CVE-2023-54214 (GCVE-0-2023-54214)
Vulnerability from cvelistv5
Published
2025-12-30 12:11
Modified
2026-08-05 09:18
Severity ?
8.8 (High) - CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
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.
References
Impacted products
Vendor Product Version
Linux Linux Version: a6a5568c03c4805d4d250f6bd9d468eeeb4ea059
Version: a6a5568c03c4805d4d250f6bd9d468eeeb4ea059
Version: a6a5568c03c4805d4d250f6bd9d468eeeb4ea059
Version: a6a5568c03c4805d4d250f6bd9d468eeeb4ea059
Version: a6a5568c03c4805d4d250f6bd9d468eeeb4ea059
Version: a6a5568c03c4805d4d250f6bd9d468eeeb4ea059
Version: a6a5568c03c4805d4d250f6bd9d468eeeb4ea059
Version: a6a5568c03c4805d4d250f6bd9d468eeeb4ea059
 Create a notification for this product.
Show details on NVD website

To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/bluetooth/l2cap_core.c",
            "net/bluetooth/l2cap_sock.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "b2fde8cb2a25125111f2144604e0e7c0ebcc4bba",
              "status": "affected",
              "version": "a6a5568c03c4805d4d250f6bd9d468eeeb4ea059",
              "versionType": "git"
            },
            {
              "lessThan": "a6a7d1541fefddf7ca0cfb34c1bff63ff809cc49",
              "status": "affected",
              "version": "a6a5568c03c4805d4d250f6bd9d468eeeb4ea059",
              "versionType": "git"
            },
            {
              "lessThan": "60aaccf16d1e099c16bebfb96428ae762cb528f7",
              "status": "affected",
              "version": "a6a5568c03c4805d4d250f6bd9d468eeeb4ea059",
              "versionType": "git"
            },
            {
              "lessThan": "b8ed41cc04fb74005aa51d17865ca3d022760335",
              "status": "affected",
              "version": "a6a5568c03c4805d4d250f6bd9d468eeeb4ea059",
              "versionType": "git"
            },
            {
              "lessThan": "31a288a4df7f6a28e65da22a4ab2add4a963738e",
              "status": "affected",
              "version": "a6a5568c03c4805d4d250f6bd9d468eeeb4ea059",
              "versionType": "git"
            },
            {
              "lessThan": "64e28ecf44e46de9f01915a4146706a21c3469d2",
              "status": "affected",
              "version": "a6a5568c03c4805d4d250f6bd9d468eeeb4ea059",
              "versionType": "git"
            },
            {
              "lessThan": "994e3e18908f5c4a12d07b44018e6aa85f071048",
              "status": "affected",
              "version": "a6a5568c03c4805d4d250f6bd9d468eeeb4ea059",
              "versionType": "git"
            },
            {
              "lessThan": "df5703348813235874d851934e957c3723d71644",
              "status": "affected",
              "version": "a6a5568c03c4805d4d250f6bd9d468eeeb4ea059",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/bluetooth/l2cap_core.c",
            "net/bluetooth/l2cap_sock.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "3.5"
            },
            {
              "lessThan": "3.5",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "4.14.*",
              "status": "unaffected",
              "version": "4.14.308",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "4.19.*",
              "status": "unaffected",
              "version": "4.19.276",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.4.*",
              "status": "unaffected",
              "version": "5.4.235",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.173",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.99",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.16",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.2.*",
              "status": "unaffected",
              "version": "6.2.3",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.3",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "4.14.308",
                  "versionStartIncluding": "3.5",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "4.19.276",
                  "versionStartIncluding": "3.5",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.4.235",
                  "versionStartIncluding": "3.5",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.10.173",
                  "versionStartIncluding": "3.5",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.15.99",
                  "versionStartIncluding": "3.5",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.16",
                  "versionStartIncluding": "3.5",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.2.3",
                  "versionStartIncluding": "3.5",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "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"
        },
        {
          "url": "https://git.kernel.org/stable/c/64e28ecf44e46de9f01915a4146706a21c3469d2"
        },
        {
          "url": "https://git.kernel.org/stable/c/994e3e18908f5c4a12d07b44018e6aa85f071048"
        },
        {
          "url": "https://git.kernel.org/stable/c/df5703348813235874d851934e957c3723d71644"
        }
      ],
      "title": "Bluetooth: L2CAP: Fix potential user-after-free",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "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"
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
  • Confirmed: The vulnerability is confirmed from an analyst perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
  • Patched: This vulnerability was successfully patched by the user reporting the sighting.
  • Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
  • Not confirmed: The user expresses doubt about the veracity of the vulnerability.
  • Not patched: This vulnerability was not successfully patched by the user reporting the sighting.