FKIE_CVE-2026-68381

Vulnerability from fkie_nvd - Published: 2026-08-10 13:20 - Updated: 2026-08-17 06:17
Severity
9.8 (Critical) - CVSS:3.1/AV:N/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: ksmbd: pin conn during async oplock break notification smb2_oplock_break_noti() and smb2_lease_break_noti() store a ksmbd_conn pointer in an async ksmbd_work and then queue that work on ksmbd-io. The work only increments conn->r_count, which prevents teardown from passing the pending-request wait after the increment, but it does not pin the struct ksmbd_conn object. If connection teardown races with an oplock break notification, the last conn reference can be dropped before the queued worker finishes. The worker then uses the freed conn in ksmbd_conn_write() and ksmbd_conn_r_count_dec(). Take a real conn reference when publishing the conn pointer to the async work item, and drop it after the notification work has decremented r_count. Apply the same lifetime rule to lease break notification, which uses the same work->conn pattern.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/0f72fc9659d7f585460d43c158055df5afdcffb6
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/14062c74e5b25c27edcff7a2fe0dc701c930b372
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/6ecb252efa0b413ac3d9979fb4eec247f8fc1258
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/793e1c7041b93af96ff87e678329bc16aee7ba88
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/aa5d8f3f96aa11a4a54ce993c11ce8af11c546f9
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/smb/server/oplock.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "0f72fc9659d7f585460d43c158055df5afdcffb6",
              "status": "affected",
              "version": "09aeab68033161cb54f194da93e51a11aee6144b",
              "versionType": "git"
            },
            {
              "lessThan": "793e1c7041b93af96ff87e678329bc16aee7ba88",
              "status": "affected",
              "version": "a4261bbc33fbf99b99c80aa3a2c5097611802980",
              "versionType": "git"
            },
            {
              "lessThan": "6ecb252efa0b413ac3d9979fb4eec247f8fc1258",
              "status": "affected",
              "version": "3aa660c059240e0c795217182cf7df32909dd917",
              "versionType": "git"
            },
            {
              "lessThan": "14062c74e5b25c27edcff7a2fe0dc701c930b372",
              "status": "affected",
              "version": "3aa660c059240e0c795217182cf7df32909dd917",
              "versionType": "git"
            },
            {
              "lessThan": "aa5d8f3f96aa11a4a54ce993c11ce8af11c546f9",
              "status": "affected",
              "version": "3aa660c059240e0c795217182cf7df32909dd917",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "f17d1c63a76b0fe8e9c78023a86507a3a6d62cfa",
              "versionType": "git"
            },
            {
              "lessThan": "6.6.148",
              "status": "affected",
              "version": "6.6.84",
              "versionType": "semver"
            },
            {
              "lessThan": "6.12.101",
              "status": "affected",
              "version": "6.12.20",
              "versionType": "semver"
            },
            {
              "lessThan": "6.14",
              "status": "affected",
              "version": "6.13.8",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/smb/server/oplock.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.14"
            },
            {
              "lessThan": "6.14",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.148",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.101",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.42",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.6",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: pin conn during async oplock break notification\n\nsmb2_oplock_break_noti() and smb2_lease_break_noti() store a ksmbd_conn\npointer in an async ksmbd_work and then queue that work on ksmbd-io.  The\nwork only increments conn-\u003er_count, which prevents teardown from passing\nthe pending-request wait after the increment, but it does not pin the\nstruct ksmbd_conn object.\n\nIf connection teardown races with an oplock break notification, the last\nconn reference can be dropped before the queued worker finishes.  The\nworker then uses the freed conn in ksmbd_conn_write() and\nksmbd_conn_r_count_dec().\n\nTake a real conn reference when publishing the conn pointer to the async\nwork item, and drop it after the notification work has decremented\nr_count.  Apply the same lifetime rule to lease break notification, which\nuses the same work-\u003econn pattern."
    }
  ],
  "id": "CVE-2026-68381",
  "lastModified": "2026-08-17T06:17:46.560",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 9.8,
          "baseSeverity": "CRITICAL",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 5.9,
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-08-10T13:20:31.197",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/0f72fc9659d7f585460d43c158055df5afdcffb6"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/14062c74e5b25c27edcff7a2fe0dc701c930b372"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/6ecb252efa0b413ac3d9979fb4eec247f8fc1258"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/793e1c7041b93af96ff87e678329bc16aee7ba88"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/aa5d8f3f96aa11a4a54ce993c11ce8af11c546f9"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}



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