CVE-2026-53256 (GCVE-0-2026-53256)
Vulnerability from cvelistv5
Published
2026-06-25 08:39
Modified
2026-08-05 12:34
Severity ?
8.0 (High) - CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: RFCOMM: hold listener socket in rfcomm_connect_ind() rfcomm_get_sock_by_channel() scans rfcomm_sk_list under the list lock, but returns the selected listener after dropping that lock without taking a reference. rfcomm_connect_ind() then locks the listener, queues a child socket on it, and may notify it after unlocking it. The buggy scenario involves two paths, with each column showing the order within that path: rfcomm_connect_ind(): listener close: 1. Find parent in 1. close() enters rfcomm_get_sock_by_channel() rfcomm_sock_release(). 2. Drop rfcomm_sk_list.lock 2. rfcomm_sock_shutdown() without pinning parent. closes the listener. 3. Call lock_sock(parent) and 3. rfcomm_sock_kill() bt_accept_enqueue(parent, unlinks and puts parent. sk, true). 4. Read parent flags and may 4. parent can be freed. call sk_state_change(). If close wins the race, parent can be freed before rfcomm_connect_ind() reaches lock_sock(), bt_accept_enqueue(), or the deferred-setup callback. Take a reference on the listener before leaving rfcomm_sk_list.lock. After lock_sock() succeeds, recheck that it is still in BT_LISTEN before queueing a child, cache the deferred-setup bit while the parent is locked, and drop the reference after the last parent use. KASAN reported a slab-use-after-free in lock_sock_nested() from rfcomm_connect_ind(), with the freeing stack going through rfcomm_sock_kill() and rfcomm_sock_release().
References
Impacted products
Vendor Product Version
Linux Linux Version: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2
Version: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2
Version: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2
Version: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2
Version: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2
Version: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2
Version: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2
Version: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2
 Create a notification for this product.
Show details on NVD website

To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/bluetooth/rfcomm/sock.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "f5ec76bdbeb80f75ad0be204371afffee0f8fac8",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "a07d741c077d4e34b16458241a94d29039386553",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "1f73f92f66251065a5f39b09a47cf05ea14d3107",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "de31973ef00e5aa55496f84cf6a44bb157a34e02",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "b0e33e409715c617e2a20f46f99aa5403a14dfda",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "8802413ce63175fb522a2bd609fb043a3550c720",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "6f4462d12133106460d7c046b95aad2491e3fddf",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "43c441edacf953b39517a44f5e5e10a93618b226",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/bluetooth/rfcomm/sock.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "2.6.12"
            },
            {
              "lessThan": "2.6.12",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.259",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.210",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.176",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.143",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.94",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.36",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.0.*",
              "status": "unaffected",
              "version": "7.0.13",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.1",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.10.259",
                  "versionStartIncluding": "2.6.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.15.210",
                  "versionStartIncluding": "2.6.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.176",
                  "versionStartIncluding": "2.6.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.143",
                  "versionStartIncluding": "2.6.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.94",
                  "versionStartIncluding": "2.6.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.36",
                  "versionStartIncluding": "2.6.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.0.13",
                  "versionStartIncluding": "2.6.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1",
                  "versionStartIncluding": "2.6.12",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: RFCOMM: hold listener socket in rfcomm_connect_ind()\n\nrfcomm_get_sock_by_channel() scans rfcomm_sk_list under the list lock,\nbut returns the selected listener after dropping that lock without\ntaking a reference. rfcomm_connect_ind() then locks the listener,\nqueues a child socket on it, and may notify it after unlocking it.\n\nThe buggy scenario involves two paths, with each column showing the\norder within that path:\n\nrfcomm_connect_ind():            listener close:\n  1. Find parent in              1. close() enters\n     rfcomm_get_sock_by_channel()   rfcomm_sock_release().\n  2. Drop rfcomm_sk_list.lock    2. rfcomm_sock_shutdown()\n     without pinning parent.        closes the listener.\n  3. Call lock_sock(parent) and  3. rfcomm_sock_kill()\n     bt_accept_enqueue(parent,      unlinks and puts parent.\n     sk, true).\n  4. Read parent flags and may   4. parent can be freed.\n     call sk_state_change().\n\nIf close wins the race, parent can be freed before\nrfcomm_connect_ind() reaches lock_sock(), bt_accept_enqueue(), or the\ndeferred-setup callback.\n\nTake a reference on the listener before leaving rfcomm_sk_list.lock.\nAfter lock_sock() succeeds, recheck that it is still in BT_LISTEN\nbefore queueing a child, cache the deferred-setup bit while the parent\nis locked, and drop the reference after the last parent use.\n\nKASAN reported a slab-use-after-free in lock_sock_nested() from\nrfcomm_connect_ind(), with the freeing stack going through\nrfcomm_sock_kill() and rfcomm_sock_release()."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:A - The vulnerable path is reached by Bluetooth RFCOMM/L2CAP traffic from a nearby peer, so the attacker must be within Bluetooth radio range rather than merely local or internet-routable.\nAC:L - The race is between an inbound RFCOMM connect indication and listener close; an attacker with an unprivileged local RFCOMM listener plus a controlled adjacent Bluetooth peer can drive both sides repeatedly.\nPR:L - Creating, binding, listening on, and closing an RFCOMM stream socket has no CAP_NET_ADMIN gate, so only low local privileges are needed to control the listener side of the race.\nUI:N - No victim user action is required once the vulnerable listener/race setup exists; the attacker drives the RFCOMM connection attempts and close timing.\nS:U - The corruption is within the kernel networking/Bluetooth socket lifetime domain and does not cross a separate security authority such as a VM or IOMMU boundary.\nC:H - This is a slab use-after-free of a kernel struct sock, and the stale pointer is reused for locking, queueing, state checks, and callback-related state, making high confidentiality impact defensible.\nI:H - The stale listener socket can be operated on after free, including accept-queue manipulation and potential callback use, so kernel memory corruption/control-flow exploitation is defensible.\nA:H - KASAN reported a slab-use-after-free in this path, and even non-exploited triggering can crash or oops the kernel."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T12:34:36.875Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/f5ec76bdbeb80f75ad0be204371afffee0f8fac8"
        },
        {
          "url": "https://git.kernel.org/stable/c/a07d741c077d4e34b16458241a94d29039386553"
        },
        {
          "url": "https://git.kernel.org/stable/c/1f73f92f66251065a5f39b09a47cf05ea14d3107"
        },
        {
          "url": "https://git.kernel.org/stable/c/de31973ef00e5aa55496f84cf6a44bb157a34e02"
        },
        {
          "url": "https://git.kernel.org/stable/c/b0e33e409715c617e2a20f46f99aa5403a14dfda"
        },
        {
          "url": "https://git.kernel.org/stable/c/8802413ce63175fb522a2bd609fb043a3550c720"
        },
        {
          "url": "https://git.kernel.org/stable/c/6f4462d12133106460d7c046b95aad2491e3fddf"
        },
        {
          "url": "https://git.kernel.org/stable/c/43c441edacf953b39517a44f5e5e10a93618b226"
        }
      ],
      "title": "Bluetooth: RFCOMM: hold listener socket in rfcomm_connect_ind()",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-53256",
    "datePublished": "2026-06-25T08:39:46.591Z",
    "dateReserved": "2026-06-09T07:44:35.394Z",
    "dateUpdated": "2026-08-05T12:34:36.875Z",
    "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.