d4d250f6bd9d468eeeb4ea059 , < 31a288a4df7f6a28e65da22a4ab2add4a963738e (git)
Affected: a6a5568c03c4805d4d250f6bd9d468eeeb4ea059 , < 64e28ecf44e46de9f01915a4146706a21c3469d2 (git)
Affected: a6a5568c03c4805d4d250f6bd9d468eeeb4ea059 , < 994e3e18908f5c4a12d07b44018e6aa85f071048 (git)
Affected: a6a5568c03c4805d4d250f6bd9d468eeeb4ea059 , < df5703348813235874d851934e957c3723d71644 (git)
guessed Create a notification for this product.
Linux Linux Affected: 3.5
Unaffected: 0 , < 3.5 (semver)
Unaffected: 4.14.308 , ≤ 4.14.* (semver)
Unaffected: 4.19.276 , ≤ 4.19.* (semver)
Unaffected: 5.4.235 , ≤ 5.4.* (semver)
Unaffected: 5.10.173 , ≤ 5.10.* (semver)
Unaffected: 5.15.99 , ≤ 5.15.* (semver)
Unaffected: 6.1.16 , ≤ 6.1.* (semver)
Unaffected: 6.2.3 , ≤ 6.2.* (semver)
Unaffected: 6.3 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
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{
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          "product": "Linux",
          "programFiles": [
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              "status": "unaffected",
              "version": "6.3",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
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          "nodes": [
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                  "versionStartIncluding": "3.5",
                  "vulnerable": true
                },
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                  "versionEndExcluding": "6.3",
                  "versionStartIncluding": "3.5",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: L2CAP: Fix potential user-after-free\n\nThis fixes all instances of which requires to allocate a buffer calling\nalloc_skb which may release the chan lock and reacquire later which\nmakes it possible that the chan is disconnected in the meantime."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 8.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:A - The vulnerable window is opened and closed by a remote Bluetooth peer over an L2CAP/RFCOMM/LE CoC connection, which requires only radio proximity to the target. Per kernel scoring convention Bluetooth-reachable bugs are Adjacent.\nAC:L - The attacker controls both sides of the race: withholding L2CAP credits (or ACL buffers) parks the sender in the blocking `bt_skb_send_alloc()` with the chan lock released for an unbounded time, and the attacker then terminates the link to run `l2cap_conn_del()`/`kfree(conn)` inside that window. This makes the race deterministic rather than dependent on timing luck.\nPR:N - No local account and no privileges are needed \u2014 the sending side is the kernel\u0027s own RFCOMM session or a system Bluetooth daemon, and L2CAP/LE CoC channels at BT_SECURITY_LOW accept connections without pairing or authentication. The attacker is purely an unauthenticated adjacent device.\nUI:N - Exploitation needs only a connectable/discoverable target or an already-established profile connection; the freed-conn dereference happens entirely within normal send and link-teardown handling. No victim action is required.\nS:U - The corruption and its consequences are confined to the kernel\u0027s own security authority, with no crossing of a VM, IOMMU, or sandbox boundary. This is a standard in-kernel memory-safety issue.\nC:H - This is a use-after-free read of a freed `struct l2cap_conn` slab object whose contents the attacker can influence by reclaiming the slot with heap spray, and the value read (`conn-\u003emtu`) feeds fragment sizing and copy loops. UAF of an attacker-groomable object is treated as enabling arbitrary read.\nI:H - The dangling `l2cap_conn` is used to drive skb allocation and fragmentation while the freed slab is attacker-reclaimable, giving heap-grooming leverage over subsequent kernel allocations and control-flow-relevant state. Per kernel guidance a use-after-free is scored as exploitable for arbitrary write/control-flow hijack.\nA:H - The freed-object read reliably oopses under any hardening (KASAN/slab poisoning) and, when the reclaimed `conn-\u003emtu` reads as 0, `count` becomes 0 so `len` never decreases \u2014 an infinite skb-allocation loop causing hang and memory exhaustion. Either outcome is a full denial of service."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T09:18:06.231Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/b2fde8cb2a25125111f2144604e0e7c0ebcc4bba"
        },
        {
          "url": "https://git.kernel.org/stable/c/a6a7d1541fefddf7ca0cfb34c1bff63ff809cc49"
        },
        {
          "url": "https://git.kernel.org/stable/c/60aaccf16d1e099c16bebfb96428ae762cb528f7"
        },
        {
          "url": "https://git.kernel.org/stable/c/b8ed41cc04fb74005aa51d17865ca3d022760335"
        },
        {
          "url": "https://git.kernel.org/stable/c/31a288a4df7f6a28e65da22a4ab2add4a963738e"
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        },
        {
          "url": "https://git.kernel.org/stable/c/df5703348813235874d851934e957c3723d71644"
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      ],
      "title": "Bluetooth: L2CAP: Fix potential user-after-free",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
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    "assignerShortName": "Linux",
    "cveId": "CVE-2023-54214",
    "datePublished": "2025-12-30T12:11:11.383Z",
    "dateReserved": "2025-12-30T12:06:44.500Z",
    "dateUpdated": "2026-08-05T09:18:06.231Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
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      "cve": "CVE-2023-54214",
      "date": "2026-09-16",
      "epss": "0.00293",
      "percentile": "0.21972"
    },
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meantime.\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"net/bluetooth/l2cap_core.c\",\"net/bluetooth/l2cap_sock.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"a6a5568c03c4805d4d250f6bd9d468eeeb4ea059\",\"lessThan\":\"b2fde8cb2a25125111f2144604e0e7c0ebcc4bba\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"a6a5568c03c4805d4d250f6bd9d468eeeb4ea059\",\"lessThan\":\"a6a7d1541fefddf7ca0cfb34c1bff63ff809cc49\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"a6a5568c03c4805d4d250f6bd9d468eeeb4ea059\",\"lessThan\":\"60aaccf16d1e099c16bebfb96428ae762cb528f7\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"a6a5568c03c4805d4d250f6bd9d468eeeb4ea059\",\"lessThan\":\"b8ed41cc04fb74005aa51d17865ca3d022760335\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"a6a5568c03c4805d4d250f6bd9d468eeeb4ea059\",\"lessThan\":\"31a288a4df7f6a28e65da22a4ab2add4a963738e\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"a6a5568c03c4805d4d250f6bd9d468eeeb4ea059\",\"lessThan\":\"64e28ecf44e46de9f01915a4146706a21c3469d2\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"a6a5568c03c4805d4d250f6bd9d468eeeb4ea059\",\"lessThan\":\"994e3e18908f5c4a12d07b44018e6aa85f071048\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"a6a5568c03c4805d4d250f6bd9d468eeeb4ea059\",\"lessThan\":\"df5703348813235874d851934e957c3723d71644\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"net/bluetooth/l2cap_core.c\",\"net/bluetooth/l2cap_sock.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"3.5\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"3.5\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"4.14.308\",\"lessThanOrEqual\":\"4.14.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"4.19.276\",\"lessThanOrEqual\":\"4.19.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.4.235\",\"lessThanOrEqual\":\"5.4.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.10.173\",\"lessThanOrEqual\":\"5.10.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.15.99\",\"lessThanOrEqual\":\"5.15.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.1.16\",\"lessThanOrEqual\":\"6.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.2.3\",\"lessThanOrEqual\":\"6.2.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.3\",\"lessThanOrEqual\":\"*\",\"versionType\":\"original_commit_for_fix\",\"status\":\"unaffected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"type\":\"Secondary\",\"cvssData\":{\"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\",\"attackVector\":\"ADJACENT_NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":2.8,\"impactScore\":5.9}]},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/31a288a4df7f6a28e65da22a4ab2add4a963738e\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/60aaccf16d1e099c16bebfb96428ae762cb528f7\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/64e28ecf44e46de9f01915a4146706a21c3469d2\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/994e3e18908f5c4a12d07b44018e6aa85f071048\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/a6a7d1541fefddf7ca0cfb34c1bff63ff809cc49\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/b2fde8cb2a25125111f2144604e0e7c0ebcc4bba\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/b8ed41cc04fb74005aa51d17865ca3d022760335\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/df5703348813235874d851934e957c3723d71644\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}",
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-08-05T03:45:12+00:00",
      "cve": "CVE-2023-54214",
      "id": "CVE-2023-54214",
      "initial_release_date": "2023-01-01T00:00:00+00:00",
      "product_status:fixed": "279",
      "product_status:known_affected": "98",
      "product_status:known_not_affected": "90",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: Bluetooth: L2CAP: Fix potential user-after-free",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2023/cve-2023-54214.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-09-01T01:15:00Z",
      "cve": "CVE-2023-54214",
      "id": "CVE-2023-54214",
      "initial_release_date": "2025-12-31T00:28:21Z",
      "product_status:known_affected": "548",
      "product_status:known_not_affected": "178",
      "product_status:recommended": "262",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2023-54214",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2023-54214.json",
      "version": "25"
    }
  }
}



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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.

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  • 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.
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  • 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.


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